Django + Docker + SQLite3：如何将本地数据库挂载至容器？

Looks like you're on the right track with your docker-compose setup, but let's walk through the key steps to ensure your local database is properly accessible to your Dockerized Django app:

1. Align Django's Database Settings with Container Paths #

First, confirm your Django settings.py points to the exact path of the SQLite file inside the container. Based on your current volume mount, that should be:

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',
        'NAME': '/code/db.sqlite3',  # Matches the container path you mounted
    }
}

If you ever decide to mount the entire db_data directory instead of just the file (a cleaner approach for future maintenance), update the path to /code/db_data/db.sqlite3 here and adjust your volumes in docker-compose accordingly.

2. Validate Your Volume Configuration #

Your current docker-compose volume setup is mostly correct, but let's double-check the full config to avoid gaps:

version: "3"
services:
  web:
    build: ./web/
    ports:
      - "8001:8001"
    volumes:
      - ./web:/code  # Mounts your local Django project to /code in the container
      - /home/cosmo/db_data/db.sqlite3:/code/db.sqlite3  # Mounts local DB to container path
    command: python manage.py runserver 0.0.0.0:8001

Just ensure the absolute path to your local db.sqlite3 is accurate—typos here will cause Django to create a new empty database instead of using your existing one.

3. Fix File Permission Issues (Critical!) #

Docker containers often run as a specific user (root by default, or a non-root user if your Dockerfile defines one), and this user needs read/write access to your local SQLite file.

• If using root (default): Run these commands on your host machine to grant root access:

  sudo chmod 664 /home/cosmo/db_data/db.sqlite3
  sudo chown root:root /home/cosmo/db_data/db.sqlite3
  

• If using a non-root user: If your Dockerfile creates a user with UID 1000 (common for matching host user permissions), update the file ownership on your host:

  sudo chown 1000:1000 /home/cosmo/db_data/db.sqlite3
  

Alternatively, you can add user: "1000:1000" to your web service in docker-compose.yml to run the container as your host user, which avoids permission headaches entirely.

4. Test the Setup #

Start your containers with:

docker-compose up --build

Then, verify the database is accessible by running a Django shell inside the container:

docker-compose exec web python manage.py shell

In the shell, run a quick check to confirm your data is present (replace MyModel with one of your actual models):

from myapp.models import MyModel
print(MyModel.objects.count())

If this returns the number of records from your local database, you're good to go!

Troubleshooting Common Problems #

• Empty database: Double-check the NAME path in settings.py matches the container's mounted file path, and ensure your host path in docker-compose has no typos.
• Permission denied: Adjust file permissions as outlined in step 3, or run the container with a user that has access to the file.
• Database locked: SQLite doesn't handle concurrent writes well—make sure no local processes (like your local Django dev server) are using the database while the container is running.

内容的提问来源于stack exchange，提问作者idature