Setting up GitHub Actions for automated tasks

GitHub Actions help in integrating CI/CD so you can test, build, deploy your code right from GitHub. In this post, we will set up a couple of workflows to run when a PR is raised to any branch.

List of workflows to setup:

automated testing
validate build status
validate Docker build status

A simple workflow

A workflow is very easy to understand. It has a name attribute, on attribute and a list of jobs to be performed when an event matches the on attributes.

name: <workflow name>

on:
    <conditions>

jobs:
    job1:
        ...
        steps:
            ...
    job2:
        ...
        steps:
            ...

We will get to know more about it when we'll set up an actual workflow.

1. setup automated testing

Like the simple workflow, we'll use the same structure here as well. Let's give it a name.

name: Test

The next step is when to trigger this workflow.

on:
  # Run tests for push event in master branch.
  push:
    branches: [master]

  # Run tests for any PRs.
  pull_request:

This will match with any PR raised against any branch and any push event against the master branch. The same branch filter can be added to the pull_request part to run the GitFlow for any PR against the master branch.

Now, let's set up the job to perform when the GitFlow is triggered.

jobs:
    test:
        runs-on: ubuntu-latest

        steps:
            - uses: actions/checkout@v2
            - name: Use Node.js to test
              uses: actions/setup-node@v1
              with:
                  node-version: "10.x"
            - run: npm i
            - run: npm test
              env:
                  CI: true

The above snippet has only one job listed i.e test.

The job needs a machine to run on, which is specified using runs-on label. Other available labels are windows-latest, macos-latest.

steps section has a list of statements to execute.

uses: actions/checkout@v2
check out the codebase: This action checks-out your repository, so your workflow can access it.
uses: actions/setup-node@v1
setup nodejs: Download and cache a version of node.js - npm by version specified (mentioned in with block).
run: npm i and run: npm test
run command: Runs command-line programs using the operating system's shell. The command can be of a single line or multi-line command.
- single-line command:
```
run: npm install
```
- multi-line command:
```
name: Clean install and build
run: |
  npm ci
  npm run build
```
  An optional name attribute can be used to display step name or it defaults to the text specified in the run command. Also, an environment variable CI needs to be set explicitly.

The final file looks like something this.

name: Test

on:
    # Run tests for push event in master branch.
    push:
        branches: [master]

    # Run tests for any PRs.
    pull_request:

jobs:
    test:
        runs-on: ubuntu-latest

        steps:
            - uses: actions/checkout@v2
            - name: Use Node.js to test
              uses: actions/setup-node@v1
              with:
                  node-version: "10.x"
            - run: npm i
            - run: npm test
              env:
                  CI: true

2. setup to validate build status

The GitFlow file to validate build status is the same as the test one. The only thing needs to be updated in the file is the run command.

name: Test

on:
    # Run tests for push event in master branch.
    push:
        branches: [master]

    # Run tests for any PRs.
    pull_request:

jobs:
    test:
        runs-on: ubuntu-latest

        steps:
            - uses: actions/checkout@v2
            - name: Use Node.js to test
              uses: actions/setup-node@v1
              with:
                  node-version: "10.x"
            - run: npm i
            # the command for building the package
            - run: npm run build
              env:
                  CI: true

3. setup to validate Docker build status

The GitFlow file to validate Docker build status is also the same as the test one. The only thing needs to be updated in the file is the run command.
If you have a docker-compose.test.yml or Dockerfile in the root directory, then it'll build the docker image. It will just build the image and not upload it to any container registry.

name: DockerBuildTest

on:
    push:
        # Publish `master` as Docker `latest` image.
        branches:
            - master
        # Publish `v1.2.3` tags as releases.
        tags:
            - v*
    # Run tests for any PRs.
    pull_request:

jobs:
    # Run tests.
    # See also https://docs.docker.com/docker-hub/builds/automated-testing/
    test:
        runs-on: ubuntu-latest

        steps:
            - uses: actions/checkout@v2
            - name: Run tests
              run: |
                  if [ -f docker-compose.test.yml ]; then
                    docker-compose --file docker-compose.test.yml build
                    docker-compose --file docker-compose.test.yml run sut
                  else
                    docker build . --file Dockerfile
                  fi

What's next

The same .yml file can be updated to upload to a registry with a successful test job. The status of the task can be displayed as a badge. Open the action tab of the repository, and select a workflow and click on the Copy status badge Markdown button and add to the README.md file.

Binod Swain's Blog