Documentation

• 1: Kluctl
• 1.1: Kluctl project
• 1.1.1: targets
• 1.2: Deployments
• 1.2.1: Deployments
• 1.2.2: Kustomize Integration
• 1.2.3: Container Images
• 1.2.4: Helm Integration
• 1.2.5: SOPS Integration
• 1.2.6: Hooks
• 1.2.7: Readiness
• 1.2.8: Tags
• 1.2.9: Annotations
• 1.2.9.1: All resources
• 1.2.9.2: Hooks
• 1.2.9.3: Validation
• 1.2.9.4: Kustomize
• 1.3: Templating
• 1.3.1: Predefined Variables
• 1.3.2: Variable Sources
• 1.3.3: Filters
• 1.3.4: Functions
• 1.4: Commands
• 1.4.1: Common Arguments
• 1.4.2: Environment Variables
• 1.4.3: controller install
• 1.4.4: controller run
• 1.4.5: delete
• 1.4.6: deploy
• 1.4.7: diff
• 1.4.8: helm-pull
• 1.4.9: helm-update
• 1.4.10: list-images
• 1.4.11: list-targets
• 1.4.12: poke-images
• 1.4.13: prune
• 1.4.14: render
• 1.4.15: validate
• 1.4.16: webui build
• 1.4.17: webui run
• 1.5: Installation
• 1.6: Get Started
• 2: Kluctl GitOps
• 2.1: Metrics
• 2.1.1: v1beta1 metrics
• 2.1.1.1: Metrics of the KluctlDeployment Controller
• 2.2: Specs
• 2.2.1: v1beta1 specs
• 2.2.1.1: KluctlDeployment
• 2.3: Installation
• 2.4: Legacy Controller Migration
• 2.5: Kluctl Controller API reference
• 3: Kluctl Webui
• 3.1: Installation
• 3.2: Azure AD Integration
• 3.3: Running locally
• 4: Template Controller
• 4.1: Installation
• 4.2: Specs
• 4.2.1: v1alpha1 specs
• 4.2.1.1: ObjectTemplate
• 4.2.1.2: GitProjector
• 4.2.1.3: GithubComment
• 4.2.1.4: GitlabComment
• 4.2.1.5: ListGithubPullRequests
• 4.2.1.6: TextTemplate
• 4.2.1.7: ListGitlabMergeRequests
• 4.3: Security
• 4.4: Templating
• 4.5: Use Case: Dynamic environments for Pull Requests
• 4.6: Use Case: Transformation of Secrets/Objects
• 4.7: Template Controller API reference
• 5: Guides
• 5.1: Tutorials
• 5.1.1: Microservices Demo
• 5.1.1.1: 1. Basic Project Setup
• 5.1.1.2: 2. Helm Integration
• 5.1.1.3: 3. Templating and multi-env deployments
• 5.2: Examples
• 5.2.1: Simple
• 5.2.2: Simple Helm
• 5.2.3: Microservices demo

1 - Kluctl

What is Kluctl?

Kluctl is the missing glue that puts together your (and any third-party) deployments into one large declarative Kubernetes deployment, while making it fully manageable (deploy, diff, prune, delete, …) via one unified command line interface.

Core Concepts

These are some core concepts in Kluctl.

Kluctl project

The kluctl project defines targets. It is defined via the .kluctl.yaml configuration file.

Targets

A target defines a target cluster and a set of deployment arguments. Multiple targets can use the same cluster. Targets allow implementing multi-cluster, multi-environment, multi-customer, … deployments.

Deployments

A deployment defines which Kustomize deployments and which sub-deployments to deploy. It also controls the order of deployments.

Deployments may be configured through deployment arguments, which are typically provided via the targets but might also be provided through the CLI.

Variables

Variables are the main source of configuration. They are either loaded yaml files or directly defined inside deployments. Each variables file that is loaded has access to all the variables which were defined before, allowing complex composition of configuration.

After being loaded, variables are usable through the templating engine at all nearly all places.

Templating

All configuration files (including .kluctl.yaml and deployment.yaml) and all Kubernetes manifests involved are processed through a templating engine. The templating engine allows simple variable substitution and also complex control structures (if/else, for loops, …).

Unified CLI

The CLI of kluctl is designed to be unified/consistent as much as possible. Most commands are centered around targets and thus require you to specify the target name (via -t <target>). If you remember how one command works, it’s easy to figure out how the others work. Output from all targets based commands is also unified, allowing you to easily see what will and what did happen.

History

Kluctl was created after multiple incarnations of complex multi-environment (e.g. dev, test, prod) deployments, including everything from monitoring, persistency and the actual custom services. The philosophy of these deployments was always “what belongs together, should be put together”, meaning that only as much Git repositories were involved as necessary.

The problems to solve turned out to be always the same:

• Dozens of Helm Charts, kustomize deployments and standalone Kubernetes manifests needed to be orchestrated in a way that they work together (services need to connect to the correct databases, and so on)
• (Encrypted) Secrets needed to be managed and orchestrated for multiple environments and clusters
• Updates of components was always risky and required keeping track of what actually changed since the last deployment
• Available tools (Helm, Kustomize) were not suitable to solve this on its own in an easy/natural way
• A lot of bash scripting was required to put things together

When this got more and more complex, and the bash scripts started to become a mess (as “simple” Bash scripts always tend to become), kluctl was started from scratch. It now tries to solve the mentioned problems and provide a useful set of features (commands) in a sane and unified way.

The first versions of kluctl were written in Python, hence the use of Jinja2 templating in kluctl. With version 2.0.0, kluctl was rewritten in Go.

1.1 - Kluctl project

The .kluctl.yaml is the central configuration and entry point for your deployments. It defines which targets are available to invoke commands on.

Example

An example .kluctl.yaml looks like this:

discriminator: "my-project-{{ target.name }}"

targets:
  # test cluster, dev env
  - name: dev
    context: dev.example.com
    args:
      environment: dev
  # test cluster, test env
  - name: test
    context: test.example.com
    args:
      environment: test
  # prod cluster, prod env
  - name: prod
    context: prod.example.com
    args:
      environment: prod

args:
  - name: environment

Allowed fields

discriminator

Specifies a default discriminator template to be used for targets that don’t have their own discriminator specified.

See target discriminator for details.

targets

Please check the targets sub-section for details.

args

A list of arguments that can or must be passed to most kluctl operations. Each of these arguments is then available in templating via the global args object.

An example looks like this:

targets:
...

args:
  - name: environment
  - name: enable_debug
    default: false
  - name: complex_arg
    default:
      my:
        nested1: arg1
        nested2: arg2

These arguments can then be used in templating, e.g. by using {{ args.environment }}.

When calling kluctl, most of the commands will then require you to specify at least -a environment=xxx and optionally -a enable_debug=true

The following sub chapters describe the fields for argument entries.

name

The name of the argument.

default

If specified, the argument becomes optional and will use the given value as default when not specified.

The default value can be an arbitrary yaml value, meaning that it can also be a nested dictionary. In that case, passing args in nested form will only set the nested value. With the above example of complex_arg, running:

kluctl deploy -t my-target -a my.nested1=override`

will only modify the value below my.nested1 and keep the value of my.nested2.

Using Kluctl without .kluctl.yaml

It’s possible to use Kluctl without any .kluctl.yaml. In that case, all commands must be used without specifying the target.

1.1.1 - targets

Specifies a list of targets for which commands can be invoked. A target puts together environment/target specific configuration and the target cluster. Multiple targets can exist which target the same cluster but with differing configuration (via args).

Each value found in the target definition is rendered with a simple Jinja2 context that only contains the target and args. The rendering process is retried 10 times until it finally succeeds, allowing you to reference the target itself in complex ways.

Target entries have the following form:

targets:
...
  - name: <target_name>
    context: <context_name>
    args:
      arg1: <value1>
      arg2: <value2>
      ...
    images:
      - image: my-image
        resultImage: my-image:1.2.3
    discriminator: "my-project-{{ target.name }}"
...

The following fields are allowed per target:

name

This field specifies the name of the target. The name must be unique. It is referred in all commands via the -t option.

context

This field specifies the kubectl context of the target cluster. The context must exist in the currently active kubeconfig. If this field is omitted, Kluctl will always use the currently active context.

args

This fields specifies a map of arguments to be passed to the deployment project when it is rendered. Allowed argument names are configured via deployment args .

images

This field specifies a list of fixed images to be used by images.get_image(...) . The format is identical to the fixed images file .

discriminator

Specifies a discriminator which is used to uniquely identify all deployed objects on the cluster. It is added to all objects as the value of the kluctl.io/discriminator label. This label is then later used to identify all objects belonging to the deployment project and target, so that Kluctl can determine which objects got orphaned and need to be pruned. The discriminator is also used to identify all objects that need to be deleted when kluctl delete is called.

If no discriminator is set for a target, kluctl prune and kluctl delete are not supported.

The discriminator can be a template which is rendered at project loading time. While rendering, only the target and args are available as global variables in the templating context.

The rendered discriminator should be unique on the target cluster to avoid mis-identification of objects from other deployments or targets. It’s good practice to prefix the discriminator with a project name and at least use the target name to make it unique. Example discriminator to achieve this: my-project-name-{{ target.name }}.

If a target is meant to be deployed multiple times, e.g. by using external arguments , the external arguments should be taken into account as well. Example: my-project-name-{{ target.name }}-{{ args.environment_name }}.

A default discriminator can also be specified which is used whenever a target has no discriminator configured.

1.2 - Deployments

A deployment project is collection of deployment items and sub-deployments. Deployment items are usually Kustomize deployments, but can also integrate Helm Charts .

Basic structure

The following visualization shows the basic structure of a deployment project. The entry point of every deployment project is the deployment.yaml file, which then includes further sub-deployments and kustomize deployments. It also provides some additional configuration required for multiple kluctl features to work as expected.

As can be seen, sub-deployments can include other sub-deployments, allowing you to structure the deployment project as you need.

Each level in this structure recursively adds tags to each deployed resources, allowing you to control precisely what is deployed in the future.

Some visualized files/directories have links attached, follow them to get more information.

-- project-dir/
   |-- deployment.yaml
   |-- .gitignore
   |-- kustomize-deployment1/
   |   |-- kustomization.yaml
   |   `-- resource.yaml
   |-- sub-deployment/
   |   |-- deployment.yaml
   |   |-- kustomize-deployment2/
   |   |   |-- resource1.yaml
   |   |   `-- ...
   |   |-- kustomize-deployment3/
   |   |   |-- kustomization.yaml
   |   |   |-- resource1.yaml
   |   |   |-- resource2.yaml
   |   |   |-- patch1.yaml
   |   |   `-- ...
   |   |-- kustomize-with-helm-deployment/
   |   |   |-- charts/
   |   |   |   `-- ...
   |   |   |-- kustomization.yaml
   |   |   |-- helm-chart.yaml
   |   |   `-- helm-values.yaml
   |   `-- subsub-deployment/
   |       |-- deployment.yaml
   |       |-- ... kustomize deployments
   |       `-- ... subsubsub deployments
   `-- sub-deployment/
       `-- ...

Order of deployments

Deployments are done in parallel, meaning that there are usually no order guarantees. The only way to somehow control order, is by placing barriers between kustomize deployments. You should however not overuse barriers, as they negatively impact the speed of kluctl.

Plain Kustomize

It’s also possible to use Kluctl on plain Kustomize deployments. Simply run kluctl deploy from inside the folder of your kustomization.yaml. If you also don’t have a .kluctl.yaml, you can also work without targets.

Please note that pruning and deletion is not supported in this mode.

1.2.1 - Deployments

The deployment.yaml file is the entrypoint for the deployment project. Included sub-deployments also provide a deployment.yaml file with the same structure as the initial one.

An example deployment.yaml looks like this:

deployments:
- path: nginx
- path: my-app
- include: monitoring

commonLabels:
  my.prefix/target: "{{ target.name }}"
  my.prefix/deployment-project: my-deployment-project

The following sub-chapters describe the available fields in the deployment.yaml

deployments

deployments is a list of deployment items. Multiple deployment types are supported, which is documented further down. Individual deployments are performed in parallel, unless a barrier is encountered which causes kluctl to wait for all previous deployments to finish.

Deployments can also be conditional by using the when field.

Simple deployments

Simple deployments are specified via path and are expected to be directories with Kubernetes manifests inside. Kluctl will internally generate a kustomization.yaml from these manifests and treat the deployment item the same way as it would treat a Kustomize deployment .

Example:

deployments:
- path: path/to/manifests

Kustomize deployments

When the deployment item directory specified via path contains a kustomization.yaml, Kluctl will use this file instead of generating one.

Please see Kustomize integration for more details.

Example:

deployments:
- path: path/to/deployment1
- path: path/to/deployment2
  waitReadiness: true

The path must point to a directory relative to the directory containing the deployment.yaml. Only directories that are part of the kluctl project are allowed. The directory must contain a valid kustomization.yaml.

waitReadiness is optional and if set to true instructs kluctl to wait for readiness of each individual object of the kustomize deployment. Readiness is defined in readiness .

Includes

Specifies a sub-deployment project to be included. The included sub-deployment project will inherit many properties of the parent project, e.g. tags, commonLabels and so on.

Example:

deployments:
- include: path/to/sub-deployment

The path must point to a directory relative to the directory containing the deployment.yaml. Only directories that are part of the kluctl project are allowed. The directory must contain a valid deployment.yaml.

Git includes

Specifies an external git project to be included. The project is included the same way with regular includes, except that the included project can not use/load templates from the parent project. An included project might also include further git projects.

Simple example:

deployments:
- git: git@github.com/example/example.git

This will clone the git repository at git@github.com/example/example.git, checkout the default branch and include it into the current project.

Advanced Example:

deployments:
- git:
    url: git@github.com/example/example.git
    ref:
      branch: my-branch
    subDir: some/sub/dir

The url specifies the Git url to be cloned and checked out.

ref is optional and specifies the branch or tag to be used. To specify a branch, set the sub-field branch as seen in the above example. To pass a tag, set the tag field instead. To pass a commit, set the commit field instead.

