Entrypoints, Migrationen und collectstatic

Before serving traffic, a container often needs to run migrations and gather static files. Let's automate those startup steps. ⚙️

An entrypoint is a script that runs every time the container starts, right before your main command takes over.

Create entrypoint.sh with a shebang line, so the container knows to run it with the shell.

Run migrate inside the entrypoint, so your database schema is always current when the app starts.

Run collectstatic to copy CSS and JS into one folder that your server can serve in production.

End the script with exec so your app becomes process 1 and receives stop signals cleanly.

Set the script as executable in your Dockerfile so the container can actually run it on startup.

Point ENTRYPOINT at your script, then keep CMD as the command it should run last.

The --noinput flag stops Django from pausing for prompts, which is essential for unattended container startups.

Postgres may boot slowly, so it helps to wait for the db port before migrating to avoid connection errors.

Use docker compose logs to confirm migrations ran and static files were collected on startup.

Why end an entrypoint script with exec on the main command?

Your entrypoint now runs migrate and collectstatic with --noinput, waits for the db, then execs the app as PID 1. Boot-ready every time. ✅