6 files changed, 195 insertions, 0 deletions

diff --git a/services/mailer/mail_admin_new_user.go b/services/mailer/mail_admin_new_user.go
new file mode 100644
index 0000000000..e9610e626a
--- /dev/null
+++ b/services/mailer/mail_admin_new_user.go
@@ -0,0 +1,81 @@
+// 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 = "notify/admin_new_user"
+)
+
+var sa = SendAsync
+
+// MailNewUser sends notification emails on new user registrations to all admins
+func MailNewUser(ctx context.Context, u *user_model.User) {
+	if !setting.Admin.SendNotificationEmailOnNewUser {
+		return
+	}
+
+	if setting.MailService == nil {
+		// No mail service configured
+		return
+	}
+
+	recipients, err := user_model.GetAllAdmins(ctx)
+	if err != nil {
+		log.Error("user_model.GetAllAdmins: %v", err)
+		return
+	}
+
+	langMap := make(map[string][]string)
+	for _, r := range recipients {
+		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)
+
+	manageUserURL := setting.AppURL + "admin/users/" + strconv.FormatInt(u.ID, 10)
+	subject := locale.Tr("mail.admin.new_user.subject", u.Name)
+	body := locale.Tr("mail.admin.new_user.text", manageUserURL)
+	mailMeta := map[string]any{
+		"NewUser":    u,
+		"NewUserUrl": u.HTMLURL(),
+		"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...)
+}
diff --git a/services/mailer/mail_admin_new_user_test.go b/services/mailer/mail_admin_new_user_test.go
new file mode 100644
index 0000000000..b89d888ee1
--- /dev/null
+++ b/services/mailer/mail_admin_new_user_test.go
@@ -0,0 +1,98 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package mailer
+
+import (
+	"context"
+	"strconv"
+	"testing"
+
+	"code.gitea.io/gitea/models/db"
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/translation"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func getTestUsers(t *testing.T) []*user_model.User {
+	t.Helper()
+	admin := new(user_model.User)
+	admin.Name = "testadmin"
+	admin.IsAdmin = true
+	admin.Language = "en_US"
+	admin.Email = "admin@example.com"
+	require.NoError(t, user_model.CreateUser(db.DefaultContext, admin))
+
+	newUser := new(user_model.User)
+	newUser.Name = "new_user"
+	newUser.Language = "en_US"
+	newUser.IsAdmin = false
+	newUser.Email = "new_user@example.com"
+	newUser.LastLoginUnix = 1693648327
+	newUser.CreatedUnix = 1693648027
+	require.NoError(t, user_model.CreateUser(db.DefaultContext, newUser))
+
+	return []*user_model.User{admin, newUser}
+}
+
+func cleanUpUsers(ctx context.Context, users []*user_model.User) {
+	for _, u := range users {
+		db.DeleteByID[user_model.User](ctx, u.ID)
+	}
+}
+
+func TestAdminNotificationMail_test(t *testing.T) {
+	translation.InitLocales(context.Background())
+	locale := translation.NewLocale("")
+	key := "mail.admin.new_user.user_info"
+	translatedKey := locale.Tr(key)
+	require.NotEqualValues(t, key, translatedKey)
+
+	mailService := setting.Mailer{
+		From:     "test@example.com",
+		Protocol: "dummy",
+	}
+
+	setting.MailService = &mailService
+
+	// test with SEND_NOTIFICATION_EMAIL_ON_NEW_USER enabled
+	setting.Admin.SendNotificationEmailOnNewUser = true
+
+	ctx := context.Background()
+	NewContext(ctx)
+
+	users := getTestUsers(t)
+	oldSendAsync := sa
+	defer func() {
+		sa = oldSendAsync
+		cleanUpUsers(ctx, users)
+	}()
+
+	called := false
+	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 := setting.AppURL + "admin/users/" + strconv.FormatInt(users[1].ID, 10)
+		assert.Contains(t, msgs[0].Body, manageUserURL)
+		assert.Contains(t, msgs[0].Body, users[1].HTMLURL())
+		assert.Contains(t, msgs[0].Body, translatedKey, "the .Locale translates to nothing")
+		assert.Contains(t, msgs[0].Body, users[1].Name, "user name of the newly created user")
+		for _, untranslated := range []string{"mail.admin", "admin.users"} {
+			assert.NotContains(t, msgs[0].Body, untranslated, "this is an untranslated placeholder prefix")
+		}
+		called = true
+	}
+	MailNewUser(ctx, users[1])
+	assert.True(t, called)
+
+	// test with SEND_NOTIFICATION_EMAIL_ON_NEW_USER disabled; emails shouldn't be sent
+	setting.Admin.SendNotificationEmailOnNewUser = false
+	sa = func(msgs ...*Message) {
+		assert.Equal(t, 1, 0, "this shouldn't execute. MailNewUser must exit early since SEND_NOTIFICATION_EMAIL_ON_NEW_USER is disabled")
+	}
+
+	MailNewUser(ctx, users[1])
+}
diff --git a/services/mailer/notify.go b/services/mailer/notify.go
index e48b5d399d..54ab80aab9 100644
--- a/services/mailer/notify.go
+++ b/services/mailer/notify.go
@@ -202,3 +202,7 @@ func (m *mailNotifier) RepoPendingTransfer(ctx context.Context, doer, newOwner *
 		log.Error("SendRepoTransferNotifyMail: %v", err)
 	}
 }
+
+func (m *mailNotifier) NewUserSignUp(ctx context.Context, newUser *user_model.User) {
+	MailNewUser(ctx, newUser)
+}
diff --git a/services/notify/notifier.go b/services/notify/notifier.go
index ed053a812a..3230a5e5f5 100644
--- a/services/notify/notifier.go
+++ b/services/notify/notifier.go
@@ -59,6 +59,8 @@ type Notifier interface {
 	EditWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model.Repository, page, comment string)
 	DeleteWikiPage(ctx context.Context, doer *user_model.User, repo *repo_model.Repository, page string)
 
