Automate Your Workflow with GitHub Actions

One of GitHub's most powerful features is GitHub Actions, which lets you automate software workflows like building, testing, and deploying your code right from your GitHub repository.

Key Concepts of GitHub Actions

Understanding the components of GitHub Actions makes it much easier to automate your workflows. Here are the building blocks:

Workflow

A workflow is an automated process you define in your repo, described in YAML files stored in .github/workflows/. Workflows are triggered by specific events, such as a push, pull request, or even on a schedule.

Runners

A runner is a server that runs your workflows. GitHub provides hosted runners (like ubuntu-latest), but you can also set up your own self-hosted runner.

Jobs

A job is a group of steps that are executed together, on the same runner. Each job runs in a fresh environment, ensuring isolation and repeatability.

Steps

Steps are single tasks inside a job. A step might be a Shell snippet (run:) or a reusable action (uses:). The success of a step is determined by the exit code: zero for success, nonzero for failure.

Example: Test and Run in Miniconda Environment

Let's see how it all comes together with a simple workflow that installs Miniconda, sets up dependencies, and runs your Python code.

name: Test and Run in Miniconda Environment

# Triggers the workflow on push or pull request events
on: [push, pull_request]

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
    - name: Checkout code
      run: |
        git clone ${{ github.repositoryUrl }}
        cd $(basename ${{ github.repository }} )

    - name: Download Miniconda installer
      run: |
        wget https://repo.anaconda.com/miniconda/Miniconda3-latest-Linux-x86_64.sh -O miniconda.sh

    - name: Install Miniconda
      run: |
        bash miniconda.sh -b -p $HOME/miniconda
        echo "$HOME/miniconda/bin" >> $GITHUB_PATH

    - name: Initialize conda
      run: |
        source $HOME/miniconda/bin/activate
        conda init bash

    - name: Verify conda installation
      run: conda --version

    - name: Install dependencies
      run: |
        conda install -y numpy pandas

    - name: Run your code
      run: |
        python your_script.py

What happens in this workflow?

• Checks out your code so it's available to the runner.
• Downloads and installs Miniconda.
• Initializes conda and verifies that it works.
• Installs your dependencies (here, numpy and pandas).
• Runs your Python script - as you'd do locally!