Hi Timo,
You can use the Services API for the authentication for the websocket connection to Users:
https://sdk.innovaphone.com/doc/appwebsocket/Services.htm
Then you can send UserData to get the IDs of every user (with % as filter you will receive the first 100 Users, to get the next 100 you must send the same message but with 100 as offset):
{"mt":"NumUsersResult","src":"usersadmin","numUsers":261,"maxID":18548625}
{"mt":"NumUsersResult","src":"usersadmin","numUsers":261,"maxID":18548625}
{"mt":"UserData","maxID":18548625,"offset":0,"filter":"%","update":false,"col":"id","asc":true,"src":"usersadmin"}
{"mt":"UserDataInfo","src":"usersadmin","id":"32","username":"atlantis","dn":"","cn":"Atlantis"}
...
{"mt":"UserDataResult","src":"usersadmin","result":"ok"}
Then you can use SetPicture to set the profile picture (small, medium and large on base64) for every user:
{ "mt":"SetPicture", "src":"test", "ids":[{32}],"data":"small","picture":"data:image/jpeg;base64,/9j/4AAQ..." }
{ "mt":"SetPictureResult" }
{ "mt":"SetPicture", "src":"test", "ids":[{32}],"data":"medium","picture":"data:image/jpeg;base64,/9j/4AAQ..." }
{ "mt":"SetPictureResult" }
{ "mt":"SetPicture", "src":"test", "ids":[{32}],"data":"large","picture":"data:image/jpeg;base64,/9j/4AAQ..." }
{ "mt":"SetPictureResult" }
Regards,
Carmen