Use User.FirstName instead of trying to infer a user's first name from their nickname in multiple places.

api/post.go

@@ -301,10 +301,7 @@ func fireAndForgetNotifications(post *model.Post, teamId, teamUrl string) {
 
 						// If turned on, add the user's case sensitive first name
 						if profile.NotifyProps["first_name"] == "true" {
-							splitName := strings.Split(profile.Nickname, " ")
-							if len(splitName) > 0 && splitName[0] != "" {
-								keywordMap[splitName[0]] = append(keywordMap[splitName[0]], profile.Id)
-							}
+							keywordMap[profile.FirstName] = append(keywordMap[profile.FirstName], profile.Id)
 						}
 					}
 
@@ -395,10 +392,8 @@ func fireAndForgetNotifications(post *model.Post, teamId, teamUrl string) {
 						continue
 					}
 
-					firstName := strings.Split(profileMap[id].Nickname, " ")[0]
-
 					bodyPage := NewServerTemplatePage("post_body", teamUrl)
-					bodyPage.Props["Nickname"] = firstName
+					bodyPage.Props["Nickname"] = profileMap[id].FirstName
 					bodyPage.Props["TeamName"] = teamName
 					bodyPage.Props["ChannelName"] = channelName
 					bodyPage.Props["BodyText"] = bodyText

api/user.go

@@ -181,14 +181,14 @@ func CreateUser(c *Context, team *model.Team, user *model.User) *model.User {
 			l4g.Error("Encountered an issue joining default channels user_id=%s, team_id=%s, err=%v", ruser.Id, ruser.TeamId, err)
 		}
 
-		//fireAndForgetWelcomeEmail(strings.Split(ruser.Nickname, " ")[0], ruser.Email, team.Name, c.TeamUrl+"/channels/town-square")
+		//fireAndForgetWelcomeEmail(ruser.FirstName, ruser.Email, team.Name, c.TeamUrl+"/channels/town-square")
 
 		if user.EmailVerified {
 			if cresult := <-Srv.Store.User().VerifyEmail(ruser.Id); cresult.Err != nil {
 				l4g.Error("Failed to set email verified err=%v", cresult.Err)
 			}
 		} else {
-			FireAndForgetVerifyEmail(result.Data.(*model.User).Id, strings.Split(ruser.Nickname, " ")[0], ruser.Email, team.Name, c.TeamUrl)
+			FireAndForgetVerifyEmail(result.Data.(*model.User).Id, ruser.FirstName, ruser.Email, team.Name, c.TeamUrl)
 		}
 
 		ruser.Sanitize(map[string]bool{})

web/web.go

@@ -351,7 +351,7 @@ func verifyEmail(c *api.Context, w http.ResponseWriter, r *http.Request) {
 			return
 		} else {
 			user := result.Data.(*model.User)
-			api.FireAndForgetVerifyEmail(user.Id, strings.Split(user.Nickname, " ")[0], user.Email, domain, c.TeamUrl)
+			api.FireAndForgetVerifyEmail(user.Id, user.FirstName, user.Email, domain, c.TeamUrl)
 			http.Redirect(w, r, "/", http.StatusFound)
 			return
 		}