Move away from the "andForget" style of function (#3043)

As suggested by @crspeller here:
https://github.com/mattermost/platform/pull/3022#issuecomment-220004020

api/oauth.go

@@ -636,5 +636,5 @@ func CompleteSwitchWithOAuth(c *Context, w http.ResponseWriter, r *http.Request,
 		return
 	}
 
-	sendSignInChangeEmailAndForget(c, user.Email, c.GetSiteURL(), strings.Title(service)+" SSO")
+	go sendSignInChangeEmail(c, user.Email, c.GetSiteURL(), strings.Title(service)+" SSO")
 }

api/user.go

@@ -90,7 +90,7 @@ func createUser(c *Context, w http.ResponseWriter, r *http.Request) {
 	hash := r.URL.Query().Get("h")
 	teamId := ""
 	var team *model.Team
-	sendWelcomeEmail := true
+	shouldSendWelcomeEmail := true
 	user.EmailVerified = false
 
 	if len(hash) > 0 {
@@ -120,7 +120,7 @@ func createUser(c *Context, w http.ResponseWriter, r *http.Request) {
 
 		user.Email = props["email"]
 		user.EmailVerified = true
-		sendWelcomeEmail = false
+		shouldSendWelcomeEmail = false
 	}
 
 	inviteId := r.URL.Query().Get("iid")
@@ -170,11 +170,11 @@ func createUser(c *Context, w http.ResponseWriter, r *http.Request) {
 			return
 		}
 
-		addDirectChannelsAndForget(team.Id, ruser)
+		go addDirectChannels(team.Id, ruser)
 	}
 
-	if sendWelcomeEmail {
+	if shouldSendWelcomeEmail {
-		sendWelcomeEmailAndForget(c, ruser.Id, ruser.Email, c.GetSiteURL(), ruser.EmailVerified)
+		go sendWelcomeEmail(c, ruser.Id, ruser.Email, c.GetSiteURL(), ruser.EmailVerified)
 	}
 
 	w.Write([]byte(ruser.ToJson()))
@@ -330,7 +330,7 @@ func CreateOAuthUser(c *Context, w http.ResponseWriter, r *http.Request, service
 				return nil
 			}
 
-			addDirectChannelsAndForget(team.Id, user)
+			go addDirectChannels(team.Id, user)
 		}
 	}
 
@@ -342,9 +342,7 @@ func CreateOAuthUser(c *Context, w http.ResponseWriter, r *http.Request, service
 	return ruser
 }
 
-func sendWelcomeEmailAndForget(c *Context, userId string, email string, siteURL string, verified bool) {
+func sendWelcomeEmail(c *Context, userId string, email string, siteURL string, verified bool) {
-	go func() {
-
 	subjectPage := utils.NewHTMLTemplate("welcome_subject", c.Locale)
 	subjectPage.Props["Subject"] = c.T("api.templates.welcome_subject", map[string]interface{}{"TeamDisplayName": siteURL})
 
@@ -365,11 +363,9 @@ func sendWelcomeEmailAndForget(c *Context, userId string, email string, siteURL
 	if err := utils.SendMail(email, subjectPage.Render(), bodyPage.Render()); err != nil {
 		l4g.Error(utils.T("api.user.send_welcome_email_and_forget.failed.error"), err)
 	}
-	}()
 }
 
-func addDirectChannelsAndForget(teamId string, user *model.User) {
+func addDirectChannels(teamId string, user *model.User) {
-	go func() {
 	var profiles map[string]*model.User
 	if result := <-Srv.Store.User().GetProfiles(teamId); result.Err != nil {
 		l4g.Error(utils.T("api.user.add_direct_channels_and_forget.failed.error"), user.Id, teamId, result.Err.Error())
@@ -404,12 +400,9 @@ func addDirectChannelsAndForget(teamId string, user *model.User) {
 	if result := <-Srv.Store.Preference().Save(&preferences); result.Err != nil {
 		l4g.Error(utils.T("api.user.add_direct_channels_and_forget.failed.error"), user.Id, teamId, result.Err.Error())
 	}
-	}()
 }
 
