[GITEA] notifies admins on new user registration

Sends email with information on the new user (time of creation and time of last sign-in) and a link to manage the new user from the admin panel

closes: https://codeberg.org/forgejo/forgejo/issues/480

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/1371
Co-authored-by: Aravinth Manivannan <realaravinth@batsense.net>
Co-committed-by: Aravinth Manivannan <realaravinth@batsense.net>
(cherry picked from commit c721aa828b)

custom/conf/app.example.ini

@@ -1453,6 +1453,8 @@ LEVEL = Info
 ;;
 ;; Default configuration for email notifications for users (user configurable). Options: enabled, onmention, disabled
 ;DEFAULT_EMAIL_NOTIFICATIONS = enabled
+;; Send email notifications to all instance admins on new user sign-ups. Options: enabled, true, false
+;NOTIFY_NEW_SIGN_UPS = false
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

modules/notification/base/notifier.go

@@ -64,4 +64,5 @@ type Notifier interface {
 	NotifyRepoPendingTransfer(ctx context.Context, doer, newOwner *user_model.User, repo *repo_model.Repository)
 	NotifyPackageCreate(ctx context.Context, doer *user_model.User, pd *packages_model.PackageDescriptor)
 	NotifyPackageDelete(ctx context.Context, doer *user_model.User, pd *packages_model.PackageDescriptor)
+	NotifyNewUserSignUp(ctx context.Context, newUser *user_model.User)
 }

modules/notification/base/null.go

@@ -204,3 +204,7 @@ func (*NullNotifier) NotifyPackageCreate(ctx context.Context, doer *user_model.U
 // NotifyPackageDelete places a place holder function
 func (*NullNotifier) NotifyPackageDelete(ctx context.Context, doer *user_model.User, pd *packages_model.PackageDescriptor) {
 }
+
+// NotifyNewUserSignUp notifies deletion of a package to notifiers
+func (*NullNotifier) NotifyNewUserSignUp(ctx context.Context, newUser *user_model.User) {
+}

modules/notification/mail/mail.go

@@ -200,3 +200,7 @@ func (m *mailNotifier) NotifyRepoPendingTransfer(ctx context.Context, doer, newO
 		log.Error("SendRepoTransferNotifyMail: %v", err)
 	}
 }
+
+func (m *mailNotifier) NotifyNewUserSignUp(ctx context.Context, newUser *user_model.User) {
+	mailer.MailNewUser(ctx, newUser)
+}

modules/notification/notification.go

@@ -376,3 +376,10 @@ func NotifyPackageDelete(ctx context.Context, doer *user_model.User, pd *package
 		notifier.NotifyPackageDelete(ctx, doer, pd)
 	}
 }
+
+// NotifyNewUserSignUp notifies deletion of a package to notifiers
+func NotifyNewUserSignUp(ctx context.Context, newUser *user_model.User) {
+	for _, notifier := range notifiers {
+		notifier.NotifyNewUserSignUp(ctx, newUser)
+	}
+}

modules/setting/admin.go

@@ -7,6 +7,7 @@ package setting
 var Admin struct {
 	DisableRegularOrgCreation bool
 	DefaultEmailNotification  string
+	NotifyNewSignUps          bool
 }
 
 func loadAdminFrom(rootCfg ConfigProvider) {

options/locale/locale_en-US.ini

@@ -438,6 +438,10 @@ activate_email = Verify your email address
 activate_email.title = %s, please verify your email address
 activate_email.text = Please click the following link to verify your email address within <b>%s</b>:
 
+admin.new_user.subject = New user %s
+admin.new_user.user_info = User Information
+admin.new_user.text = Please <a href="%s">click here</a> to manage the user from the admin panel.
+
 register_notify = Welcome to Gitea
 register_notify.title = %[1]s, welcome to %[2]s
 register_notify.text_1 = this is your registration confirmation email for %s!

routers/web/auth/auth.go

@@ -18,6 +18,7 @@ import (
 	"code.gitea.io/gitea/modules/context"
 	"code.gitea.io/gitea/modules/eventsource"
 	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/notification"
 	"code.gitea.io/gitea/modules/session"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/timeutil"
@@ -568,6 +569,7 @@ func handleUserCreated(ctx *context.Context, u *user_model.User, gothUser *goth.
 		}
 	}
 
+	notification.NotifyNewUserSignUp(ctx, u)
 	// update external user information
 	if gothUser != nil {
 		if err := externalaccount.UpdateExternalUser(u, *gothUser); err != nil {
@@ -591,7 +593,6 @@ func handleUserCreated(ctx *context.Context, u *user_model.User, gothUser *goth.
 		ctx.Data["Email"] = u.Email
 		ctx.Data["ActiveCodeLives"] = timeutil.MinutesToFriendly(setting.Service.ActiveCodeLives, ctx.Locale)
 		ctx.HTML(http.StatusOK, TplActivate)
-
 		if setting.CacheService.Enabled {
 			if err := ctx.Cache.Put("MailResendLimit_"+u.LowerName, u.LowerName, 180); err != nil {
 				log.Error("Set cache(MailResendLimit) fail: %v", err)

