Docker Compose

Part of the Docker course

By now, starting a realistic application takes four commands and none of them are short. Create a network. Create a volume. Start the database with its environment variables and its volume and its network. Start the web server with its network and its published port, in that order, because the database has to exist first.

You will get one of them wrong. Then you will write them into a shell script, and the script will drift out of date, and a new colleague will run it against a machine where the volume already exists with different contents. This is not a hypothetical progression; it is what every team does before they find the tool that fixes it.