-func SendVerifyEmailAndForget(c *Context, userId, userEmail, siteURL string) {
+func SendVerifyEmail(c *Context, userId, userEmail, siteURL string) {
-	go func() {
-
 	link := fmt.Sprintf("%s/do_verify_email?uid=%s&hid=%s&email=%s", siteURL, userId, model.HashPassword(userId), url.QueryEscape(userEmail))
 
 	subjectPage := utils.NewHTMLTemplate("verify_subject", c.Locale)
@@ -426,7 +419,6 @@ func SendVerifyEmailAndForget(c *Context, userId, userEmail, siteURL string) {
 	if err := utils.SendMail(userEmail, subjectPage.Render(), bodyPage.Render()); err != nil {
 		l4g.Error(utils.T("api.user.send_verify_email_and_forget.failed.error"), err)
 	}
-	}()
 }
 
 func login(c *Context, w http.ResponseWriter, r *http.Request) {
@@ -1285,15 +1277,15 @@ func updateUser(c *Context, w http.ResponseWriter, r *http.Request) {
 		rusers := result.Data.([2]*model.User)
 
 		if rusers[0].Email != rusers[1].Email {
-			sendEmailChangeEmailAndForget(c, rusers[1].Email, rusers[0].Email, c.GetSiteURL())
+			go sendEmailChangeEmail(c, rusers[1].Email, rusers[0].Email, c.GetSiteURL())
 
 			if utils.Cfg.EmailSettings.RequireEmailVerification {
-				SendEmailChangeVerifyEmailAndForget(c, rusers[0].Id, rusers[0].Email, c.GetSiteURL())
+				go SendEmailChangeVerifyEmail(c, rusers[0].Id, rusers[0].Email, c.GetSiteURL())
 			}
 		}
 
 		if rusers[0].Username != rusers[1].Username {
-			sendEmailChangeUsernameAndForget(c, rusers[1].Username, rusers[0].Username, rusers[0].Email, c.GetSiteURL())
+			go sendEmailChangeUsername(c, rusers[1].Username, rusers[0].Username, rusers[0].Email, c.GetSiteURL())
 		}
 
 		rusers[0].Password = ""
@@ -1365,7 +1357,7 @@ func updatePassword(c *Context, w http.ResponseWriter, r *http.Request) {
 	} else {
 		c.LogAudit("completed")
 
-		sendPasswordChangeEmailAndForget(c, user.Email, c.GetSiteURL(), c.T("api.user.update_password.menu"))
+		go sendPasswordChangeEmail(c, user.Email, c.GetSiteURL(), c.T("api.user.update_password.menu"))
 
 		data := make(map[string]string)
 		data["user_id"] = uresult.Data.(string)
@@ -1767,14 +1759,12 @@ func ResetPassword(c *Context, userId, newPassword string) *model.AppError {
 		return result.Err
 	}
 
-	sendPasswordChangeEmailAndForget(c, user.Email, c.GetSiteURL(), c.T("api.user.reset_password.method"))
+	go sendPasswordChangeEmail(c, user.Email, c.GetSiteURL(), c.T("api.user.reset_password.method"))
 
 	return nil
 }
 
-func sendPasswordChangeEmailAndForget(c *Context, email, siteURL, method string) {
+func sendPasswordChangeEmail(c *Context, email, siteURL, method string) {
-	go func() {
-
 	subjectPage := utils.NewHTMLTemplate("password_change_subject", c.Locale)
 	subjectPage.Props["Subject"] = c.T("api.templates.password_change_subject",
 		map[string]interface{}{"TeamDisplayName": utils.Cfg.TeamSettings.SiteName, "SiteName": utils.Cfg.TeamSettings.SiteName})
@@ -1788,13 +1778,9 @@ func sendPasswordChangeEmailAndForget(c *Context, email, siteURL, method string)
 	if err := utils.SendMail(email, subjectPage.Render(), bodyPage.Render()); err != nil {
 		l4g.Error(utils.T("api.user.send_password_change_email_and_forget.error"), err)
 	}
-
-	}()
 }
 
-func sendEmailChangeEmailAndForget(c *Context, oldEmail, newEmail, siteURL string) {
+func sendEmailChangeEmail(c *Context, oldEmail, newEmail, siteURL string) {
-	go func() {
-
 	subjectPage := utils.NewHTMLTemplate("email_change_subject", c.Locale)
 	subjectPage.Props["Subject"] = c.T("api.templates.email_change_subject",
 		map[string]interface{}{"TeamDisplayName": utils.Cfg.TeamSettings.SiteName})
@@ -1809,13 +1795,9 @@ func sendEmailChangeEmailAndForget(c *Context, oldEmail, newEmail, siteURL strin
 	if err := utils.SendMail(oldEmail, subjectPage.Render(), bodyPage.Render()); err != nil {
 		l4g.Error(utils.T("api.user.send_email_change_email_and_forget.error"), err)
 	}
-
-	}()
 }
 
