cm2kc (clustermap to kubeconfig)

Description

cm2kc is a CLI tool used to convert a clustermap file to a kubeconfig file.

Usage

go run ./cmd/cm2kc <options>

The following is a list of supported options for cm2kc:

  -i, --input string    Input clustermap file. (default "/dev/stdin")
  -o, --output string   Output kubeconfig file. (default "/dev/stdout")

Examples

Add a kubeconfig file in a secret: kubeconfig from a clustermap file in another secret: build-cluster for context: my-context

The following command will:

  1. Get a clustermap formatted secret: build-cluster in key: cluster for context: my-context.
  2. Base64 decode the secret.
  3. Convert the clustermap data to a kubeconfig format.
  4. Create a kubeconfig formatted secret: kubeconfig in key: config for context: my-context from the converted data.
kubectl --context=my-context get secrets build-cluster -o jsonpath='{.data.cluster}' |
  base64 -d |
  go run ./cmd/cm2kc |
  kubectl --context=my-context create secret generic kubeconfig --from-file=config=/dev/stdin

Lastly, to begin using this in Prow, update the volume mount and replace --build-cluster with --kubeconfig in the deployment of each relevant Prow component (e.g. crier, deck, plank, and sinker).

Create a kubeconfig file at path /path/to/kubeconfig.yaml from a clustermap file at path /path/to/clustermap.yaml

Ensure the clustermap file exists at the specified --input path:

# /path/to/clustermap.yaml

default:
  clientCertificate: fake-default-client-cert
  clientKey: fake-default-client-key
  clusterCaCertificate: fake-default-ca-cert
  endpoint: https://1.2.3.4
build:
  clientCertificate: fake-build-client-cert
  clientKey: fake-build-client-key
  clusterCaCertificate: fake-build-ca-cert
  endpoint: https://5.6.7.8

Execute cm2kc specifying an --input path to the clustermap file and an --output path to the desired location of the generated kubeconfig file:

go run ./cmd/cm2kc --input=/path/to/clustermap.yaml --output=/path/to/kubeconfig.yaml

The following kubeconfig file will be created at the specified --output path:

# /path/to/kubeconfig.yaml

apiVersion: v1
clusters:
- name: default
  cluster:
    certificate-authority-data: fake-default-ca-cert
    server: https://1.2.3.4
- name: build
  cluster:
    certificate-authority-data: fake-build-ca-cert
    server: https://5.6.7.8
contexts:
- name: default
  context:
    cluster: default
    user: default
- name: build
  context:
    cluster: build
    user: build
current-context: default
kind: Config
preferences: {}
users:
- name: default
  user:
    client-certificate-data: fake-default-ca-cert
    client-key-data: fake-default-ca-cert
- name: build
  user:
    client-certificate-data: fake-build-ca-cert
    client-key-data: fake-build-ca-cert

Last modified April 19, 2024: doc: Update cmd & pkg paths (follow-up of #101) (c3d3f01eb)