GitHub Actions Workflows

Reusable GitHub Actions workflows for automatic builds and deployments with Railpack

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Browse the reusable GitHub Actions workflows repository

CNAP provides reusable GitHub Actions workflows that automatically build Docker images from your source code using Railpack and notify CNAP when new images are ready.

Already have a build pipeline? You can use individual reusable actions (like notify-cnap) to integrate CNAP notifications into your existing workflows. See Using Individual Actions → for details.

What It Does

The CNAP GitHub Actions workflows automate the entire build and deployment pipeline:

1. Checkout code - Retrieves your repository code
2. Language detection - Railpack automatically detects your language and framework
3. Build configuration - Automatically configures build and runtime settings
4. Image building - Builds a production-ready Docker image using Railpack
5. Registry push - Pushes the image to GitHub Container Registry (GHCR)
6. CNAP notification - Automatically notifies CNAP about the new image

This means you can push code to GitHub and have containerized applications ready to deploy in CNAP without writing Dockerfiles or managing build pipelines.

Quick Start

Add the workflow to your repository with zero configuration:

name: CNAP Build & Deploy
on:
  push:
    branches: [main]
  workflow_dispatch:

jobs:
  cnap:
    uses: cnap-tech/actions/.github/workflows/cnap.yml@main
    permissions:
      contents: read
      packages: write
      id-token: write
    secrets: inherit

This workflow automatically:

• Detects your application’s language and framework
• Builds a Docker image using Railpack
• Pushes to ghcr.io/your-username/your-repo:sha-<commit-sha>
• Notifies CNAP about the new build

Configuration Options

You can customize the workflow behavior with optional inputs:

build-context · string · default: "./"

Directory containing your application code. Use this for monorepos or projects with multiple applications.

build-command · string

Override Railpack’s automatically detected build command. If not specified, Railpack analyzes your code to determine the build command.

start-command · string

Override Railpack’s automatically detected start command. If not specified, Railpack analyzes your code to determine the start command.

build-apt-packages · string

Space-separated list of additional apt packages needed during the build phase (e.g., python3-dev libpq-dev).

runtime-apt-packages · string

Space-separated list of additional apt packages needed at runtime (e.g., postgresql-client curl).

Custom Build Context

For monorepos or projects with multiple applications:

jobs:
  deploy-api:
    uses: cnap-tech/actions/.github/workflows/cnap.yml@main
    permissions:
      contents: read
      packages: write
      id-token: write
    secrets: inherit
    with:
      build-context: './apps/api'

  deploy-web:
    uses: cnap-tech/actions/.github/workflows/cnap.yml@main
    permissions:
      contents: read
      packages: write
      id-token: write
    secrets: inherit
    with:
      build-context: './apps/web'

Custom Dependencies

Add system packages for build or runtime:

jobs:
  cnap:
    uses: cnap-tech/actions/.github/workflows/cnap.yml@main
    permissions:
      contents: read
      packages: write
      id-token: write
    secrets: inherit
    with:
      build-apt-packages: 'python3-dev libpq-dev'
      runtime-apt-packages: 'postgresql-client'

Supported Languages

Railpack supports 10+ languages and frameworks with automatic detection:

• Node.js - Express, Next.js, SvelteKit, Remix, Nuxt
• Python - Django, FastAPI, Flask
• Go - Gin, Echo, Chi
• PHP - Laravel, Symfony
• Java - Spring Boot, Quarkus
• Ruby - Rails, Sinatra
• Rust - Actix, Rocket, Axum
• Deno - Web frameworks
• Elixir - Phoenix
• Static files - HTML, CSS, JavaScript
• Shell scripts - Bash applications

See the Railpack documentation for complete language support and configuration options.

How It Works with CNAP

When you connect a GitHub repository to CNAP and the workflow runs:

1. Workflow builds image - The GitHub Actions workflow builds your application using Railpack
2. Image pushed to GHCR - The built image is pushed to GitHub Container Registry
3. CNAP notified - The workflow automatically notifies CNAP about the new build
4. Build appears in CNAP - The build shows up in your product’s build history
5. Ready to deploy - You can select the new build when creating or updating installations

The workflow uses OIDC authentication to securely notify CNAP without requiring API keys or secrets. The id-token: write permission enables this secure authentication method.

