Docker: how to manage development and production settings?

Question

I'm just getting started with Docker. With the official NGINX image on my OSX development machine (with Docker Machine as the Docker host) I ran up against the bug with sendfile and VirtualBox which means the server fails to show changes I make to files.

The workaround for this is to use a modified nginx.conf file that turns off sendfile. This guy's solution has an instruction in the Dockerfile to copy a customised conf file into the container. Alternatively, this guy maps the NGINX configuration to a new folder with modified conf file.

This kind of thing works OK locally. But what if I don't need this modification on my cloud host? How should I handle this and other differences when it comes to deployment?

Answer 1

You could mount your custom nginx.conf into the container in development via e.g. --volume ./nginx/nginx.conf:/etc/nginx/nginx.conf and simply omit this parameter to docker run in production.

If using docker-compose, the two options I would recommend are:

• Employ the limited support for environment variable interpolation and add something like the following under volumes in your container definition: ./nginx/nginx.${APP_ENV}.conf:/etc/nginx/nginx.conf

• Use a separate YAML file for production overrides.