If ref is omitted, the default branch will be checked out.

subDir is optional and specifies the sub directory inside the git repository to include.

Barriers

Causes kluctl to wait until all previous kustomize deployments have been applied. This is useful when upcoming deployments need the current or previous deployments to be finished beforehand. Previous deployments also include all sub-deployments from included deployments.

Example:

deployments:
- path: kustomizeDeployment1
- path: kustomizeDeployment2
- include: subDeployment1
- barrier: true
# At this point, it's ensured that kustomizeDeployment1, kustomizeDeployment2 and all sub-deployments from
# subDeployment1 are fully deployed.
- path: kustomizeDeployment3

To create a barrier with a custom message, include the message parameter when creating the barrier. The message parameter accepts a string value that represents the custom message.

Example:

deployments:
- path: kustomizeDeployment1
- path: kustomizeDeployment2
- include: subDeployment1
- barrier: true
  message: "Waiting for subDeployment1 to be finished"
# At this point, it's ensured that kustomizeDeployment1, kustomizeDeployment2 and all sub-deployments from
# subDeployment1 are fully deployed.
- path: kustomizeDeployment3

If no custom message is provided, the barrier will be created without a specific message, and the default behavior will be applied.

When viewing the kluctl deploy status, the custom message, if provided, will be displayed along with default barrier information.

deleteObjects

Causes kluctl to delete matching objects, specified by a list of group/kind/name/namespace dictionaries. The order/parallelization of deletion is identical to the order and parallelization of normal deployment items, meaning that it happens in parallel by default until a barrier is encountered.

Example:

deployments:
  - deleteObjects:
      - group: apps
        kind: DaemonSet
        namespace: kube-system
        name: kube-proxy
  - barrier: true
  - path: my-cni

The above example shows how to delete the kube-proxy DaemonSet before installing a CNI (e.g. Cilium in proxy-replacement mode).

deployments common properties

All entries in deployments can have the following common properties:

vars (deployment item)

A list of variable sets to be loaded into the templating context, which is then available in all deployment items and sub-deployments .

See templating for more details.

Example:

deployments:
- path: kustomizeDeployment1
  vars:
    - file: vars1.yaml
    - values:
        var1: value1
- path: kustomizeDeployment2
# all sub-deployments of this include will have the given variables available in their Jinj2 context.
- include: subDeployment1
  vars:
    - file: vars2.yaml

when

Each deployment item can be conditional with the help of the when field. It must be set to a Jinja2 based expression that evaluates to a boolean.

Example:

deployments:
- path: item1
- path: item2
  when: my.var == "my-value"

tags (deployment item)

A list of tags the deployment should have. See tags for more details. For includes, this means that all sub-deployments will get these tags applied to. If not specified, the default tags logic as described in tags is applied.

Example:

deployments:
- path: kustomizeDeployment1
  tags:
    - tag1
    - tag2
- path: kustomizeDeployment2
  tags:
    - tag3
# all sub-deployments of this include will get tag4 applied
- include: subDeployment1
  tags:
    - tag4

alwaysDeploy

Forces a deployment to be included everytime, ignoring inclusion/exclusion sets from the command line. See Deploying with tag inclusion/exclusion for details.

deployments:
- path: kustomizeDeployment1
  alwaysDeploy: true
- path: kustomizeDeployment2

Please note that alwaysDeploy will also cause kluctl render to always render the resources.

skipDeleteIfTags

Forces exclusion of a deployment whenever inclusion/exclusion tags are specified via command line. See Deleting with tag inclusion/exclusion for details.

deployments:
- path: kustomizeDeployment1
  skipDeleteIfTags: true
- path: kustomizeDeployment2

onlyRender

Causes a path to be rendered only but not treated as a deployment item. This can be useful if you for example want to use Kustomize components which you’d refer from other deployment items.

deployments:
- path: component
  onlyRender: true
- path: kustomizeDeployment2

vars (deployment project)

A list of variable sets to be loaded into the templating context, which is then available in all deployment items and sub-deployments .

See templating for more details.

commonLabels

A dictionary of labels and values to be added to all resources deployed by any of the deployment items in this deployment project.

Consider the following example deployment.yaml:

deployments:
  - path: nginx
  - include: sub-deployment1

commonLabels:
  my.prefix/target: {{ target.name }}
  my.prefix/deployment-name: my-deployment-project-name
  my.prefix/label-1: value-1
  my.prefix/label-2: value-2

Every resource deployed by the kustomize deployment nginx will now get the four provided labels attached. All included sub-deployment projects (e.g. sub-deployment1) will also recursively inherit these labels and pass them further down.

In case an included sub-deployment project also contains commonLabels, both dictionaries of commonLabels are merged inside the included sub-deployment project. In case of conflicts, the included common labels override the inherited.

Please note that these commonLabels are not related to commonLabels supported in kustomization.yaml files. It was decided to not rely on this feature but instead attach labels manually to resources right before sending them to kubernetes. This is due to an implementation detail in kustomize which causes commonLabels to also be applied to label selectors, which makes otherwise editable resources read-only when it comes to commonLabels.

commonAnnotations

A dictionary of annotations and values to be added to all resources deployed by any of the deployment items in this deployment project.

commonAnnotations are handled the same as commonLabels in regard to inheriting, merging and overriding.

overrideNamespace

A string that is used as the default namespace for all kustomize deployments which don’t have a namespace set in their kustomization.yaml.

tags (deployment project)

A list of common tags which are applied to all kustomize deployments and sub-deployment includes.

See tags for more details.

ignoreForDiff

A list of objects and fields to ignore while performing diffs. Consider the following example:

deployments:
  - ...

ignoreForDiff:
  - group: apps
    kind: Deployment
    namespace: my-namespace
    name: my-deployment
    fieldPath: spec.replicas

This will remove the spec.replicas field from every resource that matches the object. group, kind, namespace and name can be omitted, which results in all objects matching. fieldPath must be a valid JSON Path . fieldPath may also be a list of JSON paths.

Using regex expressions instead of JSON Pathes is also supported:

deployments:
  - ...

ignoreForDiff:
  - group: apps
    kind: Deployment
    namespace: my-namespace
    name: my-deployment
    fieldPathRegex: metadata.labels.my-label-.*

As an alternative, annotations can be used to control diff behavior of individual resources.

1.2.2 - Kustomize Integration

kluctl uses kustomize to render final resources. This means, that the finest/lowest level in kluctl is represented with kustomize deployments. These kustomize deployments can then perform further customization, e.g. patching and more. You can also use kustomize to easily generate ConfigMaps or secrets from files.

Generally, everything is possible via kustomization.yaml, is thus possible in kluctl.

We advise to read the kustomize reference . You can also look into the official kustomize example .

Using the Kustomize Integration

Please refer to the Kustomize Deployment Item documentation for details.

1.2.3 - Container Images

There are usually 2 different scenarios where Container Images need to be specified:

1. When deploying third party applications like nginx, redis, … (e.g. via the Helm integration ).
   
   • In this case, image versions/tags rarely change, and if they do, this is an explicit change to the deployment. This means it’s fine to have the image versions/tags directly in the deployment manifests.
2. When deploying your own applications.
   
   • In this case, image versions/tags might change very rapidly, sometimes multiple times per hour. Having these versions/tags directly in the deployment manifests can easily lead to commit spam and hard to manage multi-environment deployments.

kluctl offers a better solution for the second case.

images.get_image()

This is solved via a templating function that is available in all templates/resources. The function is part of the global images object and expects the following arguments:

images.get_image(image)

• image
  • The image name/repository. It is looked up the list of fixed images.

The function will lookup the given image in the list of fixed images and return the last match.

Example deployment:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-deployment
spec:
  template:
    spec:
      containers:
      - name: c1
        image: "{{ images.get_image('registry.gitlab.com/my-group/my-project') }}"

Fixed images

Fixed images can be configured multiple methods:

1. Command line argument --fixed-image
2. Command line argument --fixed-images-file
3. Target definition
4. Global ‘images’ variable

Command line argument --fixed-image

You can pass fixed images configuration via the --fixed-image argument . Due to environment variables support in the CLI, you can also use the environment variable KLUCTL_FIXED_IMAGE_XXX to configure fixed images.

The format of the --fixed-image argument is --fixed-image image<:namespace:deployment:container>=result. The simplest example is --fixed-image registry.gitlab.com/my-group/my-project=registry.gitlab.com/my-group/my-project:1.1.2.

Command line argument --fixed-images-file

You can also configure fixed images via a yaml file by using --fixed-images-file /path/to/fixed-images.yaml. file:

images:
  - image: registry.gitlab.com/my-group/my-project
    resultImage: registry.gitlab.com/my-group/my-project:1.1.2

The file must contain a single root list named images with each entry having the following form:

images:
  - image: <image_name>
    resultImage: <result_image>
    # optional fields
    namespace: <namespace>
    deployment: <kind>/<name>
    container: <name>

image (or imageRegex) and resultImage are required. All the other fields are optional and allow to specify in detail for which object the fixed is specified.

You can also specify a regex for the image name:

images:
  - imageRegex: registry\.gitlab\.com/my-group/.*
    resultImage: <result_image>
    # optional fields
    namespace: <namespace>
    deployment: <kind>/<name>
    container: <name>

Target definition

The target definition can optionally specify an images field that can contain the same fixed images configuration as found in the --fixed-images-file file.

Global ‘images’ variable

You can also define a global variable named images via one of the variable sources . This variable must be a list of the same format as the images list in the --fixed-images-file file.

This option allows to externalize fixed images configuration, meaning that you can maintain image versions outside the deployment project, e.g. in another Git repository .

1.2.4 - Helm Integration

kluctl offers a simple-to-use Helm integration, which allows you to reuse many common third-party Helm Charts.

The integration is split into 2 parts/steps/layers. The first is the management and pulling of the Helm Charts, while the second part handles configuration/customization and deployment of the chart.

It is recommended to pre-pull Helm Charts with kluctl helm-pull , which will store the pulled charts inside .helm-charts of the project directory. It is however also possible (but not recommended) to skip the pre-pulling phase and let kluctl pull Charts on-demand.

When pre-pulling Helm Charts, you can also add the resulting Chart contents into version control. This is actually recommended as it ensures that the deployment will always behave the same. It also allows pull-request based reviews on third-party Helm Charts.

How it works

Helm charts are not directly installed via Helm. Instead, kluctl renders the Helm Chart into a single file and then hands over the rendered yaml to kustomize . Rendering is done in combination with a provided helm-values.yaml, which contains the necessary values to configure the Helm Chart.

The resulting rendered yaml is then referred by your kustomization.yaml, from which point on the kustomize integration takes over. This means, that you can perform all desired customization (patches, namespace override, …) as if you provided your own resources via yaml files.

Helm hooks

Helm Hooks are implemented by mapping them to kluctl hooks , based on the following mapping table:

Please note that this is a best effort approach and not 100% compatible to how Helm would run hooks.

helm-chart.yaml

The helm-chart.yaml defines where to get the chart from, which version should be pulled, the rendered output file name, and a few more Helm options. After this file is added to your project, you need to invoke the helm-pull command to pull the Helm Chart into your local project. It is advised to put the pulled Helm Chart into version control, so that deployments will always be based on the exact same Chart (Helm does not guarantee this when pulling).

Example helm-chart.yaml:

helmChart:
  repo: https://charts.bitnami.com/bitnami
  chartName: redis
  chartVersion: 12.1.1
  updateConstraints: ~12.1.0
  skipUpdate: false
  skipPrePull: false
  releaseName: redis-cache
  namespace: "{{ my.jinja2.var }}"
  output: helm-rendered.yaml # this is optional

When running the helm-pull command, it will search for all helm-chart.yaml files in your project and then pull the chart from the specified repository with the specified version. The pull chart will then be located in the sub-directory charts below the same directory as the helm-chart.yaml

The same filename that was specified in output must then be referred in a kustomization.yaml as a normal local resource. If output is omitted, the default value helm-rendered.yaml is used and must also be referenced in kustomization.yaml.

helmChart inside helm-chart.yaml supports the following fields:

repo

The url to the Helm repository where the Helm Chart is located. You can use hub.helm.sh to search for repositories and charts and then use the repos found there.

OCI based repositories are also supported, for example:

helmChart:
  repo: oci://r.myreg.io/mycharts/pepper
  chartName: pepper
  chartVersion: 1.2.3
  releaseName: pepper
  namespace: pepper

path

As alternative to repo, you can also specify path. The path must point to a local Helm Chart that is relative to the helm-chart.yaml. The local Chart must reside in your Kluctl project.

When path is specified, repo, chartName, chartVersion and updateContrainsts are not allowed.

chartName

The name of the chart that can be found in the repository.

chartVersion

The version of the chart. Must be a valid semantic version.

updateConstraints

Specifies version constraints to be used when running helm-update . See Checking Version Constraints for details on the supported syntax.

If omitted, Kluctl will filter out pre-releases by default. Use a updateConstraints like ~1.2.3-0 to enable pre-releases.

skipUpdate

If set to true, skip this Helm Chart when the helm-update command is called. If omitted, defaults to false.

skipPrePull

If set to true, skip pre-pulling of this Helm Chart when running helm-pull . This will also enable pulling on-demand when the deployment project is rendered/deployed.

releaseName

The name of the Helm Release.

namespace

The namespace that this Helm Chart is going to be deployed to. Please note that this should match the namespace that you’re actually deploying the kustomize deployment to. This means, that either namespace in kustomization.yaml or overrideNamespace in deployment.yaml should match the namespace given here. The namespace should also be existing already at the point in time when the kustomize deployment is deployed.

output

This is the file name into which the Helm Chart is rendered into. Your kustomization.yaml should include this same file. The file should not be existing in your project, as it is created on-the-fly while deploying.

skipCRDs

If set to true, kluctl will pass --skip-crds to Helm when rendering the deployment. If set to false (which is the default), kluctl will pass --include-crds to Helm.

helm-values.yaml

This file should be present when you need to pass custom Helm Value to Helm while rendering the deployment. Please read the documentation of the used Helm Charts for details on what is supported.

