Kubectl for PowerShell

🚧 Work in progress 🚧

kubectl implemented as PowerShell Cmdlets, giving you native PowerShell object output, tab completion and error handling - while mirroring the default output formatting of kubectl.

Runs in PowerShell Core on macOS, Linux and Windows. Note: Windows PowerShell v5 is not supported. If you are on Windows, you need to install PowerShell Core. You must use PowerShell Core v6.1.0 or newer.

Features

App Management

Get-KubeResource

Equivalent to kubectl get and kubectl describe. Just like with those, the first parameter is the kind of resource to get. The default output formatting mirrors the tabular output of kubectl get, but you can get all Pod properties from the returned objects. The Name parameter supports wildcard patterns, which can be very convenient to get all pods for a deployment (e.g. Get-KubePod my-deployment-*). It also supports tab-autocompletion. Pass the namespace with -Namespace.

There are also specialised cmdlets for common kinds like Get-KubePod and Get-KubeDeployment. They work the same way, but without Kind parameter.

Get-KubeLog

Equivalent to kubectl logs. Pass -Follow to stream logs. The cmdlet accepts pipeline input from Get-KubePod.

Publish-KubeResource

Equivalent to kubectl apply. Takes Kubernetes objects or YAML file paths as pipeline or parameter input and sends them to the server to apply the difference. Supports -WhatIf and -Confirm. Prints the updated object returned by the server.

Important: This uses a new beta feature of Kubernetes, server-side apply, which needs to be enabled on the server. This is safer and avoids reverse-engineering the client-side apply algorithm used currently by kubectl. Soon, kubectl will also do server-side applys by default. While the feature is in beta, you need to start the Kubernetes server with --feature-gates=ServerSideApply=true.

In opposite to client-side apply, server-side apply will fail with a conflict error if any of touched the fields were updated before by a different field manager, or overridden with a client-side apply or edit. Pass -Force to resolve the conflict in these cases.

Example:

Publish-KubeResource *.yml
Get-ChildItem *.yml -Recurse | Publish-KubeResource

Editing a field before updating:

Get-ChildItem *.Deployment.yml -Recurse |
    Get-Content -Raw |
    ConvertFrom-KubeYaml |
    ForEach-Object { $_.Spec.Template.Spec.Containers[0].Image = $newImage; $_ } |
    Publish-KubeResource

Remove-KubeResource

Removes a Kubernetes resource. Equivalent to kubectl delete. Accepts pipeline input from Get- cmdlets, parsed YAML, kubectl JSON and PSCustomObjects.

Serialization

ConvertFrom-KubeYaml

Takes YAML strings as pipeline input, parses it and returns Kubernetes objects. The objects are PSObjects with only the properties from the YAML set (important for diffing purposes), but will have the correct type names set for pretty output formatting. Other cmdlets take these objects as input.

ConvertTo-KubeYaml

Takes the output of Get-KubeResource, ConvertFrom-KubeYaml or PSCustomObjects and serializes them to valid Kubernetes YAML. This can be used to persist a change to a resource back to disk, or to pipe it to native kubectl.

Example:

Get-Content -Raw some.Deployment.yml |
    ConvertFrom-KubeYaml |
    ForEach-Object { $_.Spec.Template.Spec.Containers[0].Image = $newImage; $_ } |
    ConvertTo-KubeYaml |
    Out-File some.Deployment.yml

Configuration

Get-KubeConfig

Gets the Kubernetes configuration parsed from ~/.kube/config.

To get the clusters like kubectl config get-clusters, run (Get-KubeConfig).Clusters. To get all contexts like kubectl config get-contexts, run (Get-KubeConfig).Contexts. To get the current context like kubectl config current-context, run (Get-KubeConfig).CurrentContext

Set-KubeConfig

Warning: This currently deletes unsupported auth configuration!

A convenience cmdlet to update kubeconfig. Does nothing but serialize a given config object back to YAML and save it back to ~/.kube/config.

Use-KubeContext

A convenience cmdlet to update the current context. Supports tab-completion for the context name. Equivalent of kubectl config use-context.

Authentication

PSKubectl reads authentication from your ~/.kube/config and includes support for command-based authentication as used by GKE.

Development

Run ./build.ps1 to build.

./load.ps1 will build and load the module into a new shell. Run exit and rerun ./load.ps1 to reload the module.

Tests

Tests are written in PowerShell with Pester and run against an actual test Kubernetes cluster, such as Minikube or Docker for Desktop. If you want to run them locally, make sure to set your kubectl context to a throw-away cluster. Then execute Invoke-Pester ./Tests to run the tests.