GitHub Actions Workflow Syntax: Jobs with Examples

GitHub Actions offer a platform to automate, customize, and execute your software development workflows right in your repository. In this blog post, we’ll explore the syntax of GitHub Actions’ workflow, focusing on the ‘jobs’ attribute. We’ll explain its usage and provide some practical examples to illustrate the concept.

Introduction

GitHub Actions Workflow allows you to build, test, and deploy your code directly from GitHub. It’s essentially a CI/CD (Continuous Integration and Continuous Delivery) platform that facilitates automatic building and testing of your code.

A Workflow is an automated process that you set up in your repository to build, test, package, release, or deploy any project on GitHub. These Workflows are composed of one or more ‘jobs’ which are a series of ‘steps’ that execute commands (actions).

Understanding the ‘Jobs’ Syntax

Every GitHub Actions Workflow is defined in a YAML file called a Workflow file. This file is stored in the ‘.github/workflows’ directory of your repository. Within this file, the ‘jobs’ attribute is used to define a sequence of tasks that run in parallel or sequentially.

Each job runs on a fresh instance of the virtual environment specified by ‘runs-on’. Therefore, each job in a workflow is isolated and does not share a common state with other jobs.

The syntax for defining ‘jobs’ in your workflow file is as follows:

jobs:
  job_id:
    name: job_name
    runs-on: runner_type
    steps:
    - name: Step 1
      uses: action_1
    - name: Step 2
      uses: action_2

jobs:

job_id:

runs-on: runner_type

steps:

- name: Step 1

uses: action_1

- name: Step 2

uses: action_2

‘job_id’ is a unique identifier for the job and is required.
‘job_name’ is an optional attribute to specify a descriptive name for the job.
‘runner_type’ is the type of machine to run the job on. It can be a GitHub-hosted runner or a self-hosted runner.
‘steps’ is a sequence of tasks that will be executed in the job.

Example of ‘Jobs’ in a Workflow

Let’s consider an example of a simple GitHub Actions Workflow to understand ‘jobs’ better. This workflow checks out your repository and prints “Hello World!” to the console.

name: Hello World Workflow

on: [push]

jobs:
  build:
    name: Print Message
    runs-on: ubuntu-latest
    steps:
    - name: Checkout code
      uses: actions/checkout@v2
    - name: Hello World step
      run: echo "Hello, World!"

on: [push]

jobs:

build:

runs-on: ubuntu-latest

steps:

- name: Checkout code

uses: actions/checkout@v2

- name: Hello World step

run: echo "Hello, World!"

In the ‘jobs’ section, we have a single job identified as ‘build’. This job is named “Print Message” and runs on the latest version of Ubuntu. The job includes two steps: checking out the repository’s code and running the ‘echo’ command to print “Hello, World!” to the console.

Conclusion

Understanding ‘jobs’ in GitHub Actions Workflow syntax is crucial to automate your software development processes. ‘Jobs’ are the building blocks of a workflow, defining a series of tasks to be executed in order. By understanding the structure and usage of ‘jobs’, you can effectively utilize GitHub Actions to establish robust CI/CD pipelines.