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var err = "ERR_LOGIN_FAIL";

if (username != nil) and (username != "") and (pw != nil) and (pw != "") then

      pw = Base64_Encode(username + ":" + pw);    

      var db = Wub_GetDB(site);
      var coll = Wub_GetCollection(db, "login");

      var dbobj = Wub_NewDBObject([. pw=pw .]); 
      var res = Wub_QueryDB(coll, dbobj, 20);
      if (Size(res) == 1) then
         var key = Base64_Encode(ToString(Wub_RandomInt(999999999999999)));
         coll = Wub_GetCollection(db, "session");
         var data = res[0];
         DeleteField(data, "pw");
         dbobj = Wub_NewDBObject([. key=key, data=data .]); 
         Wub_InsertDB(coll, dbobj);
         WubCall(succCmd, [key]);
         key
      else
        err = "ERR_AUTHENTICATION_ERROR";
        WubCall(errCmd, [err]);
        err
      end;
else
   err = "ERR_EMPTY_LOGIN";
   WubCall(errCmd, [err]);
   err
end;