This is why we would like to share how we unify our Ruby on Rails environments with Docker Compose.

We deploy multiple times a day and that is why we want to spend as little time as possible on manual QA.

Docker Mysql Rails Code Coverage Of

Our test suite contains more than 14.000 unit, functional and integration tests with a code coverage of 98.

The build process of our core application has various runtime and infrastructure dependencies including.

This is why I want to outline how we use Docker Compose to solve this problem for us.

Parts of our frontend uses webpack and so we also add the repositories for nodejs and yarn.

The spring and server services use a little script (validate-migrated.sh) to determine if migrations were already executed.

If yes, we run possibly pending migrations rails db:migrate, otherwise we execute the more efficient rails db:setup.

This can cause problems when running multiple tests in parallel but we can use the -project-name flag of docker-compose with e.g.

PROJECTNAME(TZUTC date YmdHMS)(cat devurandom tr -dc a-zA-Z0-9 fold -w 8 head -n 1).

Similar to the wrapper script above we can create a shell alias to make things simpler.

The actual dependencies for development and CI environments can be boiled down to docker and docker-compose.

Some of our developers use OSX, others different Linux distributions and some even Windows.

Docker Mysql Rails How To Setup The

With Docker Compose we now no longer need to maintain separate documents for how to setup the development environment.

Instead of executing manual steps this process is now also fully automated.

There is no need to install any of these new dependencies in either the development environment or on our CI servers.

Also, this makes sure that all environments use the very same well-defined versions of all components.

Instead, we frequently push our local changes to a remote branch on GitHub and our CI infrastructure automatically builds all these pushes.

To reduce these feedback cycles it is necessary for us to run our tests in parallel and on multiple CI servers.