Docker environment variables

[gabriel20xx]

The dockerfile (or a startup script) should automatically download configuration.yml and application.properties and insert username, password and ports from the environment variables of docker

[Krillsson]

The application already writes default config files to the config directory.

The ports already support environment variables.

As for the username and password, those are inside a custom configuration file and having placeholders in there is not trivial. So it's best to allow env variable overrides at the place of usage instead. Meaning, we read the env variables in the code where username and password is consumed.

If you are open to submit a PR, here is how to read env variables in spring boot:

https://stackoverflow.com/questions/44803211/read-environment-variable-in-springboot