Render Template

GitHub Action to render file based on template and passed variables.

[!NOTE]
This is a Docker-based action and may not work on Windows and MacOS runners.

Inputs

You must set at least vars or vars_path.
You may set both of them (vars values will precede over vars_path).

Variables names must be alphanumeric strings (must not contain any hyphens).

There are few template functions available:

• date – formats timestamp using Go's time layout.
  Example: {{ "2023-05-11T01:42:04Z" | date "2006-01-02" }} will be rendered as 2023-05-11.
  You may use timezone input to set timezone for date function (e.g. timezone: "America/New_York").

• mdlink – creates markdown link.
  Example: {{ "https://github.com" | mdlink "GitHub" }} will be rendered as [GitHub](https://github.com).

• number – formats number in English locale.
  Example: {{ 1234567890 | number }} will be rendered as 1,234,567,890.

• base64 – encodes string to base64.
  Example: {{ "hello" | base64 }} will be rendered as aGVsbG8=.

• split – splits string by delimiter.

• toJSON – converts string to JSON.
  Example: {{ "1,2,3" | split "," | toJSON }} will be rendered as ["1","2","3"].

Outputs

Example

kube.template.yml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ .deployment }}
  labels:
    app: {{ .app }}
spec:
  replicas: 3
  selector:
    matchLabels:
      app: {{ .app }}
  template:
    metadata:
      labels:
        app: {{ .app }}
    spec:
      containers:
      - name: {{ .app }}
        image: {{ .image }}
        ports:
        - containerPort: 80

.github/workflows/main.yml

name: main
on:
  push:
    branches:
      - main
env:
  DOCKER_IMAGE: username/image
  DEPLOYMENT_NAME: nginx-deployment
jobs:
  main:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v3

      <...>

      - name: Render template
        id: render_template
        uses: chuhlomin/render-template@v1
        with:
          template: kube.template.yml
          vars: |
            image: ${{ env.DOCKER_IMAGE }}:${{ github.sha }}
            deployment: ${{ env.DEPLOYMENT_NAME }}
            app: nginx

      - name: Deploy
        timeout-minutes: 4
        run: |-
          echo '${{ steps.render_template.outputs.result }}' | kubectl apply -f -
          kubectl rollout status deployment/$DEPLOYMENT_NAME