Hi Xavier,
To get an api key, you’ll need to log in. Take a look at the docs for more info. This is what happens when you log in. Each token is valid for 72 hours - you can get a new valid token in exchange for a valid token. After that period, you’ll need to log in again.
I know this is not the way this is done usually, but for now it works 
Might change in the future.
Konrad