However, we don’t have to “initialize” the environment with docker-compose up. If we reboot our workstation, we have to start the process again. We can start it in the background with the -d flag. It stays alive until we kill it with ctrl-c. Service Lifecycleĭocker-compose up will start the process in the foreground. Likewise, the connection URI for pg10 should be postgres://localhost:5105/project-y. Therefore, the connection URI for pg9 should be postgres://localhost:5961/project-x. Note that we have mapped port 5961 of our workstation to port 5432 (default Postgres’s port) of the container running the pg9 service. docker-compose down will remove that volume, hence our Postgres data will be deleted. The Postgres image is by default configured to use a Docker volume so that the data persists between docker-compose start|stop|restart subcommand. We should only run this command when we’re done with the project. With docker-compose down, all the records in Postgres are completely wiped out. We can start Postgres in a pristine state with just one simple command: docker-compose up -dĪnd clean the slate with this: $ docker-compose down With this docker-compose.yml file: version: '3' The beauty of using Docker is the fact that we can start these services with a clean slate and clean the slate when we’re done.

We’ll use Docker Compose to manage two instances of Postgres (i.e.

Initialize and Reset the Postgres Services Note that we’re not “dockerizing” the applications themselves instead, we’re using Docker Compose as an alternative to Homebrew to fetch and run Postgres. With Docker Compose, both installing and running are easy. Why not Homebrew? With Homebrew, installing multiple versions of Postgres is easy, but running them simultaneously is cumbersome. How do we get different versions of Postgres running simultaneously on our workstation without making any modifications to these projects? One easy way is to use Docker Compose. These projects aren’t using Docker to manage their Postgres dependency so it is up to each developer to manage this themselves. Say we have Project X and Project Y that require Postgres 9 and Postgres 10 respectively.

Postgresql docker