Preparing the containers for the integration test

Before we really talk about the integration test, let's prepare our containers for testing. We use docker-compose in our development environment, but currently, all of our application settings are in the same docker-compose.yml file.

docker-compose allows us to override settings by passing docker-compose.yml files into jail, as shown in the following example:

$  docker-compose -f docker-compose.yml -f docker-compose.test.yml up --build –d

Let's separate the settings and create different docker-compose files. Each file will be for a specific environment. We will create a new file, docker-compose.test.yml. This file has only the settings that we want to overwrite:

version: '3'
services:
  users_service:
    environment:
      - DATABASE_URL=postgresql://postgres:postgres@users_service_db:5432/users_test?sslmode...