Docker Compose for Django development

I had to get Docker Compose working for a Django project, primarily to make it easier for other developers to get a working development environment.

Some features of this project:

• Uses GeoDjango, so needs GDAL etc for the Django app plus a PostgreSQL server running PostGIS
• Already has a Dockerfile used for the production deployment, but needed a separate one for the development environment
• Makes extensive use of Django migrations (over 100 and counting)

I ended up with this docker-compose.yml file in the root of the project:

version: "3.1"
volumes:
  postgresql-data:
services:
  database:
    image: postgis/postgis:13-3.1
    restart: always
    expose:
      - "5432"
    ports:
      - "5432:5432"
    volumes:
      - postgresql-data:/var/lib/postgresql/data
    environment:
      POSTGRES_USER: postgres
      POSTGRES_DB: mydb
      POSTGRES_PASSWORD: postgres
  web:
    container_name: myapp
    platform: linux/amd64
    build:
      context: .
      dockerfile: Dockerfile.dev
    command: python manage.py runserver 0.0.0.0:3000
    environment:
      DATABASE_URL: postgres://postgres:postgres@database:5432/mydb
      DEBUG: 1
    volumes:
      - .:/app
    ports:
      - "3000:3000"
    depends_on:
      - migrations
      - database
  migrations:
    platform: linux/amd64
    build:
      context: .
      dockerfile: Dockerfile.dev
    command: python manage.py migrate --noinput
    environment:
      DATABASE_URL: postgres://postgres:postgres@database:5432/mydb
    volumes:
      - .:/app
    depends_on:
      - database

The db container runs PostGIS. It uses a named volume to persist PostgreSQL data in between container restarts.

The web container runs the Django development server, built using the custom Dockerfile.dev Dockerfile.

The migrations container simply runs the apps migrations and then terminates - with depends_on used to ensure that migrations run after the hdatabase server starts and before the web server.

Both web and migrations include a platform: linux/amd64 property - this ensures they will work on M1 Macs even if the Python dependencies are not yet easily compiled for that architecture, see Running Docker on an M1 Mac.

The container_name: myapp field on the web container is a convenience which means you can later run commands like this:

docker exec -it myapp ./manage.py collectstatic

Here's Dockerfile.dev:

FROM python:3.9-slim
ENV APP_HOME /app
WORKDIR $APP_HOME
ENV PYTHONUNBUFFERED 1
# gdal for GeoDjango
RUN apt-get update && apt-get install -y \
    binutils \
    gdal-bin \
    libproj-dev \
    git \
    && rm -rf /var/lib/apt/lists/*
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt
WORKDIR $APP_HOME/myapp
RUN ./manage.py collectstatic --no-input
CMD python manage.py runserver 0.0.0.0:3000

Related

• github Running a Django and PostgreSQL development environment in GitHub Codespaces - 2023-08-10
• docker Using pipenv and Docker - 2022-11-28
• macos Running Docker on an M1 Mac - 2021-05-25
• github-actions Talking to a PostgreSQL service container from inside a Docker container - 2020-09-18
• github-actions Running tests against PostgreSQL in a service container - 2021-02-23
• docker Allowing a container in Docker Desktop for Mac to talk to a PostgreSQL server on the host machine - 2022-03-31
• docker Installing packages from Debian unstable in a Docker image based on stable - 2021-03-22
• digitalocean Running Datasette on DigitalOcean App Platform - 2020-10-06
• django Using pytest-django with a reusable Django application - 2024-08-07
• kubernetes Basic Datasette in Kubernetes - 2021-11-05

Created 2021-05-24T22:08:23-07:00, updated 2021-05-26T11:32:27-07:00 · History · Edit