Continuous Integration¶

In this exercise you will create a simple Continuous Integration workflow.

What CI does¶

When anyone pushes to a remote git repository, the git server should:

create an empty virtual computer
clone the repository
install all dependencies
run automated tests
report whether the tests succeed or fail

Step 1: Preparations¶

You need:

a GitHub repo for your project
a requirements.txt file
at least one automated test

Step 2: Create a workflow¶

GitHub Actions needs instructions how to install the program.

Create a folder .github/workflows/. Place a text file run_tests.yml into that folder containing the following:

name: run_tests

on:
  push:
    branches: [ main ]

jobs:
  build:

    runs-on: ubuntu-latest

    steps:
    - uses: actions/checkout@v2
    - name: Set up Python 3.11
      uses: actions/setup-python@v2
      with:
        python-version: 3.11
    - name: Install dependencies
      run: |
        python -m pip install --upgrade pip
        pip install -r requirements.txt
    - name: Test with pytest
      run: |
        pytest

Step 3: Requirements¶

A best practice is to have a separate file for development requirements.

Create a separate file dev_requirements.txt
Add pytest to it
Add a pip install line to the yml file.

Step 4: Push¶

Commit and push the changes.

Step 5: Observe¶

Go to GitHub. Check the Actions tab.
Watch the output of your project building.
Also check your mailbox.

Step 6: Badge¶

Copy the following code into your README.md file:

![Python application](https://github.com/USER/REPO/workflows/run_tests/badge.svg)

Replace USER and REPO by the data of your project. run_tests is the name from the workflow file.

You should see a red or green badge in the README that updates itself.