Updates to helm-charts

In case a Helm Chart needs to be updated, you can either do this manually by replacing the chartVersion value in helm-chart.yaml and the calling the helm-pull command or by simply invoking helm-update with --upgrade and/or --commit being set.

Private Chart Repositories

It is also possible to use private chart repositories. There are currently two options to provide Helm Repository credentials to Kluctl.

Use helm repo add --username xxx --password xxx before

Kluctl will try to find known repositories that are managed by the Helm CLI and then try to reuse the credentials of these. The repositories are identified by the URL of the repository, so it doesn’t matter what name you used when you added the repository to Helm. The same method can be used for client certificate based authentication (--key-file in helm repo add).

Use the –username/–password arguments in kluctl helm-pull

See the helm-pull command . You can control repository credentials via --username, --password and --key-file. Each argument must be in the form credentialsId:value, where the credentialsId must match the id specified in the helm-chart.yaml. Example:

helmChart:
  repo: https://raw.githubusercontent.com/example/private-helm-repo/main/
  credentialsId: private-helm-repo
  chartName: my-chart
  chartVersion: 1.2.3
  releaseName: my-chart
  namespace: default

When credentialsId is specified, Kluctl will require you to specify --username=private-helm-repo:my-username and --password=private-helm-repo:my-password. You can also specify a client-side certificate instead via --key-file=private-helm-repo:/path/to/cert.

Multiple Helm Charts can use the same credentialsId.

Environment variables can also be used instead of arguments. See Environment Variables for details.

Templating

Both helm-chart.yaml and helm-values.yaml are rendered by the templating engine before they are actually used. This means, that you can use all available Jinja2 variables at that point, which can for example be seen in the above helm-chart.yaml example for the namespace.

There is however one exception that leads to a small limitation. When helm-pull reads the helm-chart.yaml, it does NOT render the file via the templating engine. This is because it can not know how to properly render the template as it does have no information about targets (there are no -t arguments set) at that point.

This exception leads to the limitation that the helm-chart.yaml MUST be valid yaml even in case it is not rendered via the templating engine. This makes using control statements (if/for/…) impossible in this file. It also makes it a requirement to use quotes around values that contain templates (e.g. the namespace in the above example).

helm-values.yaml is not subject to these limitations as it is only interpreted while deploying.

1.2.5 - SOPS Integration

Kluctl integrates natively with SOPS . Kluctl is able to decrypt all resources referenced by Kustomize deployment items (including simple deployments ). In addition, Kluctl will also decrypt all variable sources of the types file and git .

Kluctl assumes that you have setup sops as usual so that it knows how to decrypt these files.

Only encrypting Secrets’s data

To only encrypt the data and stringData fields of Kubernetes secrets, use a .sops.yaml configuration file that encrypted_regex to filter encrypted fields:

creation_rules:
  - path_regex: .*.yaml
    encrypted_regex: ^(data|stringData)$

Combining templating and SOPS

As an alternative, you can split secret values and the resulting Kubernetes resources into two different places and then use templating to use the secret values wherever needed. Example:

Write the following content into secrets/my-secrets.yaml:

secrets:
  mySecret: secret-value

And encrypt it with SOPS:

$ sops -e -i secrets/my-secrets.yaml

Add this variables source to one of your deployments :

vars:
  - file: secrets/my-secrets.yaml

deployments:
- ...

Then, in one of your deployment items define the following Secret:

apiVersion: v1
kind: Secret
metadata:
  name: my-secret
  namespace: default
stringData:
  secret: "{{ secrets.mySecret }}"

1.2.6 - Hooks

Kluctl supports hooks in a similar fashion as known from Helm Charts. Hooks are executed/deployed before and/or after the actual deployment of a kustomize deployment.

To mark a resource as a hook, add the kluctl.io/hook annotation to a resource. The value of the annotation must be a comma separated list of hook names. Possible value are described in the next chapter.

Hook types

A deployment is considered to be an “initial” deployment if none of the resources related to the current kustomize deployment are found on the cluster at the time of deployment.

If you need to execute hooks for every deployment, independent of its “initial” state, use pre-deploy-initial,pre-deploy to indicate that it should be executed all the time.

Hook deletion

Hook resources are by default deleted right before creation (if they already existed before). This behavior can be changed by setting the kluctl.io/hook-delete-policy to a comma separated list of the following values:

Hook readiness

After each deployment/execution of the hooks that belong to a deployment stage (before/after deployment), kluctl waits for the hook resources to become “ready”. Readiness is defined here .

It is possible to disable waiting for hook readiness by setting the annotation kluctl.io/hook-wait to “false”.

1.2.7 - Readiness

There are multiple places where kluctl can wait for “readiness” of resources, e.g. for hooks or when waitReadiness is specified on a deployment item. Readiness depends on the resource kind, e.g. for a Job, kluctl would wait until it finishes successfully.

1.2.8 - Tags

Every kustomize deployment has a set of tags assigned to it. These tags are defined in multiple places, which is documented in deployment.yaml . Look for the tags field, which is available in multiple places per deployment project.

Tags are useful when only one or more specific kustomize deployments need to be deployed or deleted.

Default tags

deployment items in deployment projects can have an optional list of tags assigned.

If this list is completely omitted, one single entry is added by default. This single entry equals to the last element of the path in the deployments entry.

Consider the following example:

deployments:
  - path: nginx
  - path: some/subdir

In this example, two kustomize deployments are defined. The first would get the tag nginx while the second would get the tag subdir.

In most cases this heuristic is enough to get proper tags with which you can work. It might however lead to strange or even conflicting tags (e.g. subdir is really a bad tag), in which case you’d have to explicitly set tags.

Tag inheritance

Deployment projects and deployments items inherit the tags of their parents. For example, if a deployment project has a tags property defined, all deployments entries would inherit all these tags. Also, the sub-deployment projects included via deployment items of type include inherit the tags of the deployment project. These included sub-deployments also inherit the tags specified by the deployment item itself.

Consider the following example deployment.yaml:

deployments:
  - include: sub-deployment1
    tags:
      - tag1
      - tag2
  - include: sub-deployment2
    tags:
      - tag3
      - tag4
  - include: subdir/subsub

Any kustomize deployment found in sub-deployment1 would now inherit tag1 and tag2. If sub-deployment1 performs any further includes, these would also inherit these two tags. Inheriting is additive and recursive.

The last sub-deployment project in the example is subject to the same default-tags logic as described in Default tags , meaning that it will get the default tag subsub.

Deploying with tag inclusion/exclusion

Special care needs to be taken when trying to deploy only a specific part of your deployment which requires some base resources to be deployed as well.

Imagine a large deployment is able to deploy 10 applications, but you only want to deploy one of them. When using tags to achieve this, there might be some base resources (e.g. Namespaces) which are needed no matter if everything or just this single application is deployed. In that case, you’d need to set alwaysDeploy to true.

Deleting with tag inclusion/exclusion

Also, in most cases, even more special care has to be taken for the same types of resources as decribed before.

Imagine a kustomize deployment being responsible for namespaces deployments. If you now want to delete everything except deployments that have the persistency tag assigned, the exclusion logic would NOT exclude deletion of the namespace. This would ultimately lead to everything being deleted, and the exclusion tag having no effect.

In such a case, you’d need to set skipDeleteIfTags to true as well.

In most cases, setting alwaysDeploy to true also requires setting skipDeleteIfTags to true.

1.2.9 - Annotations

1.2.9.1 - All resources

The following annotations control the behavior of the deploy and related commands.

Control deploy behavior

The following annotations control deploy behavior, especially in regard to conflict resolution.

kluctl.io/delete

If set to “true”, the resource will be deleted at deployment time. Kluctl will not emit an error in case the resource does not exist. A resource with this annotation does not have to be complete/valid as it is never sent to the Kubernetes api server.

kluctl.io/force-apply

If set to “true”, the whole resource will be force-applied, meaning that all fields will be overwritten in case of field manager conflicts.

kluctl.io/force-apply-field

Specifies a JSON Path for fields that should be force-applied. Matching fields will be overwritten in case of field manager conflicts.

If more than one field needs to be specified, add -xxx to the annotation key, where xxx is an arbitrary number.

kluctl.io/ignore-conflicts

If set to “true”, the whole all fields of the object are going to be ignored when conflicts arise. This effectively disables the warnings that are shown when field ownership is lost.

kluctl.io/ignore-conflicts-field

Specifies a JSON Path for fields that should be ignored when conflicts arise. This effectively disables the warnings that are shown when field ownership is lost.

If more than one field needs to be specified, add -xxx to the annotation key, where xxx is an arbitrary number.

Control deletion/pruning

The following annotations control how delete/prune is behaving.

kluctl.io/skip-delete

If set to “true”, the annotated resource will not be deleted when delete or prune is called.

kluctl.io/skip-delete-if-tags

If set to “true”, the annotated resource will not be deleted when delete or prune is called and inclusion/exclusion tags are used at the same time.

This tag is especially useful and required on resources that would otherwise cause cascaded deletions of resources that do not match the specified inclusion/exclusion tags. Namespaces are the most prominent example of such resources, as they most likely don’t match exclusion tags, but cascaded deletion would still cause deletion of the excluded resources.

Control diff behavior

The following annotations control how diffs are performed.

kluctl.io/diff-name

This annotation will override the name of the object when looking for the in-cluster version of an object used for diffs. This is useful when you are forced to use new names for the same objects whenever the content changes, e.g. for all kinds of immutable resource types.

Example (filename job.yaml):

apiVersion: batch/v1
kind: Job
metadata:
  name: myjob-{{ load_sha256("job.yaml", 6) }}
  annotations:
    kluctl.io/diff-name: myjob
spec:
  template:
    spec:
      containers:
      - name: hello
        image: busybox
        command: ["sh",  "-c", "echo hello"]
      restartPolicy: Never

Without the kluctl.io/diff-name annotation, any change to the job.yaml would be treated as a new object in resulting diffs from various commands. This is due to the inclusion of the file hash in the job name. This would make it very hard to figure out what exactly changed in an object.

With the kluctl.io/diff-name annotation, kluctl will pick an existing job from the cluster with the same diff-name and use it for the diff, making it a lot easier to analyze changes. If multiple objects match, the one with the youngest creationTimestamp is chosen.

Please note that this will not cause old objects (with the same diff-name) to be prunes. You still have to regularely prune the deployment.

kluctl.io/ignore-diff

If set to “true”, the whole resource will be ignored while calculating diffs.

kluctl.io/ignore-diff-field

Specifies a JSON Path for fields that should be ignored while calculating diffs.

If more than one field needs to be specified, add -xxx to the annotation key, where xxx is an arbitrary number.

kluctl.io/ignore-diff-field-regex

Same as kluctl.io/ignore-diff-field but specifying a regular expressions instead of a JSON Path.

If more than one field needs to be specified, add -xxx to the annotation key, where xxx is an arbitrary number.

1.2.9.2 - Hooks

The following annotations control hook execution

See hooks for more details.

kluctl.io/hook

Declares a resource to be a hook, which is deployed/executed as described in hooks . The value of the annotation determines when the hook is deployed/executed.

kluctl.io/hook-weight

Specifies a weight for the hook, used to determine deployment/execution order.

kluctl.io/hook-delete-policy

Defines when to delete the hook resource.

kluctl.io/hook-wait

Defines whether kluctl should wait for hook-completion.

1.2.9.3 - Validation

The following annotations influence the validate command.

validate-result.kluctl.io/xxx

If this annotation is found on a resource that is checked while validation, the key and the value of the annotation are added to the validation result, which is then returned by the validate command.

The annotation key is dynamic, meaning that all annotations that begin with validate-result.kluctl.io/ are taken into account.

kluctl.io/validate-ignore

If this annotation is set to true, the object will be ignored while kluctl validate is run.

1.2.9.4 - Kustomize

Even though the kustomization.yaml from Kustomize deployments are not really Kubernetes resources (as they are not really deployed), they have the same structure as Kubernetes resources. This also means that the kustomization.yaml can define metadata and annotations. Through these annotations, additional behavior on the deployment can be controlled.

Example:

apiVersion: kustomize.config.k8s.io/v1beta1
kind: Kustomization

metadata:
  annotations:
    kluctl.io/barrier: "true"
    kluctl.io/wait-readiness: "true"

resources:
  - deployment.yaml

kluctl.io/barrier

If set to true, kluctl will wait for all previous objects to be applied (but not necessarily ready). This has the same effect as barrier from deployment projects.

kluctl.io/wait-readiness

If set to true, kluctl will wait for readiness of all objects from this kustomization project. Readiness is defined the same as in hook readiness .

1.3 - Templating

kluctl uses a Jinja2 Templating engine to pre-process/render every involved configuration file and resource before actually interpreting it. Only files that are explicitly excluded via .templateignore files are not rendered via Jinja2.

Generally, everything that is possible with Jinja2 is possible in kluctl configuration/resources. Please read into the Jinja2 documentation to understand what exactly is possible and how to use it.

.templateignore

In some cases it is required to exclude specific files from templating, for example when the contents conflict with the used template engine (e.g. Go templates conflict with Jinja2 and cause errors). In such cases, you can place a .templateignore beside the excluded files or into a parent folder of it. The contents/format of the .templateignore file is the same as you would use in a .gitignore file.

Includes and imports

Standard Jinja2 includes and imports can be used in all templates.

The path given to include/import is searched in the directory of the root template and all it’s parent directories up until the project root. Please note that the search path is not altered in included templates, meaning that it will always search in the same directories even if an include happens inside a file that was included as well.

To include/import a file relative to the currently rendered file (which is not necessarily the root template), prefix the path with ./, e.g. use {% include "./my-relative-file.j2" %}".