+	NewUserSignUp(ctx context.Context, newUser *user_model.User)
+
 	NewRelease(ctx context.Context, rel *repo_model.Release)
 	UpdateRelease(ctx context.Context, doer *user_model.User, rel *repo_model.Release)
 	DeleteRelease(ctx context.Context, doer *user_model.User, rel *repo_model.Release)
diff --git a/services/notify/notify.go b/services/notify/notify.go
index 16fbb6325d..9cb329d302 100644
--- a/services/notify/notify.go
+++ b/services/notify/notify.go
@@ -347,6 +347,13 @@ func RepoPendingTransfer(ctx context.Context, doer, newOwner *user_model.User, r
 	}
 }
 
+// NewUserSignUp notifies about a newly signed up user to notifiers
+func NewUserSignUp(ctx context.Context, newUser *user_model.User) {
+	for _, notifier := range notifiers {
+		notifier.NewUserSignUp(ctx, newUser)
+	}
+}
+
 // PackageCreate notifies creation of a package to notifiers
 func PackageCreate(ctx context.Context, doer *user_model.User, pd *packages_model.PackageDescriptor) {
 	for _, notifier := range notifiers {
diff --git a/services/notify/null.go b/services/notify/null.go
index dddd421bef..894d118eac 100644
--- a/services/notify/null.go
+++ b/services/notify/null.go
@@ -197,6 +197,9 @@ func (*NullNotifier) SyncDeleteRef(ctx context.Context, doer *user_model.User, r
 func (*NullNotifier) RepoPendingTransfer(ctx context.Context, doer, newOwner *user_model.User, repo *repo_model.Repository) {
 }
 
+func (*NullNotifier) NewUserSignUp(ctx context.Context, newUser *user_model.User) {
+}
+
 // PackageCreate places a place holder function
 func (*NullNotifier) PackageCreate(ctx context.Context, doer *user_model.User, pd *packages_model.PackageDescriptor) {
 }