[PYTHON] Steps to create a Job that pulls a Docker image and tests it with Github Actions

This time, I practiced to do pytest on the image of docker-compose with Github Actions for the repository of the Python project, so I will write the memo.

Prerequisites

--Create a token for packages on Github. --Docker login. --Register a token number that allows you to package Secrets in any repository on Github.
(Registered as GHCR_IO_TOKEN in my environment.)

Folder structure

repository/             #Repository directory
　├ .github/
　│　├ workflows/
　│　│　└ sample.yml     #Github actions file
　├ project/
　│　├ sample/           #(Explanation omitted)
　│　│　├ __init__.py
　│　│　└ add.py
　│　└ test/             #(Explanation omitted)
　│　　　├ __init__.py   
　│　　　└ test_add.py
　├ docker-compose.yml   #Detailed description later
　├ Dockerfile           #Appropriate Python image (explanation omitted)
　└ requirements.txt     #Describe the appropriate package (only pytest is described this time)

procedure

1. ghcr.io for image in docker-compose.yml Enter the specified image name.
2. After creating an image with docker-compose up, push the image with docker-compose push
3. Pull on the github actions file and do a pytest!

Upload the image to ghcr.io.

Specify the image as follows.

docker-compose.yml

 services:
    python:
        build: .
        #image: ghcr.io/Github username/Repository name/Image name:Tag name
        image: ghcr.io/n-jun-k2/sample-actions/python:v1

Create an image locally and push it.

#For the time being, create an image as usual
docker-compose up -d 
#Push image
docker-compose push

About CI files on Github Actions

Please change ... appropriately. I'm checking out, logging in, pulling and doing a pytest.

yml:.github/workflows/sample.yml

name: ...
on:
  ...

jobs:
  ...:
    name: ...
    runs-on: ubuntu-20.04
    steps:
        - name: Checkout                                         #Check out
          uses: actions/checkout@v2
        - name: Login to Docker                                  #docker login
          uses: docker/login-action@v1
          with:
            registry: ghcr.io
            username: ${{ github.repository_owner }}
            password: ${{ secrets.GHCR_IO_TOKEN }}
        - name: Set up Docker                                    #Pull to launch the image
          run: |
            docker pull ghcr.io/n-jun-k2/sample-actions/python:v1
            docker-compose up -d
        - name: Run test                                         #Do a pytest.
          run: docker-compose exec -T python pytest

This CI file will pytest on the docker-compose image.

Note that don't forget to include the -T option below! I'll get an error

docker-compose exec -T python pytest