email: Fix zephyr mirror registration email not working with subdomains.

If a user is trying to register for a mit zephyr mirroring realm, we send
them a specific registration email with a link to a few more instructions.

There is only one server that we know about that has such a realm, and that
server uses subdomains. This commit changes the logic to work in the
subdomains case, rather than in the non-subdomains case (though see next
para).

Note that the current check is deceptive, and is not actually correct in the
non-subdomains case. The prereg user has a realm only in the atypical case
of someone registering via the special URL for completely-open realms.

To do this correctly in the non-subdomains case, we would need to copy a
bunch of the logic from the beginning of accounts_register to figure out
which realm the user is signing up for, so that we can check if that realm
is a zephyr mirroring realm. Given how complicated the registration code is
already, I think it is probably not worth it at the moment. This commit also
removes the partial (deceptive) check, since I think it does more harm than
good.

zerver/tests/test_signup.py

@@ -18,8 +18,8 @@ from zilencer.models import Deployment
 from zerver.forms import HomepageForm, WRONG_SUBDOMAIN_ERROR
 from zerver.lib.actions import do_change_password
 from zerver.views.invite import get_invitee_emails_set
-from zerver.views.registration import (confirmation_key,
-                                       redirect_and_log_into_subdomain)
+from zerver.views.registration import confirmation_key, \
+    redirect_and_log_into_subdomain, send_registration_completion_email
 from zerver.models import (
     get_realm, get_prereg_user_by_email, get_user_profile_by_email,
     get_unique_open_realm, completely_open,
@@ -1463,6 +1463,32 @@ class UserSignUpTest(ZulipTestCase):
         mock_ldap.reset()
         mock_initialize.stop()
 
+    def test_registration_email_for_mirror_dummy_user(self):
+        # type: () -> None
+        email = 'sipbtest@mit.edu'
+
+        user_profile = get_user_profile_by_email(email)
+        user_profile.is_mirror_dummy = True
+        user_profile.is_active = False
+        user_profile.save()
+
+        with self.settings(REALMS_HAVE_SUBDOMAINS=True):
+            with patch('zerver.forms.get_subdomain', return_value='zephyr'):
+                with patch('zerver.views.registration.get_subdomain', return_value='zephyr'):
+                    result = self.client_post('/accounts/home/', {'email': email})
+                    self.assertEqual(result.status_code, 302)
+
+        from django.core.mail import outbox
+        for message in reversed(outbox):
+            if email in message.to:
+                # The main difference between the zephyr registation email
+                # and the normal one is this string
+                index = message.body.find('https://zephyr.zulipchat.com/zephyr')
+                if index >= 0:
+                    return
+        else:
+            raise AssertionError("Couldn't find the right confirmation email.")
+
     @patch('DNS.dnslookup', return_value=[['sipbtest:*:20922:101:Fred Sipb,,,:/mit/sipbtest:/bin/athena/tcsh']])
     def test_registration_of_mirror_dummy_user(self, ignored):
         # type: (Any) -> None

zerver/views/registration.py

@@ -287,8 +287,14 @@ def send_registration_completion_email(email, request, realm_creation=False):
     can complete their registration.
     """
     template_prefix = 'confirmation/preregistrationuser_confirmation_email'
-    if prereg_user.realm and prereg_user.realm.is_zephyr_mirror_realm: # nocoverage, see next commit
-        template_prefix = 'confirmation/mituser_confirmation_email' # nocoverage, see next commit
+    # Note: to make the following work in the non-subdomains case, you'll
+    # need to copy the logic from the beginning of accounts_register to
+    # figure out which realm the user is trying to sign up for, and then
+    # check if it is a zephyr mirror realm.
+    if settings.REALMS_HAVE_SUBDOMAINS:
+        realm = get_realm(get_subdomain(request))
+        if realm and realm.is_zephyr_mirror_realm:
+            template_prefix = 'confirmation/mituser_confirmation_email'
 
     prereg_user = create_preregistration_user(email, request, realm_creation)
     context = {'support_email': settings.ZULIP_ADMINISTRATOR,