-func SendEmailChangeVerifyEmailAndForget(c *Context, userId, newUserEmail, siteURL string) {
+func SendEmailChangeVerifyEmail(c *Context, userId, newUserEmail, siteURL string) {
-	go func() {
-
 	link := fmt.Sprintf("%s/do_verify_email?uid=%s&hid=%s&email=%s", siteURL, userId, model.HashPassword(userId), url.QueryEscape(newUserEmail))
 
 	subjectPage := utils.NewHTMLTemplate("email_change_verify_subject", c.Locale)
@@ -1834,12 +1816,9 @@ func SendEmailChangeVerifyEmailAndForget(c *Context, userId, newUserEmail, siteU
 	if err := utils.SendMail(newUserEmail, subjectPage.Render(), bodyPage.Render()); err != nil {
 		l4g.Error(utils.T("api.user.send_email_change_verify_email_and_forget.error"), err)
 	}
-	}()
 }
 
-func sendEmailChangeUsernameAndForget(c *Context, oldUsername, newUsername, email, siteURL string) {
+func sendEmailChangeUsername(c *Context, oldUsername, newUsername, email, siteURL string) {
-	go func() {
-
 	subjectPage := utils.NewHTMLTemplate("username_change_subject", c.Locale)
 	subjectPage.Props["Subject"] = c.T("api.templates.username_change_subject",
 		map[string]interface{}{"TeamDisplayName": utils.Cfg.TeamSettings.SiteName})
@@ -1855,7 +1834,6 @@ func sendEmailChangeUsernameAndForget(c *Context, oldUsername, newUsername, emai
 		l4g.Error(utils.T("api.user.send_email_change_username_and_forget.error"), err)
 	}
 
-	}()
 }
 
 func updateUserNotify(c *Context, w http.ResponseWriter, r *http.Request) {
@@ -2055,7 +2033,7 @@ func oauthToEmail(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	sendSignInChangeEmailAndForget(c, user.Email, c.GetSiteURL(), c.T("api.templates.signin_change_email.body.method_email"))
+	go sendSignInChangeEmail(c, user.Email, c.GetSiteURL(), c.T("api.templates.signin_change_email.body.method_email"))
 
 	RevokeAllSession(c, c.Session.UserId)
 	if c.Err != nil {
@@ -2131,7 +2109,7 @@ func emailToLdap(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	sendSignInChangeEmailAndForget(c, user.Email, c.GetSiteURL(), "LDAP")
+	go sendSignInChangeEmail(c, user.Email, c.GetSiteURL(), "LDAP")
 
 	m := map[string]string{}
 	m["follow_link"] = "/login?extra=signin_change"
@@ -2201,7 +2179,7 @@ func ldapToEmail(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	sendSignInChangeEmailAndForget(c, user.Email, c.GetSiteURL(), c.T("api.templates.signin_change_email.body.method_email"))
+	go sendSignInChangeEmail(c, user.Email, c.GetSiteURL(), c.T("api.templates.signin_change_email.body.method_email"))
 
 	m := map[string]string{}
 	m["follow_link"] = "/login?extra=signin_change"
@@ -2210,9 +2188,7 @@ func ldapToEmail(c *Context, w http.ResponseWriter, r *http.Request) {
 	w.Write([]byte(model.MapToJson(m)))
 }
 
-func sendSignInChangeEmailAndForget(c *Context, email, siteURL, method string) {
+func sendSignInChangeEmail(c *Context, email, siteURL, method string) {
-	go func() {
-
 	subjectPage := utils.NewHTMLTemplate("signin_change_subject", c.Locale)
 	subjectPage.Props["Subject"] = c.T("api.templates.singin_change_email.subject",
 		map[string]interface{}{"SiteName": utils.ClientCfg["SiteName"]})
@@ -2226,8 +2202,6 @@ func sendSignInChangeEmailAndForget(c *Context, email, siteURL, method string) {
 	if err := utils.SendMail(email, subjectPage.Render(), bodyPage.Render()); err != nil {
 		l4g.Error(utils.T("api.user.send_sign_in_change_email_and_forget.error"), err)
 	}
-
-	}()
 }
 
 func verifyEmail(c *Context, w http.ResponseWriter, r *http.Request) {
@@ -2274,9 +2248,9 @@ func resendVerification(c *Context, w http.ResponseWriter, r *http.Request) {
 		user := result.Data.(*model.User)
 
 		if user.LastActivityAt > 0 {
-			SendEmailChangeVerifyEmailAndForget(c, user.Id, user.Email, c.GetSiteURL())
+			go SendEmailChangeVerifyEmail(c, user.Id, user.Email, c.GetSiteURL())
 		} else {
-			SendVerifyEmailAndForget(c, user.Id, user.Email, c.GetSiteURL())
+			go SendVerifyEmail(c, user.Id, user.Email, c.GetSiteURL())
 		}
 	}
 }