5813 - Auslagerung der Map Credentials

[zaziemo]

To actually answer on how to add configuration and how to get it into the frontend:

You can introduce new settings by providing (possibly empty) default values in config/defaults.yml, and adding commented examples in config/diaspora.yml.example. These will then become available as AppConfig.key.subkey.subsubkey. You can then pass them along to the frontend here and access them via gon.appConfig.foo.bar in the JS.

And thinking about it please do so, if @denschub has luck in obtaining an API key we can redistribute, just skip the step of adding examples in config/diaspora.yml.example and add it as default.