Integration with CNAP Products

When you create a product in CNAP using a GitHub repository source:

1. Repository connected - CNAP connects to your GitHub repository via GitHub App
2. Builds detected - CNAP automatically detects builds from the workflow
3. Images available - Built images appear in the build selection interface
4. Automatic updates - New builds automatically appear when the workflow runs

You don’t need to manually configure the workflow—CNAP handles the integration automatically when you connect a GitHub repository.

Using Individual Actions

The reusable workflow is composed of individual reusable actions that you can use independently in your existing pipelines. This is useful when you already have a build process and just need to notify CNAP about new images.

Notify CNAP After Existing Build

If you already have a workflow that builds Docker images, you can use the notify-cnap action to notify CNAP at the end of your pipeline:

name: Build and Deploy

on:
  push:
    branches: [main]

jobs:
  build:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
      id-token: write
    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Build Docker image
        run: |
          docker build -t ghcr.io/${{ github.repository }}:${{ github.sha }} .
          docker push ghcr.io/${{ github.repository }}:${{ github.sha }}

      - name: Notify CNAP
        uses: cnap-tech/actions/.github/actions/notify-cnap@main
        with:
          image: ghcr.io/${{ github.repository }}:${{ github.sha }}
          image-tag: ${{ github.sha }}

notify-cnap Action Parameters

image · string · required

Full Docker image name including registry and tag (e.g., ghcr.io/owner/repo:sha-abc123).

image-tag · string · required

Image tag, usually the commit SHA. This is used by CNAP to identify the specific build.

notify-url · string · default: "https://cnap.tech/api/github/build-notify"

CNAP API URL for build notifications. Only change this if you’re using a custom CNAP instance.

Available Actions

The repository provides these reusable actions:

Action	Description	Use Case
notify-cnap	Sends build notification to CNAP API	Use at the end of any pipeline that builds Docker images
build-railpack	Builds a Docker image using Railpack	Use when you want Railpack builds but need custom workflow steps
setup-buildkit	Starts a BuildKit container	Use when you need BuildKit for custom builds
stop-buildkit	Stops the BuildKit container	Use to clean up BuildKit after builds
generate-railpack-config	Generates Railpack configuration file	Use when you need custom Railpack config

Using Build-Railpack Action

If you want to use Railpack for building but need more control over your workflow:

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v4

      - name: Install Railpack
        run: curl -sSL https://railpack.com/install.sh | bash

      - name: Setup BuildKit
        uses: cnap-tech/actions/.github/actions/setup-buildkit@main

      - name: Build with Railpack
        uses: cnap-tech/actions/.github/actions/build-railpack@main
        with:
          image-name: ghcr.io/${{ github.repository }}:${{ github.sha }}
          build-context: './src'

      - name: Push image
        run: docker push ghcr.io/${{ github.repository }}:${{ github.sha }}

      - name: Notify CNAP
        uses: cnap-tech/actions/.github/actions/notify-cnap@main
        with:
          image: ghcr.io/${{ github.repository }}:${{ github.sha }}
          image-tag: ${{ github.sha }}

build-railpack Action Parameters

image-name · string · required

Full Docker image name including registry and tag (e.g., ghcr.io/owner/repo:sha-abc123).

build-context · string · default: "./"

Directory containing application code. Use this for monorepos or projects with multiple applications.

build-command · string

Override Railpack’s automatically detected build command. If not specified, Railpack analyzes your code to determine the build command.

start-command · string

Override Railpack’s automatically detected start command. If not specified, Railpack analyzes your code to determine the start command.

Advanced Usage

Custom Build Commands

Override Railpack’s automatic detection:

with:
  build-command: 'npm run build:production'
  start-command: 'node server.js'

Multiple Environments

Deploy different branches to different environments:

on:
  push:
    branches: [main, staging]

jobs:
  cnap:
    uses: cnap-tech/actions/.github/workflows/cnap.yml@main
    permissions:
      contents: read
      packages: write
      id-token: write
    secrets: inherit
    with:
      build-context: ${{ github.ref == 'refs/heads/main' && './apps/prod' || './apps/staging' }}

Related Topics

• GitHub Integration → - Learn how to connect GitHub repositories to CNAP
• Application Sources → - Understand GitHub repository sources
• Generic App Chart → - See how GitHub deployments use the generic chart
• Create a Product → - Create products from GitHub repositories