Macros

Jinja2 macros are fully supported. When writing macros that produce yaml resources, you must use the --- yaml separator in case you want to produce multiple resources in one go.

Why no Go Templating

kluctl started as a python project and was then migrated to be a Go project. In the python world, Jinja2 is the obvious choice when it comes to templating. In the Go world, of course Go Templates would be the first choice.

When the migration to Go was performed, it was a conscious and opinionated decision to stick with Jinja2 templating. The reason is that I (@codablock) believe that Go Templates are hard to read and write and at the same time quite limited in their features (without extensive work). It never felt natural to write Go Templates.

This “feeling” was confirmed by multiple users of kluctl when it started and users described as “relieving” to not be forced to use Go Templates.

The above is my personal experience and opinion. I’m still quite open for contributions in regard to Go Templating support, as long as Jinja2 support is kept.

1.3.1 - Predefined Variables

There are multiple variables available which are pre-defined by kluctl. These are:

args

This is a dictionary of arguments given via command line. It contains every argument defined in deployment args .

target

This is the target definition of the currently processed target. It contains all values found in the target definition , for example target.name.

images

This global object provides the dynamic images features described in images .

1.3.2 - Variable Sources

There are multiple places in deployment projects (deployment.yaml) where additional variables can be loaded into future Jinja2 contexts.

The first place where vars can be specified is the deployment root, as documented here . These vars are visible for all deployments inside the deployment project, including sub-deployments from includes.

The second place to specify variables is in the deployment items, as documented here .

The variables loaded for each entry in vars are not available inside the deployment.yaml file itself. However, each entry in vars can use all variables defined before that specific entry is processed. Consider the following example.

vars:
- file: vars1.yaml
- file: vars2.yaml
- file: optional-vars.yaml
  ignoreMissing: true
- file: default-vars.yaml
  noOverride: true
- file: vars3.yaml
  when: some.var == "value"
- file: vars3.yaml
  sensitive: true

vars2.yaml can now use variables that are defined in vars1.yaml. A special case is the use of previously defined variables inside values vars sources. Please see the documentation of values for details.

At all times, variables defined by parents of the current sub-deployment project can be used in the current vars file.

Each variable source can have the optional field ignoreMissing set to true, causing Kluctl to ignore if the source can not be found.

When specifying noOverride: true, Kluctl will not override variables from the previously loaded variables. This is useful if you want to load default values for variables.

Variables can also be loaded conditionally by specifying a condition via when: <condition>. The condition must be in the same format as described in conditional deployment items

Specifying sensitive: true causes the Webui to redact the underlying variables for non-admin users. This will be set to true by default for all variable sources that usually load sensitive data, including sops encrypted files and Kubernetes secrets.

Different types of vars entries are possible:

file

This loads variables from a yaml file. Assume the following yaml file with the name vars1.yaml:

my_vars:
  a: 1
  b: "b"
  c:
    - l1
    - l2

This file can be loaded via:

vars:
  - file: vars1.yaml

After which all included deployments and sub-deployments can use the jinja2 variables from vars1.yaml.

Kluctl also supports variable files encrypted with SOPS . See the sops integration integration for more details.

values

An inline definition of variables. Example:

vars:
  - values:
      a: 1
      b: c

These variables can then be used in all deployments and sub-deployments.

In case you need to use variables defined in previous vars sources, the values var source needs some special handling in regard to templating. It’s important to understand that the deployment project is rendered BEFORE any vars source processing is performed, which means that it will fail to render when you use previously defined variables in a values vars source. To still use previously defined variables, surround the values vars source with {% raw %} and {% endraw %}. In addition, the template expressions must be wrapped with ", as otherwise the loading of the deployment project will fail shortly after rendering due to YAML parsing errors.

vars:
  - values:
      a: 1
      b: c
{% raw %}
  - values:
      c: "{{ a }}"
{% endraw %}

An alternative syntax is to use a template expression that itself outputs a template expression:

vars:
  - values:
      a: 1
      b: c
  - values:
      c: {{ '{{ a }}' }}

The advantage of the second method is that the type (number) of a is preserved, while the first method would convert it into a string.

git

This loads variables from a git repository. Example:

vars:
  - git:
      url: ssh://git@github.com/example/repo.git
      ref:
        branch: my-branch
      path: path/to/vars.yaml

The ref field has the same format at found in Git includes

Kluctl also supports variable files encrypted with SOPS . See the sops integration integration for more details.

clusterConfigMap

Loads a configmap from the target’s cluster and loads the specified key’s value into the templating context. The value is treated and loaded as YAML and thus can either be a simple value or a complex nested structure. In case of a simple value (e.g. a number), you must also specify targetPath.

The referred ConfigMap must already exist while the Kluctl project is loaded, meaning that it is not possible to use a ConfigMap that is deployed as part of the Kluctl project itself.

Assume the following ConfigMap to be already deployed to the target cluster:

apiVersion: v1
kind: ConfigMap
metadata:
  name: my-vars
  namespace: my-namespace
data:
  vars: |
    a: 1
    b: "b"
    c:
      - l1
      - l2    

This ConfigMap can be loaded via:

vars:
  - clusterConfigMap:
      name: my-vars
      namespace: my-namespace
      key: vars

The following example uses a simple value:

apiVersion: v1
kind: ConfigMap
metadata:
  name: my-vars
  namespace: my-namespace
data:
  value: 123

This ConfigMap can be loaded via:

vars:
  - clusterConfigMap:
      name: my-vars
      namespace: my-namespace
      key: value
      targetPath: deep.nested.path

clusterSecret

Same as clusterConfigMap, but for secrets.

http

The http variables source allows to load variables from an arbitrary HTTP resource by performing a GET (or any other configured HTTP method) on the URL. Example:

vars:
  - http:
      url: https://example.com/path/to/my/vars

The above source will load a variables file from the given URL. The file is expected to be in yaml or json format.

The following additional properties are supported for http sources:

method

Specifies the HTTP method to be used when requesting the given resource. Defaults to GET.

body

The body to send along with the request. If not specified, nothing is sent.

headers

A map of key/values pairs representing the header entries to be added to the request. If not specified, nothing is added.

jsonPath

Can be used to select a nested element from the yaml/json document returned by the HTTP request. This is useful in case some REST api is used which does not directly return the variables file. Example:

vars:
  - http:
      url: https://example.com/path/to/my/vars
      jsonPath: $[0].data

The above example would successfully use the following json document as variables source:

[{"data": {"vars": {"var1": "value1"}}}]

Authentication

Kluctl currently supports BASIC and NTLM authentication. It will prompt for credentials when needed.

awsSecretsManager

AWS Secrets Manager integration. Loads a variables YAML from an AWS Secrets Manager secret. The secret can either be specified via an ARN or via a secretName and region combination. An existing AWS config profile can also be specified.

The secrets stored in AWS Secrets manager must contain a valid yaml or json file.

Example using an ARN:

vars:
  - awsSecretsManager:
      secretName: arn:aws:secretsmanager:eu-central-1:12345678:secret:secret-name-XYZ
      profile: my-prod-profile

Example using a secret name and region:

vars:
  - awsSecretsManager:
      secretName: secret-name
      region: eu-central-1
      profile: my-prod-profile

The advantage of the latter is that the auto-generated suffix in the ARN (which might not be known at the time of writing the configuration) doesn’t have to be specified.

vault

Vault by HashiCorp with Tokens authentication integration. The address and the path to the secret can be configured. The implementation was tested with KV Secrets Engine.

Example using vault:

vars:
  - vault:
      address: http://localhost:8200
      path: secret/data/simple

Before deploying please make sure that you have access to vault. You can do this for example by setting the environment variable VAULT_TOKEN.

systemEnvVars

Load variables from environment variables. Children of systemEnvVars can be arbitrary yaml, e.g. dictionaries or lists. The leaf values are used to get a value from the system environment.

Example:

vars:
- systemEnvVars:
    var1: ENV_VAR_NAME1
    someDict:
      var2: ENV_VAR_NAME2
    someList:
      - var3: ENV_VAR_NAME3

The above example will make 3 variables available: var1, someDict.var2 and someList[0].var3, each having the values of the environment variables specified by the leaf values.

All specified environment variables must be set before calling kluctl unless a default value is set. Default values can be set by using the ENV_VAR_NAME:default-value form.

Example:

vars:
- systemEnvVars:
    var1: ENV_VAR_NAME4:defaultValue

The above example will set the variable var1 to defaultValue in case ENV_VAR_NAME4 is not set.

All values retrieved from environment variables (or specified as default values) will be treated as YAML, meaning that integers and booleans will be treated as integers/booleans. If you want to enforce strings, encapsulate the values in quotes.

Example:

vars:
- systemEnvVars:
    var1: ENV_VAR_NAME5:'true'

The above example will treat true as a string instead of a boolean. When the environment variable is set outside kluctl, it should also contain the quotes. Please note that your shell might require escaping to properly pass quotes.

1.3.3 - Filters

In addition to the builtin Jinja2 filters , kluctl provides a few additional filters:

b64encode

Encodes the input value as base64. Example: {{ "test" | b64encode }} will result in dGVzdA==.

b64decode

Decodes an input base64 encoded string. Example {{ my.source.var | b64decode }}.

from_yaml

Parses a yaml string and returns an object. Please note that json is valid yaml, meaning that you can also use this filter to parse json.

to_yaml

Converts a variable/object into its yaml representation. Please note that in most cases the resulting string will not be properly indented, which will require you to also use the indent filter. Example:

apiVersion: v1
kind: ConfigMap
metadata:
  name: my-config
data:
  config.yaml: |
        {{ my_config | to_yaml | indent(4) }}

to_json

Same as to_yaml, but with json as output. Please note that json is always valid yaml, meaning that you can also use to_json in yaml files. Consider the following example:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-deployment
spec:
  template:
    spec:
      containers:
      - name: c1
        image: my-image
        env: {{ my_list_of_env_entries | to_json }}

This would render json into a yaml file, which is still a valid yaml file. Compare this to how this would have to be solved with to_yaml:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-deployment
spec:
  template:
    spec:
      containers:
      - name: c1
        image: my-image
        env:
          {{ my_list_of_env_entries | to_yaml | indent(10) }}

The required indention filter is the part that makes this error-prone and hard to maintain. Consider using to_json whenever you can.

render

Renders the input string with the current Jinja2 context. Example:

{% set a="{{ my_var }}" %}
{{ a | render }}

sha256(digest_len)

Calculates the sha256 digest of the input string. Example:

{{ "some-string" | sha256 }}

digest_len is an optional parameter that allows to limit the length of the returned hex digest. Example:

{{ "some-string" | sha256(6) }}

slugify

Slugify a string based on python-slugify .

1.3.4 - Functions

In addition to the provided builtin global functions , kluctl also provides a few global functions:

load_template(file)

Loads the given file into memory, renders it with the current Jinja2 context and then returns it as a string. Example:

{% set a=load_template('file.yaml') %}
{{ a }}

load_template uses the same path searching rules as described in includes/imports .

load_sha256(file, digest_len)

Loads the given file into memory, renders it and calculates the sha256 hash of the result.

The filename given to load_sha256 is treated the same as in load_template. Recursive loading/calculating of hashes is allowed and is solved by replacing load_sha256 invocations with currently loaded templates with dummy strings. This also allows to calculate the hash of the currently rendered template, for example:

apiVersion: v1
kind: ConfigMap
metadata:
  name: my-config-{{ load_sha256("configmap.yaml") }}
data:

digest_len is an optional parameter that allows to limit the length of the returned hex digest.

get_var(field_path, default)

Convenience method to navigate through the current context variables via a JSON Path . Let’s assume you currently have these variables defined (e.g. via vars ):

my:
  deep:
    var: value

Then {{ get_var('my.deep.var', 'my-default') }} would return value. When any of the elements inside the field path are non-existent, the given default value is returned instead.

The field_path parameter can also be a list of pathes, which are then tried one after the another, returning the first result that gives a value that is not None. For example, {{ get_var(['non.existing.var', my.deep.var'], 'my-default') }} would also return value.

merge_dict(d1, d2)

Clones d1 and then recursively merges d2 into it and returns the result. Values inside d2 will override values in d1.

update_dict(d1, d2)

Same as merge_dict, but merging is performed in-place into d1.

raise(msg)

Raises a python exception with the given message. This causes the current command to abort.

debug_print(msg)

Prints a line to stderr.

time.now()

Returns the current time. The returned object has the following members:

time.utcnow()

Returns the current time in UTC. The object has the same members as described in time.now() .

time.parse_iso(iso_time_str)

Parse the given string and return a time object. The string must be in ISO time. The object has the same members as described in time.now() .

time.second, time.minute, time.hour

Represents a time delta to be used with t + delta and t - delta. Example

{{ time.now() + time.minute * 10 }}

1.4 - Commands

kluctl offers a unified command line interface that allows to standardize all your deployments. Every project, no matter how different it is from other projects, is managed the same way.

You can always call kluctl --help or kluctl <command> --help for a help prompt.

Individual commands are documented in sub-sections.

1.4.1 - Common Arguments

A few sets of arguments are common between multiple commands. These arguments are still part of the command itself and must be placed after the command name.

Global arguments

These arguments are available for all commands.

Global arguments:
      --cpu-profile string       Enable CPU profiling and write the result to the given path
      --debug                    Enable debug logging
      --gops-agent               Start gops agent in the background
      --gops-agent-addr string   Specify the address:port to use for the gops agent (default "127.0.0.1:0")
      --no-color                 Disable colored output
      --no-update-check          Disable update check on startup

Project arguments

These arguments are available for all commands that are based on a Kluctl project. They control where and how to load the kluctl project and deployment project.

Project arguments:
  Define where and how to load the kluctl project and its components from.

