emails: Add one-click unsubscribe link to new login emails.

Fixes: #10547.

templates/zerver/emails/notify_new_login.source.html

@@ -23,3 +23,7 @@ Server: {{ realm_uri }} Account: {{ user_email }} Time: {{ login_time }}
 <p>If you recognize this login activity, you can archive this notice.</p>
 <p>Thanks,<br />Zulip Account Security</p>
 {% endblock %}
+
+{% block manage_preferences %}
+<p><a href="{{ realm_uri }}/#settings/notifications">Manage email preferences</a> | <a href="{{ unsubscribe_link }}">Unsubscribe from login notifications</a></p>
+{% endblock %}

zerver/signals.py

@@ -10,6 +10,7 @@ from django.utils.timezone import \
 from django.utils.timezone import now as timezone_now
 from django.utils.translation import ugettext_lazy as _
 
+from confirmation.models import one_click_unsubscribe_link
 from zerver.lib.queue import queue_json_publish
 from zerver.lib.send_email import FromAddress
 from zerver.models import UserProfile
@@ -91,6 +92,7 @@ def email_on_new_login(sender: Any, user: UserProfile, request: Any, **kwargs: A
         context['device_ip'] = request.META.get('REMOTE_ADDR') or _("Unknown IP address")
         context['device_os'] = get_device_os(user_agent)
         context['device_browser'] = get_device_browser(user_agent)
+        context['unsubscribe_link'] = one_click_unsubscribe_link(user, 'login')
 
         email_dict = {
             'template_prefix': 'zerver/emails/notify_new_login',

zerver/tests/test_signup.py

@@ -1568,6 +1568,24 @@ class EmailUnsubscribeTests(ZulipTestCase):
         self.assertFalse(user_profile.enable_digest_emails)
         self.assertEqual(0, ScheduledEmail.objects.filter(user=user_profile).count())
 
+    def test_login_unsubscribe(self) -> None:
+        """
+        We provide one-click unsubscribe links in login
+        e-mails that you can click even when logged out to update your
+        email notification settings.
+        """
+        user_profile = self.example_user('hamlet')
+        user_profile.enable_login_emails = True
+        user_profile.save()
+
+        unsubscribe_link = one_click_unsubscribe_link(user_profile, "login")
+        result = self.client_get(urllib.parse.urlparse(unsubscribe_link).path)
+
+        self.assertEqual(result.status_code, 200)
+
+        user_profile.refresh_from_db()
+        self.assertFalse(user_profile.enable_login_emails)
+
 class RealmCreationTest(ZulipTestCase):
     @override_settings(OPEN_REALM_CREATION=True)
     def check_able_to_create_realm(self, email: str) -> None:

zerver/views/unsubscribe.py

@@ -34,6 +34,9 @@ def do_welcome_unsubscribe(user_profile: UserProfile) -> None:
 def do_digest_unsubscribe(user_profile: UserProfile) -> None:
     do_change_notification_settings(user_profile, 'enable_digest_emails', False)
 
+def do_login_unsubscribe(user_profile: UserProfile) -> None:
+    do_change_notification_settings(user_profile, 'enable_login_emails', False)
+
 # The keys are part of the URL for the unsubscribe link and must be valid
 # without encoding.
 # The values are a tuple of (display name, unsubscribe function), where the
@@ -41,7 +44,8 @@ def do_digest_unsubscribe(user_profile: UserProfile) -> None:
 email_unsubscribers = {
     "missed_messages": ("missed messages", do_missedmessage_unsubscribe),
     "welcome": ("welcome", do_welcome_unsubscribe),
-    "digest": ("digest", do_digest_unsubscribe)
+    "digest": ("digest", do_digest_unsubscribe),
+    "login": ("login", do_login_unsubscribe)
 }
 
 # Login NOT required. These are for one-click unsubscribes.