CI/CD pipeline and Docker

This is a memo when I learned the CI/CD pipeline using Docker.

What is CI/CD?

Image quote: ThikIT "DevOps, containers are a big success in CI/CD pipelines!"

Systematize the process for continuous integration and continuous delivery (deployment). The following are typical CI tools.

• Jenkins
• Travis CI
• circleci
• Git Hub Actions

CI/CD and Git commands

An example using Travis CI + Docker + Heroku + Rails. Only Travis CI flow and Git command are described.

Store the following YAML file in the work directory.

sudo: required

services: docker

before_install:
  - docker-compose up --build -d
  - docker login -u "$HEROKU_USERNAME" -p "$HEROKU_API_KEY" registry.heroku.com 

script:
  - docker-compose exec --env 'RAILS_ENV=test' web rails db:create
  - docker-compose exec --env 'RAILS_ENV=test' web rails db:migrate
  - docker-compose exec --env 'RAILS_ENV=test' web rails test

deploy:
  provider: script
  script:
    docker build -t registry.heroku.com/$HEROKU_APP_NAME/web -f Dockerfile.prod .;
    docker push registry.heroku.com/$HEROKU_APP_NAME/web;
    heroku run --app $HEROKU_APP_NAME rails db:migrate;
  on:
    branch: master

Permission setting, using Docker, container startup, DB preparation, test execution, deployment execution (only when the git branch is master) are described in order.

Create a feature branch

$ git checkout -b feature

Bring modified files to Git staging

$ git add .

Commit your changes

$ git commit -m '<commit message>'

push to feature branch

$ git push origin feature

The Travis CI build runs and the test code runs.

Create a pull request on GitHub ・ Merge

By being reflected in the Master branch in Git, Travis CI build will run and the application will be deployed.