  -a, --arg stringArray                        Passes a template argument in the form of name=value. Nested args
                                               can be set with the '-a my.nested.arg=value' syntax. Values are
                                               interpreted as yaml values, meaning that 'true' and 'false' will
                                               lead to boolean values and numbers will be treated as numbers. Use
                                               quotes if you want these to be treated as strings. If the value
                                               starts with @, it is treated as a file, meaning that the contents
                                               of the file will be loaded and treated as yaml.
      --args-from-file stringArray             Loads a yaml file and makes it available as arguments, meaning that
                                               they will be available thought the global 'args' variable.
      --context string                         Overrides the context name specified in the target. If the selected
                                               target does not specify a context or the no-name target is used,
                                               --context will override the currently active context.
      --git-cache-update-interval duration     Specify the time to wait between git cache updates. Defaults to not
                                               wait at all and always updating caches.
      --local-git-group-override stringArray   Same as --local-git-override, but for a whole group prefix instead
                                               of a single repository. All repositories that have the given prefix
                                               will be overridden with the given local path and the repository
                                               suffix appended. For example,
                                               'gitlab.com/some-org/sub-org=/local/path/to/my-forks' will override
                                               all repositories below 'gitlab.com/some-org/sub-org/' with the
                                               repositories found in '/local/path/to/my-forks'. It will however
                                               only perform an override if the given repository actually exists
                                               locally and otherwise revert to the actual (non-overridden) repository.
      --local-git-override stringArray         Specify a single repository local git override in the form of
                                               'github.com/my-org/my-repo=/local/path/to/override'. This will
                                               cause kluctl to not use git to clone for the specified repository
                                               but instead use the local directory. This is useful in case you
                                               need to test out changes in external git repositories without
                                               pushing them.
  -c, --project-config existingfile            Location of the .kluctl.yaml config file. Defaults to
                                               $PROJECT/.kluctl.yaml
      --project-dir existingdir                Specify the project directory. Defaults to the current working
                                               directory.
  -t, --target string                          Target name to run command for. Target must exist in .kluctl.yaml.
  -T, --target-name-override string            Overrides the target name. If -t is used at the same time, then the
                                               target will be looked up based on -t <name> and then renamed to the
                                               value of -T. If no target is specified via -t, then the no-name
                                               target is renamed to the value of -T.
      --timeout duration                       Specify timeout for all operations, including loading of the
                                               project, all external api calls and waiting for readiness. (default
                                               10m0s)

Image arguments

These arguments are available on some target based commands. They control image versions requested by images.get_image(...) calls .

Image arguments:
  Control fixed images and update behaviour.

  -F, --fixed-image stringArray          Pin an image to a given version. Expects
                                         '--fixed-image=image<:namespace:deployment:container>=result'
      --fixed-images-file existingfile   Use .yaml file to pin image versions. See output of list-images
                                         sub-command or read the documentation for details about the output format

Inclusion/Exclusion arguments

These arguments are available for some target based commands. They control inclusion/exclusion based on tags and deployment item pathes.

Inclusion/Exclusion arguments:
  Control inclusion/exclusion.

      --exclude-deployment-dir stringArray   Exclude deployment dir. The path must be relative to the root
                                             deployment project. Exclusion has precedence over inclusion, same as
                                             in --exclude-tag
  -E, --exclude-tag stringArray              Exclude deployments with given tag. Exclusion has precedence over
                                             inclusion, meaning that explicitly excluded deployments will always
                                             be excluded even if an inclusion rule would match the same deployment.
      --include-deployment-dir stringArray   Include deployment dir. The path must be relative to the root
                                             deployment project.
  -I, --include-tag stringArray              Include deployments with given tag.

Command Results arguments

These arguments control how command results are stored.

Command Results:
  Configure how command results are stored.

      --command-result-namespace string   Override the namespace to be used when writing command results. (default
                                          "kluctl-results")
      --force-write-command-result        Force writing of command results, even if the command is run in dry-run mode.
      --keep-command-results-count int    Configure how many old command results to keep. (default 5)
      --keep-validate-results-count int   Configure how many old validate results to keep. (default 2)
      --write-command-result              Enable writing of command results into the cluster. This is enabled by
                                          default. (default true)

1.4.2 - Environment Variables

In addition to arguments, Kluctl can be controlled via a set of environment variables.

Environment variables as arguments

All options/arguments accepted by kluctl can also be specified via environment variables. The name of the environment variables always start with KLUCTL_ and end with the option/argument in uppercase and dashes replaced with underscores. As an example, --dry-run can also be specified with the environment variable KLUCTL_DRY_RUN=true.

If an argument needs to be specified multiple times through environment variables, indexed can be appended to the names of the environment variables, e.g. KLUCTL_ARG_0=name1=value1 and KLUCTL_ARG_1=name2=value2.

Additional environment variables

A few additional environment variables are supported which do not belong to an option/argument. These are:

1. KLUCTL_REGISTRY_<idx>_HOST, KLUCTL_REGISTRY_<idx>_USERNAME, and so on. See registries for details.
2. KLUCTL_GIT_<idx>_HOST, KLUCTL_GIT_<idx>_USERNAME, and so on.
3. KLUCTL_SSH_DISABLE_STRICT_HOST_KEY_CHECKING. Disable ssh host key checking when accessing git repositories.

1.4.3 - controller install

Command

Usage: kluctl controller install [flags]

Install the Kluctl controller This command will install the kluctl-controller to the current Kubernetes clusters.

Arguments

The following sets of arguments are available:

1. command results arguments

In addition, the following arguments are available:

Misc arguments:
  Command specific arguments.

      --context string          Override the context to use.
      --dry-run                 Performs all kubernetes API calls in dry-run mode.
      --kluctl-version string   Specify the controller version to install.
  -y, --yes                     Suppresses 'Are you sure?' questions and proceeds as if you would answer 'yes'.

1.4.4 - controller run

Command

Usage: kluctl controller run [flags]

Run the Kluctl controller This command will run the Kluctl Controller. This is usually meant to be run inside a cluster and not from your local machine.

Arguments

The following arguments are available:

Misc arguments:
  Command specific arguments.

      --concurrency int                    Configures how many KluctlDeployments can be be reconciled
                                           concurrently. (default 4)
      --context string                     Override the context to use.
      --default-service-account string     Default service account used for impersonation.
      --dry-run                            Run all deployments in dryRun=true mode.
      --health-probe-bind-address string   The address the probe endpoint binds to. (default ":8081")
      --kubeconfig string                  Override the kubeconfig to use.
      --leader-elect                       Enable leader election for controller manager. Enabling this will
                                           ensure there is only one active controller manager.
      --metrics-bind-address string        The address the metric endpoint binds to. (default ":8080")

1.4.5 - delete

Command

Usage: kluctl delete [flags]

Delete a target (or parts of it) from the corresponding cluster Objects are located based on the target discriminator.

WARNING: This command will also delete objects which are not part of your deployment project (anymore). It really only decides based on the discriminator and does NOT take the local target/state into account!

Arguments

The following sets of arguments are available:

1. project arguments
2. image arguments
3. inclusion/exclusion arguments
4. command results arguments

In addition, the following arguments are available:

Misc arguments:
  Command specific arguments.

      --discriminator string                        Override the discriminator used to find objects for deletion.
      --dry-run                                     Performs all kubernetes API calls in dry-run mode.
      --helm-insecure-skip-tls-verify stringArray   Controls skipping of TLS verification. Must be in the form
                                                    --helm-insecure-skip-tls-verify=<credentialsId>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-key-file stringArray                   Specify client certificate to use for Helm Repository
                                                    authentication. Must be in the form
                                                    --helm-key-file=<credentialsId>:<path>, where <credentialsId>
                                                    must match the id specified in the helm-chart.yaml.
      --helm-password stringArray                   Specify password to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-password=<credentialsId>:<password>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-username stringArray                   Specify username to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-username=<credentialsId>:<username>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --no-obfuscate                                Disable obfuscation of sensitive/secret data
  -o, --output-format stringArray                   Specify output format and target file, in the format
                                                    'format=path'. Format can either be 'text' or 'yaml'. Can be
                                                    specified multiple times. The actual format for yaml is
                                                    currently not documented and subject to change.
      --render-output-dir string                    Specifies the target directory to render the project into. If
                                                    omitted, a temporary directory is used.
      --short-output                                When using the 'text' output format (which is the default),
                                                    only names of changes objects are shown instead of showing all
                                                    changes.
  -y, --yes                                         Suppresses 'Are you sure?' questions and proceeds as if you
                                                    would answer 'yes'.

They have the same meaning as described in deploy .

1.4.6 - deploy

Command

Usage: kluctl deploy [flags]

Deploys a target to the corresponding cluster This command will also output a diff between the initial state and the state after deployment. The format of this diff is the same as for the ‘diff’ command. It will also output a list of prunable objects (without actually deleting them).

Arguments

The following sets of arguments are available:

1. project arguments
2. image arguments
3. inclusion/exclusion arguments
4. command results arguments

In addition, the following arguments are available:

Misc arguments:
  Command specific arguments.

      --abort-on-error                              Abort deploying when an error occurs instead of trying the
                                                    remaining deployments
      --dry-run                                     Performs all kubernetes API calls in dry-run mode.
      --force-apply                                 Force conflict resolution when applying. See documentation for
                                                    details
      --force-replace-on-error                      Same as --replace-on-error, but also try to delete and
                                                    re-create objects. See documentation for more details.
      --helm-insecure-skip-tls-verify stringArray   Controls skipping of TLS verification. Must be in the form
                                                    --helm-insecure-skip-tls-verify=<credentialsId>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-key-file stringArray                   Specify client certificate to use for Helm Repository
                                                    authentication. Must be in the form
                                                    --helm-key-file=<credentialsId>:<path>, where <credentialsId>
                                                    must match the id specified in the helm-chart.yaml.
      --helm-password stringArray                   Specify password to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-password=<credentialsId>:<password>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-username stringArray                   Specify username to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-username=<credentialsId>:<username>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --no-obfuscate                                Disable obfuscation of sensitive/secret data
      --no-wait                                     Don't wait for objects readiness'
  -o, --output-format stringArray                   Specify output format and target file, in the format
                                                    'format=path'. Format can either be 'text' or 'yaml'. Can be
                                                    specified multiple times. The actual format for yaml is
                                                    currently not documented and subject to change.
      --prune                                       Prune orphaned objects directly after deploying. See the help
                                                    for the 'prune' sub-command for details.'
      --readiness-timeout duration                  Maximum time to wait for object readiness. The timeout is
                                                    meant per-object. Timeouts are in the duration format (1s, 1m,
                                                    1h, ...). If not specified, a default timeout of 5m is used.
                                                    (default 5m0s)
      --render-output-dir string                    Specifies the target directory to render the project into. If
                                                    omitted, a temporary directory is used.
      --replace-on-error                            When patching an object fails, try to replace it. See
                                                    documentation for more details.
      --short-output                                When using the 'text' output format (which is the default),
                                                    only names of changes objects are shown instead of showing all
                                                    changes.
  -y, --yes                                         Suppresses 'Are you sure?' questions and proceeds as if you
                                                    would answer 'yes'.

–force-apply

kluctl implements deployments via server-side apply and a custom automatic conflict resolution algorithm. This algurithm is an automatic implementation of the “ Don’t overwrite value, give up management claim ” method. It should work in most cases, but might still fail. In case of such failure, you can use --force-apply to use the “Overwrite value, become sole manager” strategy instead.

Please note that this is a risky operation which might overwrite fields which were initially managed by kluctl but were then overtaken by other managers (e.g. by operators). Always use this option with caution and perform a dry-run before to ensure nothing unexpected gets overwritten.

–replace-on-error

In some situations, patching Kubernetes objects might fail for different reasons. In such cases, you can try --replace-on-error to instruct kluctl to retry with an update operation.

Please note that this will cause all fields to be overwritten, even if owned by other field managers.

–force-replace-on-error

This flag will cause the same replacement attempt on failure as with --replace-on-error. In addition, it will fallback to a delete+recreate operation in case the replace also fails.

Please note that this is a potentially risky operation, especially when an object carries some kind of important state.

–abort-on-error

kluctl does not abort a command when an individual object fails can not be updated. It collects all errors and warnings and outputs them instead. This option modifies the behaviour to immediately abort the command.

1.4.7 - diff

Command

Usage: kluctl diff [flags]

Perform a diff between the locally rendered target and the already deployed target The output is by default in human readable form (a table combined with unified diffs). The output can also be changed to output a yaml file. Please note however that the format is currently not documented and prone to changes. After the diff is performed, the command will also search for prunable objects and list them.

Arguments

The following sets of arguments are available:

1. project arguments
2. image arguments
3. inclusion/exclusion arguments

In addition, the following arguments are available:

Misc arguments:
  Command specific arguments.

      --force-apply                                 Force conflict resolution when applying. See documentation for
                                                    details
      --force-replace-on-error                      Same as --replace-on-error, but also try to delete and
                                                    re-create objects. See documentation for more details.
      --helm-insecure-skip-tls-verify stringArray   Controls skipping of TLS verification. Must be in the form
                                                    --helm-insecure-skip-tls-verify=<credentialsId>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-key-file stringArray                   Specify client certificate to use for Helm Repository
                                                    authentication. Must be in the form
                                                    --helm-key-file=<credentialsId>:<path>, where <credentialsId>
                                                    must match the id specified in the helm-chart.yaml.
      --helm-password stringArray                   Specify password to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-password=<credentialsId>:<password>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-username stringArray                   Specify username to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-username=<credentialsId>:<username>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --ignore-annotations                          Ignores changes in annotations when diffing
      --ignore-labels                               Ignores changes in labels when diffing
      --ignore-tags                                 Ignores changes in tags when diffing
      --no-obfuscate                                Disable obfuscation of sensitive/secret data
  -o, --output-format stringArray                   Specify output format and target file, in the format
                                                    'format=path'. Format can either be 'text' or 'yaml'. Can be
                                                    specified multiple times. The actual format for yaml is
                                                    currently not documented and subject to change.
      --render-output-dir string                    Specifies the target directory to render the project into. If
                                                    omitted, a temporary directory is used.
      --replace-on-error                            When patching an object fails, try to replace it. See
                                                    documentation for more details.
      --short-output                                When using the 'text' output format (which is the default),
                                                    only names of changes objects are shown instead of showing all
                                                    changes.

