I have a bunch of players that have signed up during the alpha, where they have been registered with email and username and password.
I'm now integrating Steam. When the game is eventually released, people will be signed up with their Steam account instead. Until then, I need the email registration to be open (maybe even after launch I need them to work in parallell, if I distribute the game outside Steam, or for testing accounts).
When the Steam registration is done, the player does not get a PlayFab username. (That is not ideal, since it makes it much harder to get an overview in the Players and LeaderBoard and many other sections in PlayFab's web gui.) *see note 3 below though
So, I'm consider making a call to playfab after the Steam registration and set a Username, for instance to the users Steam account name.
1) The problem I first came to think of was how I then could enforce unique Usernames. Any good suggestion? Use a prefix maybe, like s_MySteamName or something?
2) While writing this post, I realized that even then, it wouldn't be that easy. AddUsernamePasswordRequest requires a password, and that isn't what I want to do. I saw that you talked about potentially allowing post-account-creation setting of Usernames in some other thread (April 2016), but not sure if this is even possible?
3*) Also, when writing this post, I realized after testing it that the field "Display name" is actually shown in the web gui pages in the absense of a Username. Could this be the answer to it all maybe? I.e upon account creation, make a UpdateUserTitleDisplayNameRequest request? And then change everywhere in the game where I show the player's Username to instead show the DisplayName?
Sorry for the somewhat confusing unorganized topic/rambling. I guess I just want some input if I'm approaching this from the right angle or if there's something I need to think about. :)