airshipctl/krm-functions/toolbox

Toolbox

This is KRM function written in go and uses the kyaml library for executing binaries inside container. It helps to run scripts in container as a airshipctl phase. The toolbox image has pre-installed sh shell,kubectl and calicoctl.

How to run your script as airshipctl phase

NOTE: All file paths in the following steps depend on the site you are working with and differ depending on the environment.

1. Create a phase document (kind: Phase)

    apiVersion: airshipit.org/v1alpha1
    kind: Phase
    metadata:
      name: kubectl-wait-node-ephemeral
      clusterName: ephemeral-cluster
    config:
      executorRef:
        apiVersion: airshipit.org/v1alpha1
        kind: GenericContainer
        name: kubectl-get-node
   

2. Create executor document (kind: GenericContainer). The executor use configRef to reference ConfigMap that will be generated using configMapGenerator. configRef must reference a Kubernetes ConfigMap with data key script with the script you want to execute. You can use kustomize configMapGenerator to create ConfigMaps (see example).

    apiVersion: airshipit.org/v1alpha1
    kind: GenericContainer
    metadata:
      name: kubectl-get-node
      labels:
        airshipit.org/deploy-k8s: "false"
    spec:
      type: krm
      image: quay.io/airshipit/toolbox:latest
      hostNetwork: true
      envVars
        MY_ENV # airshipctl will populate this value from your current env, you can pass credentials like this
        MY_ENV_TWO="my-value"
    configRef:
      kind: ConfigMap
      name: kubectl-get-node
      apiVersion: v1
   

3. Add your script as a ConfigMap. Scripts inside container have access to site kubeconfig in ${KUBECONFIG} and to context of the cluster in ${KCTL_CONTEXT} environment variables.

    apiVersion: v1
    kind: ConfigMap
    metadata:
      name: kubectl-get-node
    data:
      script: |
        #!/bin/sh
        calicoctl apply --context ${KTCL_CONTEXT} -f $RENDERED_BUNDLE_PATH
        kubectl apply --context ${KTCL_CONTEXT} -f $RENDERED_BUNDLE_PATH
   

   1. add kustomize resources
   2. include them into PhaseConfigBundle

4. Make sure it is added to the bundle:

   1. airshipctl phase render --source config -k ConfigMap find your configmap in the output
   2. airshipctl phase render --source config -k Phase find your phase in output
   3. airshipctl phase render --source config -k GenericContainer find your executor in output

5. Run your phase: airshipctl phase run kubectl-wait-node-ephemeral

Input bundle usage

The KRM function writes to filesystem input bundle specified in documentEntryPoint in phase declaration and imports the path to this bundle in RENDERED_BUNDLE_PATH environment variable. For example it can be used with calicoctl as calicoctl apply -f $RENDERED_BUNDLE_PATH

Important notes

The script must write to STDOUT valid yaml or redirect output to STDERR otherwise phase will fail with mapping values are not allowed in this context