--force-apply and --replace-on-error have the same meaning as in deploy .

1.4.8 - helm-pull

Command

Usage: kluctl helm-pull [flags]

Recursively searches for ‘helm-chart.yaml’ files and pre-pulls the specified Helm charts Kluctl requires Helm Charts to be pre-pulled by default, which is handled by this command. It will collect all required Charts and versions and pre-pull them into .helm-charts. To disable pre-pulling for individual charts, set ‘skipPrePull: true’ in helm-chart.yaml.

See helm-integration for more details.

Arguments

The following sets of arguments are available:

1. project arguments (except -a)

1.4.9 - helm-update

Command

Usage: kluctl helm-update [flags]

Recursively searches for ‘helm-chart.yaml’ files and checks for new available versions Optionally performs the actual upgrade and/or add a commit to version control.

Arguments

The following sets of arguments are available:

1. project arguments (except -a)

In addition, the following arguments are available:

Misc arguments:
  Command specific arguments.

      --commit                                      Create a git commit for every updated chart
      --helm-insecure-skip-tls-verify stringArray   Controls skipping of TLS verification. Must be in the form
                                                    --helm-insecure-skip-tls-verify=<credentialsId>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-key-file stringArray                   Specify client certificate to use for Helm Repository
                                                    authentication. Must be in the form
                                                    --helm-key-file=<credentialsId>:<path>, where <credentialsId>
                                                    must match the id specified in the helm-chart.yaml.
      --helm-password stringArray                   Specify password to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-password=<credentialsId>:<password>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-username stringArray                   Specify username to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-username=<credentialsId>:<username>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
  -i, --interactive                                 Ask for every Helm Chart if it should be upgraded.
      --upgrade                                     Write new versions into helm-chart.yaml and perform helm-pull
                                                    afterwards

1.4.10 - list-images

Command

Usage: kluctl list-images [flags]

Renders the target and outputs all images used via ‘images.get_image(…) The result is a compatible with yaml files expected by –fixed-images-file.

If fixed images (’-f/–fixed-image’) are provided, these are also taken into account, as described in the deploy command.

Arguments

The following sets of arguments are available:

1. project arguments
2. image arguments
3. inclusion/exclusion arguments

In addition, the following arguments are available:

Misc arguments:
  Command specific arguments.

      --helm-insecure-skip-tls-verify stringArray   Controls skipping of TLS verification. Must be in the form
                                                    --helm-insecure-skip-tls-verify=<credentialsId>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-key-file stringArray                   Specify client certificate to use for Helm Repository
                                                    authentication. Must be in the form
                                                    --helm-key-file=<credentialsId>:<path>, where <credentialsId>
                                                    must match the id specified in the helm-chart.yaml.
      --helm-password stringArray                   Specify password to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-password=<credentialsId>:<password>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-username stringArray                   Specify username to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-username=<credentialsId>:<username>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --kubernetes-version string                   Specify the Kubernetes version that will be assumed. This will
                                                    also override the kubeVersion used when rendering Helm Charts.
      --offline-kubernetes                          Run command in offline mode, meaning that it will not try to
                                                    connect the target cluster
  -o, --output stringArray                          Specify output target file. Can be specified multiple times
      --render-output-dir string                    Specifies the target directory to render the project into. If
                                                    omitted, a temporary directory is used.
      --simple                                      Output a simplified version of the images list

1.4.11 - list-targets

Command

Usage: kluctl list-targets [flags]

Outputs a yaml list with all targets Outputs a yaml list with all targets

Arguments

The following arguments are available:

Misc arguments:
  Command specific arguments.

  -o, --output stringArray   Specify output target file. Can be specified multiple times

1.4.12 - poke-images

Command

Usage: kluctl poke-images [flags]

Replace all images in target This command will fully render the target and then only replace images instead of fully deploying the target. Only images used in combination with ‘images.get_image(…)’ are replaced

Arguments

The following sets of arguments are available:

1. project arguments
2. image arguments
3. inclusion/exclusion arguments
4. command results arguments

In addition, the following arguments are available:

Misc arguments:
  Command specific arguments.

      --dry-run                                     Performs all kubernetes API calls in dry-run mode.
      --helm-insecure-skip-tls-verify stringArray   Controls skipping of TLS verification. Must be in the form
                                                    --helm-insecure-skip-tls-verify=<credentialsId>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-key-file stringArray                   Specify client certificate to use for Helm Repository
                                                    authentication. Must be in the form
                                                    --helm-key-file=<credentialsId>:<path>, where <credentialsId>
                                                    must match the id specified in the helm-chart.yaml.
      --helm-password stringArray                   Specify password to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-password=<credentialsId>:<password>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-username stringArray                   Specify username to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-username=<credentialsId>:<username>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --no-obfuscate                                Disable obfuscation of sensitive/secret data
  -o, --output-format stringArray                   Specify output format and target file, in the format
                                                    'format=path'. Format can either be 'text' or 'yaml'. Can be
                                                    specified multiple times. The actual format for yaml is
                                                    currently not documented and subject to change.
      --render-output-dir string                    Specifies the target directory to render the project into. If
                                                    omitted, a temporary directory is used.
      --short-output                                When using the 'text' output format (which is the default),
                                                    only names of changes objects are shown instead of showing all
                                                    changes.
  -y, --yes                                         Suppresses 'Are you sure?' questions and proceeds as if you
                                                    would answer 'yes'.

1.4.13 - prune

Command

Usage: kluctl prune [flags]

Searches the target cluster for prunable objects and deletes them

Arguments

The following sets of arguments are available:

1. project arguments
2. image arguments
3. inclusion/exclusion arguments
4. command results arguments

In addition, the following arguments are available:

Misc arguments:
  Command specific arguments.

      --dry-run                                     Performs all kubernetes API calls in dry-run mode.
      --helm-insecure-skip-tls-verify stringArray   Controls skipping of TLS verification. Must be in the form
                                                    --helm-insecure-skip-tls-verify=<credentialsId>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-key-file stringArray                   Specify client certificate to use for Helm Repository
                                                    authentication. Must be in the form
                                                    --helm-key-file=<credentialsId>:<path>, where <credentialsId>
                                                    must match the id specified in the helm-chart.yaml.
      --helm-password stringArray                   Specify password to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-password=<credentialsId>:<password>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-username stringArray                   Specify username to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-username=<credentialsId>:<username>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --no-obfuscate                                Disable obfuscation of sensitive/secret data
  -o, --output-format stringArray                   Specify output format and target file, in the format
                                                    'format=path'. Format can either be 'text' or 'yaml'. Can be
                                                    specified multiple times. The actual format for yaml is
                                                    currently not documented and subject to change.
      --render-output-dir string                    Specifies the target directory to render the project into. If
                                                    omitted, a temporary directory is used.
      --short-output                                When using the 'text' output format (which is the default),
                                                    only names of changes objects are shown instead of showing all
                                                    changes.
  -y, --yes                                         Suppresses 'Are you sure?' questions and proceeds as if you
                                                    would answer 'yes'.

They have the same meaning as described in deploy .

1.4.14 - render

Command

Usage: kluctl render [flags]

Renders all resources and configuration files Renders all resources and configuration files and stores the result in either a temporary directory or a specified directory.

Arguments

The following sets of arguments are available:

1. project arguments
2. image arguments
3. inclusion/exclusion arguments

In addition, the following arguments are available:

Misc arguments:
  Command specific arguments.

      --helm-insecure-skip-tls-verify stringArray   Controls skipping of TLS verification. Must be in the form
                                                    --helm-insecure-skip-tls-verify=<credentialsId>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-key-file stringArray                   Specify client certificate to use for Helm Repository
                                                    authentication. Must be in the form
                                                    --helm-key-file=<credentialsId>:<path>, where <credentialsId>
                                                    must match the id specified in the helm-chart.yaml.
      --helm-password stringArray                   Specify password to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-password=<credentialsId>:<password>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-username stringArray                   Specify username to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-username=<credentialsId>:<username>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --kubernetes-version string                   Specify the Kubernetes version that will be assumed. This will
                                                    also override the kubeVersion used when rendering Helm Charts.
      --offline-kubernetes                          Run command in offline mode, meaning that it will not try to
                                                    connect the target cluster
      --print-all                                   Write all rendered manifests to stdout
      --render-output-dir string                    Specifies the target directory to render the project into. If
                                                    omitted, a temporary directory is used.

1.4.15 - validate

Command

Usage: kluctl validate [flags]

Validates the already deployed deployment This means that all objects are retrieved from the cluster and checked for readiness.

TODO: This needs to be better documented!

Arguments

The following sets of arguments are available:

1. project arguments
2. image arguments

In addition, the following arguments are available:

Misc arguments:
  Command specific arguments.

      --helm-insecure-skip-tls-verify stringArray   Controls skipping of TLS verification. Must be in the form
                                                    --helm-insecure-skip-tls-verify=<credentialsId>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-key-file stringArray                   Specify client certificate to use for Helm Repository
                                                    authentication. Must be in the form
                                                    --helm-key-file=<credentialsId>:<path>, where <credentialsId>
                                                    must match the id specified in the helm-chart.yaml.
      --helm-password stringArray                   Specify password to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-password=<credentialsId>:<password>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
      --helm-username stringArray                   Specify username to use for Helm Repository authentication.
                                                    Must be in the form
                                                    --helm-username=<credentialsId>:<username>, where
                                                    <credentialsId> must match the id specified in the helm-chart.yaml.
  -o, --output stringArray                          Specify output target file. Can be specified multiple times
      --render-output-dir string                    Specifies the target directory to render the project into. If
                                                    omitted, a temporary directory is used.
      --sleep duration                              Sleep duration between validation attempts (default 5s)
      --wait duration                               Wait for the given amount of time until the deployment validates
      --warnings-as-errors                          Consider warnings as failures

1.4.16 - webui build

Command

Usage: kluctl webui build [flags]

Build the static Kluctl Webui This command will build the static Kluctl Webui.

Arguments

The following arguments are available:

Misc arguments:
  Command specific arguments.

      --all-contexts          Use all Kubernetes contexts found in the kubeconfig.
      --context stringArray   List of kubernetes contexts to use. Defaults to the current context.
      --max-results int       Specify the maximum number of results per target. (default 1)
      --path string           Output path.

1.4.17 - webui run

Command

Usage: kluctl webui run [flags]

Run the Kluctl Webui

Arguments

The following arguments are available:

Misc arguments:
  Command specific arguments.

      --all-contexts                Use all Kubernetes contexts found in the kubeconfig.
      --context stringArray         List of kubernetes contexts to use.
      --host string                 Host to bind to. Pass an empty string to bind to all addresses. Defaults to
                                    'localhost' when run locally and to all hosts when run in-cluster.
      --in-cluster                  This enables in-cluster functionality. This also enforces authentication.
      --in-cluster-context string   The context to use fo in-cluster functionality.
      --only-api                    Only serve API without the actual UI.
      --port int                    Port to bind to. (default 8080)

Auth arguments:
  Configure authentication.

      --auth-admin-rbac-user string            Specify the RBAC user to use for admin access. (default
                                               "kluctl-webui-admin")
      --auth-logout-return-param string        Specify the parameter name to pass to the logout redirect url,
                                               containing the return URL to redirect back.
      --auth-logout-url string                 Specify the logout URL, to which the user should be redirected
                                               after clearing the Kluctl Webui session.
      --auth-oidc-admins-group stringArray     Specify admins group names.'
      --auth-oidc-client-id string             Specify the ClientID.
      --auth-oidc-client-secret-key string     Specify the secret name for the ClientSecret. (default
                                               "oidc-client-secret")
      --auth-oidc-client-secret-name string    Specify the secret name for the ClientSecret. (default "webui-secret")
      --auth-oidc-display-name string          Specify the name of the OIDC provider to be displayed on the login
                                               page. (default "OpenID Connect")
      --auth-oidc-group-claim string           Specify claim for the groups.' (default "groups")
      --auth-oidc-issuer-url string            Specify the OIDC provider's issuer URL.
      --auth-oidc-param stringArray            Specify additional parameters to be passed to the authorize endpoint.
      --auth-oidc-redirect-url string          Specify the redirect URL.
      --auth-oidc-scope stringArray            Specify the scopes.
      --auth-oidc-user-claim string            Specify claim for the username.' (default "email")
      --auth-oidc-viewers-group stringArray    Specify viewers group names.'
      --auth-secret-key string                 Specify the secret key for the secret used for internal encryption
                                               of tokens and cookies. (default "auth-secret")
      --auth-secret-name string                Specify the secret name for the secret used for internal encryption
                                               of tokens and cookies. (default "webui-secret")
      --auth-static-admin-secret-key string    Specify the secret key for the admin password. (default
                                               "admin-password")
      --auth-static-login-enabled              Enable the admin user. (default true)
      --auth-static-login-secret-name string   Specify the secret name for the admin and viewer passwords.
                                               (default "webui-secret")
      --auth-static-viewer-secret-key string   Specify the secret key for the viewer password. (default
                                               "viewer-password")
      --auth-viewer-rbac-user string           Specify the RBAC user to use for viewer access. (default
                                               "kluctl-webui-viewer")

1.5 - Installation

Kluctl is available as a CLI and as a GitOps controller.

Installing the CLI

Binaries

The kluctl CLI is available as a binary executable for all major platforms, the binaries can be downloaded form GitHub releases page .

Installation with Homebrew

With Homebrew for macOS and Linux:

brew install kluctl/tap/kluctl

Installation with Bash

With Bash for macOS and Linux:

curl -s https://kluctl.io/install.sh | bash

The install script does the following:

• attempts to detect your OS
• downloads and unpacks the release tar file in a temporary directory
• copies the kluctl binary to /usr/local/bin
• removes the temporary directory

Build from source

Clone the repository:

git clone https://github.com/kluctl/kluctl
cd kluctl

Build the kluctl binary (requires go >= 1.19):

make build

Run the binary:

./bin/kluctl -h

Container images

A container image with kluctl is available on GitHub:

• ghcr.io/kluctl/kluctl:<version>

Installing the GitOps Controller

The controller can be installed via two available options.

