Using Django with Docker for Local Development

Docker simplifies local development by creating isolated and reproducible environments for your projects. Using Docker with Django ensures that your application runs consistently across different systems, eliminates dependency conflicts, and makes it easier to collaborate with team members.

This guide explains how to set up Django with Docker for local development, covering the creation of Docker images, setting up services, and running your application.

Benefits of Using Docker for Django Development

1. Consistency: Ensures your application runs the same across all environments.
2. Isolation: Keeps dependencies and configurations separate from your local machine.
3. Portability: Easy to share the development environment with others.
4. Simplified Setup: Quickly spin up required services like databases using pre-configured containers.

Prerequisites

• Install Docker: Download and install Docker Desktop from docker.com.
• Basic knowledge of Docker concepts (containers, images, Dockerfile).

Step 1: Create a Django Project

If you already have a Django project, skip this step. Otherwise, create a new project:

bash
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django-admin startproject myproject
cd myproject

Step 2: Write a Dockerfile

A Dockerfile defines the environment for your Django application. Create a file named Dockerfile in your project root directory and add the following content:

dockerfile
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# Use the official Python image as a base
FROM python:3.10-slim

# Set the working directory
WORKDIR /app

# Copy the requirements file
COPY requirements.txt /app/

# Install dependencies
RUN pip install --no-cache-dir -r requirements.txt

# Copy the Django project into the container
COPY . /app/

# Expose the port the app runs on
EXPOSE 8000

# Default command to run the application
CMD ["python", "manage.py", "runserver", "0.0.0.0:8000"]

Step 3: Create requirements.txt

Generate the requirements.txt file if you haven’t already:

bash
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pip freeze > requirements.txt

Step 4: Set Up docker-compose.yml

Docker Compose allows you to manage multi-container applications (e.g., Django + PostgreSQL). Create a docker-compose.yml file in your project root:

yaml
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version: "3.9"

services:
  web:
    build:
      context: .
    ports:
      - "8000:8000"
    volumes:
      - .:/app
    environment:
      - DEBUG=True
    depends_on:
      - db

  db:
    image: postgres:15
    environment:
      POSTGRES_USER: myuser
      POSTGRES_PASSWORD: mypassword
      POSTGRES_DB: mydatabase
    volumes:
      - postgres_data:/var/lib/postgresql/data

volumes:
  postgres_data:

Step 5: Update settings.py for Docker

Modify your settings.py to use the PostgreSQL database from the Docker setup. Replace the DATABASES section with:

python
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DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.postgresql',
        'NAME': 'mydatabase',
        'USER': 'myuser',
        'PASSWORD': 'mypassword',
        'HOST': 'db',
        'PORT': 5432,
    }
}

Step 6: Build and Run the Containers

1. Build the Docker image:

   bash
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   docker-compose build
   

2. Start the containers:

   bash
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   docker-compose up
   

3. Access the Django application at http://localhost:8000.

Step 7: Run Database Migrations

To initialize your database, run migrations inside the running Docker container:

bash
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docker-compose exec web python manage.py migrate

Step 8: Optional - Create a Superuser

Create an admin user for the Django admin panel:

bash
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docker-compose exec web python manage.py createsuperuser

Step 9: Manage Static Files

During development, configure static files to work seamlessly. Update the settings.py file:

python
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STATIC_URL = '/static/'
STATIC_ROOT = '/app/staticfiles'

Run the collectstatic command:

bash
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docker-compose exec web python manage.py collectstatic

Step 10: Debugging and Logs

To view logs from your containers, use:

bash
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docker-compose logs -f

To stop the containers, run:

bash
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docker-compose down

Folder Structure After Setup

Your project structure should look like this:

markdown
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myproject/
├── Dockerfile
├── docker-compose.yml
├── manage.py
├── myproject/
│   ├── __init__.py
│   ├── settings.py
│   ├── urls.py
│   ├── wsgi.py
├── requirements.txt

Advantages of Using Docker with Django

1. Simplified Collaboration: Share the docker-compose.yml file, and your team can replicate the setup easily.
2. Integrated Services: Add other services like Redis or Celery by updating docker-compose.yml.
3. No Dependency Conflicts: Different projects can use different versions of Python or Django without interference.

Conclusion

Docker revolutionizes local development by providing an isolated and consistent environment for Django projects. By following this guide, you can set up a Docker-based Django environment that simplifies local development, testing, and deployment.