Postgres Docker Container Setup

I prefer running Postgres databases in Docker containers, instead of with the standalone MacOS app or Linux packages. Configuring and managing Postgres instances with Docker offers a way better dev experience (especially when paired with Postico 2) and has great support for targeting specific versions of Postgres.

Files Needed for a Dockerized Postgres Instance

docker-compose.yml

services:
  db:
    image: postgres
    restart: always
    shm_size: 128mb
    env_file:
      - path: ./.env
        required: true
      - path: ./.env.local
        required: false
    volumes:
      - ./init.sql:/docker-entrypoint-initdb.d/init.sql
      - ./data:/var/lib/postgresql/data
    ports:
      - 5432:5432

Compose File Notes

• The first line under volumes initializes new databases with a hypothetical init.sql file. If you do not need this, simply remove that line to skip the initialization step.
• This config supports an optional .env.local file to add environment-specific overrides that can/should be added to .gitignore.

.env

I use an .env file to track the expected/required fields, and override them in an .env.local file with actual logins on a per-environment basis.

This allows me to define the necessary connection values once for use on the Docker container configs and whatever CRUD app I might be building alongside the database.

POSTGRES_DB=db_name
POSTGRES_USER=db_user
POSTGRES_PASSWORD=db_pass

.gitignore

Environment-specific overrides and Postgres database files should not be tracked in git.

.env.local
data

Running The Postgres Docker Image

After setting up the config files above, you can run docker compose up -d in the project root to start the Postgres database instance.

To stop the database instance, run docker compose down in the same directory.