Using the “install” sub-command

The kluctl controller install command can be used to install the controller. It will use an embedded version of the Controller Kluctl deployment project found here .

Using a Kluctl deployment

To manage and install the controller via Kluctl, you can use a Git include in your own deployment:

deployments:
  - git:
      url: https://github.com/kluctl/kluctl.git
      subDir: install/controller
      ref:
        tag: v2.21.2

Installing the Kluctl Webui

See Installing the Kluctl Webui for details.

1.6 - Get Started

This tutorial shows you how to start using kluctl.

Before you begin

A few things must be prepared before you actually begin.

Get a Kubernetes cluster

The first step is of course: You need a kubernetes cluster. It doesn’t really matter where this cluster is hosted, if it’s a local (e.g. kind ) cluster, managed cluster, or a self-hosted cluster, kops or kubespray based, AWS, GCE, Azure, … and so on. Kluctl is completely independent of how Kubernetes is deployed and where it is hosted.

There is however a minimum Kubernetes version that must be met: 1.20.0. This is due to the heavy use of server-side apply which was not stable enough in older versions of Kubernetes.

Prepare your kubeconfig

Your local kubeconfig should be configured to have access to the target Kubernetes cluster via a dedicated context. The context name should match with the name that you want to use for the cluster from now on. Let’s assume the name is test.example.com, then you’d have to ensure that the kubeconfig context test.example.com is correctly pointing and authorized for this cluster.

See Configure Access to Multiple Clusters for documentation on how to manage multiple clusters with a single kubeconfig. Depending on the Kubernetes provisioning/deployment tooling you used, you might also be able to directly export the context into your local kubeconfig. For example, kops is able to export and merge the kubeconfig for a given cluster.

Objectives

• Checkout one of the example Kluctl projects
• Deploy to your local cluster
• Change something and re-deploy

Install Kluctl

The kluctl command-line interface (CLI) is required to perform deployments. Read the installation instructions to figure out how to install it.

Use Kluctl with a plain Kustomize deployment

The simplest way to test out Kluctl is to use an existing Kustomize deployment and just test out the CLI. For example, try it with the podtato-head project :

$ git clone https://github.com/podtato-head/podtato-head.git
$ cd podtato-head/delivery/kustomize/base
$ kluctl deploy

Then try to modify something inside the Kustomize deployment and retry the kluctl deploy call.

Try out the Kluctl examples

For more advanced examples, check out the Kluctl example projects. Clone the example project found at https://github.com/kluctl/kluctl-examples

git clone https://github.com/kluctl/kluctl-examples.git

Choose one of the examples

You can choose whatever example you like from the cloned repository. We will however continue this guide by referring to the simple-helm example found in that repository. Change the current directory:

cd kluctl-examples/simple-helm

Create your local cluster

Create a local cluster with kind :

kind create cluster

This will update your kubeconfig to contain a context with the name kind-kind. By default, all examples will use the currently active context.

Deploy the example

Now run the following command to deploy the example:

kluctl deploy -t simple-helm

Kluctl will perform a diff first and then ask for your confirmation to deploy it. In this case, you should only see some objects being newly deployed.

kubectl -n simple-helm get pod

Change something and re-deploy

Now change something inside the deployment project. You could for example add replicaCount: 2 to deployment/nginx/helm-values.yml. After you have saved your changes, run the deploy command again:

kluctl deploy -t simple-helm

This time it should show your modifications in the diff. Confirm that you want to perform the deployment and then verify it:

kubectl -n simple-helm get pod

You should need 2 instances of the nginx POD running now.

Where to continue?

Continue by reading through the tutorials and by consulting the reference documentation .

2 - Kluctl GitOps

GitOps in Kluctl is implemented through the Kluctl Controller, which must be installed to your target cluster.

The Kluctl Controller is a Kubernetes operator which implements the KluctlDeployment custom resource. This resource allows to define a Kluctl deployment that should be constantly reconciled (re-deployed) whenever the deployment changes.

Motivation and Philosophy

Kluctl tries its best to implement all its features via Kluctl projects , meaning that the deployments are, at least theoretically, deployable from the CLI at all times. The Kluctl Controller does not add functionality on top of that and thus does not couple your deployments to a running controller.

Instead, the KluctlDeployment custom resource acts as an interface to the deployment. It tries to offer the same functionality and options as offered by the CLI, but through a custom resource instead of a CLI invocation.

As an example, arguments passed via -a arg=value can be passed to the custom resource via the spec.args field. The same applies to options like --dry-run, which equals to spec.dryRun: true in the custom resource. Check the documentation of KluctlDeployment for more such options.

Installation

Installation instructions can be found here

Design

The reconciliation process consists of multiple steps which are constantly repeated:

• clone the root Kluctl project via Git
• prepare the Kluctl deployment by rendering the whole deployment
• deploy the specified target via kluctl deploy if the rendered resources changed
• prune orphaned objects via kluctl prune
• validate the deployment status via kluctl validate

Reconciliation is performed on a configurable interval . A single reconciliation iteration will first clone and prepare the project. Only when the rendered resources indicate a change (by using a hash internally), the controller will initiate a deployment. After the deployment, the controller will also perform pruning (only if prune: true is set).

When the KluctlDeployment is removed from the cluster, the controller cal also delete all resources belonging to that deployment. This will only happen if delete: true is set.

Deletion and pruning is based on the discriminator of the given target.

A KluctlDeployment can be suspended . While suspended, the controller will skip reconciliation, including deletion and pruning.

The API design of the controller can be found at kluctldeployment.gitops.kluctl.io/v1beta1 .

Example

After installing the Kluctl Controller, we can create a KluctlDeployment that automatically deploys the Microservices Demo .

Create a KluctlDeployment that uses the demo project source to deploy the test target to the same cluster that the controller runs on.

apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: microservices-demo-test
  namespace: kluctl-system
spec:
  interval: 10m
  source:
    url: https://github.com/kluctl/kluctl-examples.git
    path: "./microservices-demo/3-templating-and-multi-env/"
  timeout: 2m
  target: test
  context: default
  prune: true

This example will deploy a fully-fledged microservices application with multiple backend services, frontends and databases, all via one single KluctlDeployment.

To deploy the same Kluctl project to another target (e.g. prod), simply create the following resource.

apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: microservices-demo-prod
  namespace: kluctl-system
spec:
  interval: 10m
  source:
    url: https://github.com/kluctl/kluctl-examples.git
    path: "./microservices-demo/3-templating-and-multi-env/"
  timeout: 2m
  target: prod
  context: default
  prune: true

2.1 - Metrics

2.1.1 - v1beta1 metrics

Prometheus Metrics

The controller exports several metrics in the OpenMetrics compatible format . They can be scraped by all sorts of monitoring solutions (e.g. Prometheus) or stored in a database. Because the controller is based on controller-runtime , all the default metrics as well as the following controller-specific custom metrics are exported:

• kluctldeployment_controller

2.1.1.1 - Metrics of the KluctlDeployment Controller

Exported Metrics References

2.2 - Specs

2.2.1 - v1beta1 specs

gitops.kluctl.io/v1beta1

This is the v1beta1 API specification for defining continuous delivery pipelines of Kluctl Deployments.

Specification

• KluctlDeployment CRD
  • Spec fields
  • Reconciliation
  • Kubeconfigs and RBAC
  • Git authentication
  • Helm Repository authentication
  • Secrets Decryption
  • Status

2.2.1.1 - KluctlDeployment

The KluctlDeployment API defines a deployment of a target from a Kluctl Project .

Example

apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: microservices-demo-prod
spec:
  interval: 5m
  source:
    url: https://github.com/kluctl/kluctl-examples.git
    path: "./microservices-demo/3-templating-and-multi-env/"
  timeout: 2m
  target: prod
  context: default
  prune: true
  delete: true
  manual: true

In the above example a KluctlDeployment is being created that defines the deployment based on the Kluctl project.

The deployment is performed every 5 minutes. It will deploy the prod target and then prune orphaned objects afterward.

When the KluctlDeployment gets deleted, delete: true will cause the controller to actually delete the target resources.

It uses the default context provided by the default service account and thus overrides the context specified in the target definition.

Spec fields

source

The KluctlDeployment spec.source specifies the source repository to be used. Example:

apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: example
spec:
  source:
    url: https://github.com/kluctl/kluctl-examples.git
    path: path/to/project
    credentials:
      - host: github.com
        pathPrefix: kluctl/
        secretRef:
          name: git-credentials
    ref:
      branch: my-branch
  ...

The url specifies the git clone url. It can either be a https or a git/ssh url. Git/Ssh url will require a secret to be provided with credentials.

The path specifies the sub-directory where the Kluctl project is located.

The ref provides the Git reference to be used. It can either be a branch or a tag.

See Git authentication for details on authentication and the credentials field.

interval

See Reconciliation .

deployInterval

If set, the controller will periodically force a deployment, even if the rendered manifests have not changed. See Reconciliation for more details.

suspend

See Reconciliation .

target

spec.target specifies the target to be deployed. It must exist in the Kluctl projects kluctl.yaml targets list.

This field is optional and can be omitted if the referenced Kluctl project allows deployments without targets.

targetNameOverride

spec.targetNameOverride will set or override the name of the target. This is equivalent to passing --target-name-override to kluctl deploy.

context

spec.context will override the context used while deploying. This is equivalent to passing --context to kluctl deploy.

deployMode

By default, the operator will perform a full deployment, which is equivalent to using the kluctl deploy command. As an alternative, the controller can be instructed to only perform a kluctl poke-images command. Please see poke-images for details on the command. To do so, set spec.deployMode field to poke-images.

Example:

apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: microservices-demo-prod
spec:
  interval: 5m
  source:
    url: https://github.com/kluctl/kluctl-examples.git
    path: "./microservices-demo/3-templating-and-multi-env/"
  timeout: 2m
  target: prod
  context: default
  deployMode: poke-images

prune

To enable pruning, set spec.prune to true. This will cause the controller to run kluctl prune after each successful deployment.

delete

To enable deletion, set spec.delete to true. This will cause the controller to run kluctl delete when the KluctlDeployment gets deleted.

manual

spec.manual enables manually approved/triggered deployments. This means, that deployments are performed in dry-run mode until the most recent deployment is approved.

This feature is most useful in combination with the Kluctl Webui, which offers a visualisation and proper actions for this feature.

Internally, approval happens by setting spec.manualObjectsHash to the objects hash of the approved command result.

args

spec.args is an object representing arguments passed to the deployment. Example:

apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: example
spec:
  interval: 5m
  source:
    url: https://github.com/kluctl/kluctl-examples.git
    path: "./microservices-demo/3-templating-and-multi-env/"
  timeout: 2m
  target: prod
  context: default
  args:
    arg1: value1
    arg2: value2
    arg3:
      k1: v1
      k2: v2

The above example is equivalent to calling kluctl deploy -t prod -a arg1=value1 -a arg2=value2.

images

spec.images specifies a list of fixed images to be used by image.get_image(...) . Example:

apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: example
spec:
  interval: 5m
  source:
    url: https://example.com
  timeout: 2m
  target: prod
  images:
    - image: nginx
      resultImage: nginx:1.21.6
      namespace: example-namespace
      deployment: Deployment/example
    - image: registry.gitlab.com/my-org/my-repo/image
      resultImage: registry.gitlab.com/my-org/my-repo/image:1.2.3

The above example will cause the images.get_image("nginx") invocations of the example Deployment to return nginx:1.21.6. It will also cause all images.get_image("registry.gitlab.com/my-org/my-repo/image") invocations to return registry.gitlab.com/my-org/my-repo/image:1.2.3.

The fixed images provided here take precedence over the ones provided in the target definition .

spec.images is equivalent to calling kluctl deploy -t prod --fixed-image=nginx:example-namespace:Deployment/example=nginx:1.21.6 ... and to kluctl deploy -t prod --fixed-images-file=fixed-images.yaml with fixed-images.yaml containing:

images:
- image: nginx
  resultImage: nginx:1.21.6
  namespace: example-namespace
  deployment: Deployment/example
- image: registry.gitlab.com/my-org/my-repo/image
  resultImage: registry.gitlab.com/my-org/my-repo/image:1.2.3

dryRun

spec.dryRun is a boolean value that turns the deployment into a dry-run deployment. This is equivalent to calling kluctl deploy -t prod --dry-run.

noWait

spec.noWait is a boolean value that disables all internal waiting (hooks and readiness). This is equivalent to calling kluctl deploy -t prod --no-wait.

forceApply

spec.forceApply is a boolean value that causes kluctl to solve conflicts via force apply. This is equivalent to calling kluctl deploy -t prod --force-apply.

replaceOnError and forceReplaceOnError

spec.replaceOnError and spec.forceReplaceOnError are both boolean values that cause kluctl to perform a replace after a failed apply. forceReplaceOnError goes a step further and deletes and recreates the object in question. These are equivalent to calling kluctl deploy -t prod --replace-on-error and kluctl deploy -t prod --force-replace-on-error.

abortOnError

spec.abortOnError is a boolean value that causes kluctl to abort as fast as possible in case of errors. This is equivalent to calling kluctl deploy -t prod --abort-on-error.

includeTags, excludeTags, includeDeploymentDirs and excludeDeploymentDirs

spec.includeTags and spec.excludeTags are lists of tags to be used in inclusion/exclusion logic while deploying. These are equivalent to calling kluctl deploy -t prod --include-tag <tag1> and kluctl deploy -t prod --exclude-tag <tag2>.

spec.includeDeploymentDirs and spec.excludeDeploymentDirs are lists of relative deployment directories to be used in inclusion/exclusion logic while deploying. These are equivalent to calling kluctl deploy -t prod --include-tag <tag1> and kluctl deploy -t prod --exclude-tag <tag2>.