services/mailer/mail_admin_new_user.go

@@ -0,0 +1,82 @@
+// Copyright 2023 The Forgejo Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+package mailer
+
+import (
+	"bytes"
+	"context"
+	"strconv"
+
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/base"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/templates"
+	"code.gitea.io/gitea/modules/translation"
+)
+
+const (
+	tplNewUserMail base.TplName = "admin_new_user"
+)
+
+var sa = SendAsyncs
+
+// MailNewUser sends notification emails on new user registrations to all admins
+func MailNewUser(ctx context.Context, u *user_model.User) {
+	if !setting.Admin.NotifyNewSignUps {
+		return
+	}
+
+	if setting.MailService == nil {
+		// No mail service configured
+		return
+	}
+
+	recipients, err := user_model.GetAllUsers()
+	if err != nil {
+		log.Error("user_model.GetAllUsers: %v", err)
+		return
+	}
+
+	langMap := make(map[string][]string)
+	for _, r := range recipients {
+		if r.IsAdmin {
+			langMap[r.Language] = append(langMap[r.Language], r.Email)
+		}
+	}
+
+	for lang, tos := range langMap {
+		mailNewUser(ctx, u, lang, tos)
+	}
+}
+
+func mailNewUser(ctx context.Context, u *user_model.User, lang string, tos []string) {
+	locale := translation.NewLocale(lang)
+
+	subject := locale.Tr("mail.admin.new_user.subject", u.Name)
+	manageUserURL := setting.AppSubURL + "/admin/users/" + strconv.FormatInt(u.ID, 10)
+	body := locale.Tr("mail.admin.new_user.text", manageUserURL)
+	mailMeta := map[string]any{
+		"NewUser":  u,
+		"Subject":  subject,
+		"Body":     body,
+		"Language": locale.Language(),
+		"locale":   locale,
+		"Str2html": templates.Str2html,
+	}
+
+	var mailBody bytes.Buffer
+
+	if err := bodyTemplates.ExecuteTemplate(&mailBody, string(tplNewUserMail), mailMeta); err != nil {
+		log.Error("ExecuteTemplate [%s]: %v", string(tplNewUserMail)+"/body", err)
+		return
+	}
+
+	msgs := make([]*Message, 0, len(tos))
+	for _, to := range tos {
+		msg := NewMessage(to, subject, mailBody.String())
+		msg.Info = subject
+		msgs = append(msgs, msg)
+	}
+	sa(msgs)
+}

services/mailer/mail_admin_new_user_test.go

@@ -0,0 +1,88 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package mailer
+
+import (
+	"context"
+	"strconv"
+	"strings"
+	"testing"
+
+	"code.gitea.io/gitea/models/db"
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/setting"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func getTestUsers() []*user_model.User {
+	admin := new(user_model.User)
+	admin.Name = "admin"
+	admin.IsAdmin = true
+	admin.Language = "en_US"
+	admin.Email = "admin@forgejo.org"
+
+	newUser := new(user_model.User)
+	newUser.Name = "new_user"
+	newUser.Language = "en_US"
+	newUser.IsAdmin = false
+	newUser.Email = "new_user@forgejo.org"
+	newUser.LastLoginUnix = 1693648327
+	newUser.CreatedUnix = 1693648027
+
+	user_model.CreateUser(admin)
+	user_model.CreateUser(newUser)
+
+	users := make([]*user_model.User, 0)
+	users = append(users, admin)
+	users = append(users, newUser)
+
+	return users
+}
+
+func cleanUpUsers(ctx context.Context, users []*user_model.User) {
+	for _, u := range users {
+		db.DeleteByID(ctx, u.ID, new(user_model.User))
+	}
+}
+
+func TestAdminNotificationMail_test(t *testing.T) {
+	mailService := setting.Mailer{
+		From:     "test@forgejo.org",
+		Protocol: "dummy",
+	}
+
+	setting.MailService = &mailService
+	setting.Domain = "localhost"
+	setting.AppSubURL = "http://localhost"
+
+	// test with NOTIFY_NEW_SIGNUPS enabled
+	setting.Admin.NotifyNewSignUps = true
+
+	ctx := context.Background()
+	NewContext(ctx)
+
+	users := getTestUsers()
+	oldSendAsyncs := sa
+	defer func() {
+		sa = oldSendAsyncs
+		cleanUpUsers(ctx, users)
+	}()
+
+	sa = func(msgs []*Message) {
+		assert.Equal(t, len(msgs), 1, "Test provides only one admin user, so only one email must be sent")
+		assert.Equal(t, msgs[0].To, users[0].Email, "checks if the recipient is the admin of the instance")
+		manageUserURL := "/admin/users/" + strconv.FormatInt(users[1].ID, 10)
+		assert.True(t, strings.ContainsAny(msgs[0].Body, manageUserURL), "checks if the message contains the link to manage the newly created user from the admin panel")
+	}
+	MailNewUser(ctx, users[1])
+
+	// test with NOTIFY_NEW_SIGNUPS disabled; emails shouldn't be sent
+	setting.Admin.NotifyNewSignUps = false
+	sa = func(msgs []*Message) {
+		assert.Equal(t, 1, 0, "this shouldn't execute. MailNewUser must exit early since NOTIFY_NEW_SIGNUPS is disabled")
+	}
+
+	MailNewUser(ctx, users[1])
+}

templates/mail/admin_new_user.tmpl

@@ -0,0 +1,22 @@
+<!DOCTYPE html>
+<html>
+<head>
+	<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
+	<title>{{.Subject}}</title>
+
+	<style>
+		blockquote { padding-left: 1em; margin: 1em 0; border-left: 1px solid grey; color: #777}
+		.footer { font-size:small; color:#666;}
+	</style>
+
+</head>
+
+<body>
+	<ul>
+		<h3>{{.locale.Tr "mail.admin.new_user.user_info"}}</h3>
+		<li>{{.locale.Tr "admin.users.created"}}: {{DateTime "full" .NewUser.LastLoginUnix}}</li>
+		<li>{{.locale.Tr "admin.users.last_login"}}: {{DateTime "full" .NewUser.CreatedUnix}}</li>
+	</ul>
+	<p> {{.Body | Str2html}} </p>
+</body>
+</html>