[Discussion] Override default client ids/secrets

[SamuAlfageme]

For enterprise installations we've always been considering how interesting could be to limit the authorized clients to prevent unwanted clients from connecting instances.

Check for some environment/build-time variables set, if present, use them (e.g. on application's Makefile) to pre-populate the DB:

• OAUTH2_DESKTOP_ID
• OAUTH2_DESKTOP_SECRET
• [OAUTH2_DESKTOP_REDIRECTION_URL]
• ... (the same for iOS, Android clients)

If not, use the default values coming from #38 - the admin will always be able to generate more id/secret/url triplets and delete the existing ones.

Also, maybe would be interesting to offer a third option: don't pre-populate the DB and let the admin generate its own using the webUI provided (maybe too similar to the previous option - i.e. remove all existing pairs on a fresh app installation)

Thoughts? @michaelstingl @felixboehm @pmaier1 @DeepDiver1975

[pmaier1]

Yes, we want this. Then we will also need an ability to add the ids/secrets in the clients used via e.g. ownBrander.

Edit: Ah perfect, you already opened a ticket here https://github.com/owncloud/ownbrander/issues/749