Reconciliation

The KluctlDeployment spec.interval tells the controller at which interval to try reconciliations. The interval time units are s, m and h e.g. interval: 5m, the minimum value should be over 60 seconds.

At each reconciliation run, the controller will check if any rendered objects have been changes since the last deployment and then perform a new deployment if changes are detected. Changes are tracked via a hash consisting of all rendered objects.

To enforce periodic full deployments even if nothing has changed, spec.deployInterval can be used to specify an interval at which forced deployments must be performed by the controller.

The KluctlDeployment reconciliation can be suspended by setting spec.suspend to true.

The controller can be told to reconcile the KluctlDeployment outside of the specified interval by annotating the KluctlDeployment object with kluctl.io/request-reconcile.

On-demand reconciliation example:

kubectl annotate --overwrite kluctldeployment/microservices-demo-prod kluctl.io/request-reconcile="$(date +%s)"

Similarly, a deployment can be forced even if the source has not changed by using the kluctl.io/request-deploy annotation:

kubectl annotate --overwrite kluctldeployment/microservices-demo-prod kluctl.io/request-deploy="$(date +%s)"

Kubeconfigs and RBAC

As Kluctl is meant to be a CLI-first tool, it expects a kubeconfig to be present while deployments are performed. The controller will generate such kubeconfigs on-the-fly before performing the actual deployment.

The kubeconfig can be generated from 3 different sources:

1. The default impersonation service account specified at controller startup (via --default-service-account)
2. The service account specified via spec.serviceAccountName in the KluctlDeployment
3. The secret specified via spec.kubeConfig in the KluctlDeployment.

The behavior/functionality of 1. and 2. is comparable to how the kustomize-controller handles impersonation, with the difference that a kubeconfig with a “default” context is created in-between.

spec.kubeConfig will simply load the kubeconfig from data.value of the specified secret.

Kluctl targets specify a context name that is expected to be present in the kubeconfig while deploying. As the context found in the generated kubeconfig does not necessarily have the correct name, spec.context can be used to while deploying. This is especially useful when using service account based kubeconfigs, as these always have the same context with the name “default”.

Here is an example of a deployment that uses the service account “prod-service-account” and overrides the context appropriately (assuming the Kluctl cluster config for the given target expects a “prod” context):

apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: example
  namespace: kluctl-system
spec:
  interval: 10m
  source:
    url: https://github.com/kluctl/kluctl-examples.git
    path: "./microservices-demo/3-templating-and-multi-env/"
  target: prod
  serviceAccountName: prod-service-account
  context: default

Git authentication

The spec.source can optionally specify spec.source.credentials (see here ), which lists multiple sets of credentials for different git hosts.

Each time the controller needs to access a git repository, it will iterate through this list and pick the first one matching.

Each credentials entry has the following fields:

host is required and specifies the hostname to apply this set of credentials. It can also be set to *, meaning that it will match all git hosts. * will however be ignored for https based urls to avoid leaking credentials.

pathPrefix is optional and allows to filter for different path prefixed on the same host. This is for example useful when public Git providers are used, for example github.com. For these, you can for example use my-org/ as prefix to tell the controller that it should use this set of credentials only for projects below the my-org GitHub organisation.

secretRef is required and specifies the name of the secret that contains the actual credentials.

The following authentication types are supported through the referenced secret.

Basic access authentication

To authenticate towards a Git repository over HTTPS using basic access authentication (in other words: using a username and password), the referenced Secret is expected to contain .data.username and .data.password values.

---
apiVersion: v1
kind: Secret
metadata:
  name: basic-access-auth
type: Opaque
data:
  username: <BASE64>
  password: <BASE64>

HTTPS Certificate Authority

To provide a Certificate Authority to trust while connecting with a Git repository over HTTPS, the referenced Secret can contain a .data.caFile value.

---
apiVersion: v1
kind: Secret
metadata:
  name: https-ca-credentials
  namespace: default
type: Opaque
data:
  caFile: <BASE64>

SSH authentication

To authenticate towards a Git repository over SSH, the referenced Secret is expected to contain identity and known_hosts fields. With the respective private key of the SSH key pair, and the host keys of the Git repository.

---
apiVersion: v1
kind: Secret
metadata:
  name: ssh-credentials
type: Opaque
stringData:
  identity: |
    -----BEGIN OPENSSH PRIVATE KEY-----
    ...
    -----END OPENSSH PRIVATE KEY-----    
  known_hosts: |
        github.com ecdsa-sha2-nistp256 AAAA...

Helm Repository authentication

Kluctl allows to integrate Helm Charts in two different ways. One is to pre-pull charts and put them into version control, making it unnecessary to pull them at deploy time. This option also means that you don’t have to take any special care on the controller side.

The other way is to let Kluctl pull Helm Charts at deploy time. In that case, you have to ensure that the controller has the necessary access to the Helm repositories. To add credentials for authentication, set the spec.helmCredentials field to a list of secret references:

Basic access authentication

apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: example
  namespace: kluctl-system
spec:
  interval: 10m
  source:
    url: https://github.com/kluctl/kluctl-examples.git
    path: "./microservices-demo/3-templating-and-multi-env/"
  target: prod
  serviceAccountName: prod-service-account
  context: default

  helmCredentials:
    - secretRef:
        name: helm-creds
---
apiVersion: v1
kind: Secret
metadata:
  name: helm-creds
  namespace: kluctl-system
stringData:
  url: https://example-repo.com
  username: my-user
  password: my-password

TLS authentication

For TLS authentication, see the following example secret:

apiVersion: v1
kind: Secret
metadata:
  name: helm-creds
  namespace: kluctl-system
data:
  certFile: <BASE64>
  keyFile: <BASE64>
  # NOTE: Can be supplied without the above values
  caFile: <BASE64>

Disabling TLS verification

In case you need to disable TLS verification (not recommended!), add the key insecureSkipTlsVerify with the value "true" (make sure it’s a string, so surround it with ").

Pass credentials

To enable passing of credentials to all requests, add the key passCredentialsAll with the value "true". This will pass the credentials to all requests, even if the hostname changes.

Secrets Decryption

Kluctl offers a SOPS Integration that allows to use encrypted manifests and variable sources in Kluctl deployments. Decryption by the controller is also supported and currently mirrors how the Secrets Decryption configuration of the Flux Kustomize Controller. To configure it in the KluctlDeployment, simply set the decryption field in the spec:

apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: example
  namespace: kluctl-system
spec:
  decryption:
    provider: sops
    secretRef:
      name: sops-keys
  ...

The sops-keys Secret has the same format as in the Flux Kustomize Controller .

AWS KMS with IRSA

In addition to the AWS KMS Secret Entry in the secret and the global AWS KMS authentication via the controller’s service account, the Kluctl controller also supports using the IRSA role of the impersonated service account of the KluctlDeployment (specified via serviceAccountName in the spec or --default-service-account):

apiVersion: v1
kind: ServiceAccount
metadata:
  name: kluctl-deployment
  namespace: kluctl-system
  annotations:
    eks.amazonaws.com/role-arn: arn:aws:iam::123456:role/my-irsa-enabled-role
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
  name: kluctl-deployment
  namespace: kluctl-system
roleRef:
  apiGroup: rbac.authorization.k8s.io
  kind: ClusterRole
  # watch out, don't use cluster-admin if you don't trust the deployment
  name: cluster-admin
subjects:
  - kind: ServiceAccount
    name: kluctl-deployment
    namespace: kluctl-system
---
apiVersion: gitops.kluctl.io/v1beta1
kind: KluctlDeployment
metadata:
  name: example
  namespace: kluctl-system
spec:
  serviceAccountName: kluctl-deployment
  decryption:
    provider: sops
    # you can also leave out the secretRef if you don't provide addinional keys
    secretRef:
      name: sops-keys
  ...

Status

When the controller completes a deployments, it reports the result in the status sub-resource.

A successful reconciliation sets the ready condition to true.

status:
  conditions:
  - lastTransitionTime: "2022-07-07T11:48:14Z"
    message: "deploy: ok"
    reason: ReconciliationSucceeded
    status: "True"
    type: Ready
  lastDeployResult:
    ...
  lastPruneResult:
    ...
  lastValidateResult:
    ...

You can wait for the controller to complete a reconciliation with:

kubectl wait kluctldeployment/backend --for=condition=ready

A failed reconciliation sets the ready condition to false:

status:
  conditions:
  - lastTransitionTime: "2022-05-04T10:18:11Z"
    message: target invalid-name not found in kluctl project
    reason: PrepareFailed
    status: "False"
    type: Ready
  lastDeployResult:
    ...
  lastPruneResult:
    ...
  lastValidateResult:
    ...

Note that the lastDeployResult, lastPruneResult and lastValidateResult are only updated on a successful reconciliation.

2.3 - Installation

The controller can be installed via two available options.

Using the “install” sub-command

The kluctl controller install command can be used to install the controller. It will use an embedded version of the Controller Kluctl deployment project found here .

Using a Kluctl deployment

To manage and install the controller via Kluctl, you can use a Git include in your own deployment:

deployments:
  - git:
      url: https://github.com/kluctl/kluctl.git
      subDir: install/controller
      ref:
        tag: v2.21.2

2.4 - Legacy Controller Migration

Older versions of Kluctl (pre v2.20.0) relied on a legacy version of the Kluctl controller, named flux-kluctl-controller . If you upgraded from such an older version and were already using KluctlDeployments from the flux.kluctl.io API group, you must migrate these deployments to the new gitops.kluctl.io group.

To do this, follow the following steps:

1. Upgrade the legacy flux-kluctl-controller to at least v0.16.0. This version will introduce a special marker field into the legacy KluctlDeployment status and set it to true. This marker field is used to inform the new Kluctl Controller that the legacy controller is now aware of the existence of the new controller.
2. If not already done, install the new Kluctl Controller.
3. To be on the safe side, disable pruning and deletion for all legacy KluctlDeployment objects. Don’t forget to deploy/apply these changes before continuing with the next step.
4. Modify your KluctlDeployment manifests to use the gitops.kluctl.io/v1beta1 as apiVersion. It’s important to use the same name and namespace as used in the legacy resources. Also read the breaking changes section.
5. Deploy/Apply the modified KluctlDeployment resources.
6. At this point, the legacy controller will detect that the KluctlDeployment exists twice, once for the legacy API group/version and once for the new group/version. Based on that knowledge, the legacy controller will stop reconciling the legacy KluctlDeployment.
7. At the same time, the new controller will detect that the legacy KluctlDeployment has the marker field set, which means that the legacy controller is known to honor the new controller’s existence.
8. This will lead to the new controller taking over and reconciling the new KluctlDeployment.
9. If you disabled deletion/pruning in step 3., you should undo this on the new KluctlDeployments now.

After these steps, the legacy KluctlDeployment resources will be excluded from reconciliation by the legacy controller. This means, you can safely remove/prune the legacy resources.

Breaking changes

There exist some breaking changes between the legacy flux.kluctl.io/v1alpha1 and gitops.kluctl.io/v1beta1 custom resources and controllers. These are:

Only deploy when resources change

The legacy controller did a full deploy on each reconciliation, following the Flux way of reconciliations. This behaviour was configurable by allowing you to set spec.deployInterval: never, which disabled full deployments and caused the controller to only deploy when the resulting rendered resources actually changed.

The new controller will behave this way by default, unless you explicitly set spec.deployInterval to some interval value.

This means, you will have to introduce spec.deployInterval in case you expect the controller to behave as before or remove spec.deployInterval: never if you already used the Kluctl specific behavior.

renameContexts has been removed

The spec.renameContexts field is not available anymore. Use spec.context instead.

status will not contain full result anymore

The legacy controller wrote the full command result (with objects, diffs, …) into the status field. The new controller will instead only write a summary of the result.

Why no fully automated migration?

I have decided against a fully automated migration as the move of the API group causes resources to have a different identity. This can easily lead to unexpected behaviour and does not play well with GitOps.

2.5 - Kluctl Controller API reference

Packages:

• gitops.kluctl.io/v1beta1

gitops.kluctl.io/v1beta1

Package v1beta1 contains API Schema definitions for the gitops.kluctl.io v1beta1 API group.

Decryption

(Appears on: KluctlDeploymentSpec)

Decryption defines how decryption is handled for Kubernetes manifests.

GitCredentials

(Appears on: ProjectSource)

HelmCredentials

(Appears on: KluctlDeploymentSpec)

KluctlDeployment

KluctlDeployment is the Schema for the kluctldeployments API

KluctlDeploymentSpec

(Appears on: KluctlDeployment)

KluctlDeploymentStatus

(Appears on: KluctlDeployment)

KluctlDeploymentStatus defines the observed state of KluctlDeployment

KubeConfig

(Appears on: KluctlDeploymentSpec)

KubeConfig references a Kubernetes secret that contains a kubeconfig file.

LocalObjectReference

(Appears on: Decryption, GitCredentials, HelmCredentials, ProjectSource)

ProjectSource

(Appears on: KluctlDeploymentSpec)

SafeDuration

(Appears on: KluctlDeploymentSpec)

SecretKeyReference

(Appears on: KubeConfig)

SecretKeyReference contains enough information to locate the referenced Kubernetes Secret object in the same namespace. Optionally a key can be specified. Use this type instead of core/v1 SecretKeySelector when the Key is optional and the Optional field is not applicable.

3 - Kluctl Webui

The Kluctl Webui is a powerful UI which allows you to monitor and control your Kluctl GitOps deployments.

You can run it locally or install it to your Kubernetes cluster.

State of the Webui

Please note that the Kluctl Webui is still in early stage of development, missing many planned features. It might also contain bugs and be unstable in some situations. If you encounter any such problems, please report these to https://github.com/kluctl/kluctl/issues .

Screenshots

Targets Overview

Command Result

3.1 - Installation

The Kluctl Webui can be installed by using a Git Include that refers to the webui deployment project . Example: