Notify new user if their email domain matches existing Perma partner(…

…s) (#3596)

* Initial pass at user email/registrar domain match function

* Implement basic suggested registrars test and fix existing tests

* Use SQL regex pattern to check hostname match

* Support multiple suggested registrars; fix mutable default arg bug

* Fix suggest_registrars so it ignores path after base domain

perma_web/perma/templates/email/includes/activation.txt

@@ -1,6 +1,10 @@
 In order to complete your account activation, please confirm your email address and set a password. It’s as simple as clicking the link below. The link will be valid for the next {% widthratio activation_expires 3600 1 %} hours.
 
-{{ activation_route }}
+    {{ activation_route }}
+
+{% if suggested_registrars %}Note: We’ve also found {% if suggested_registrars|length == 1 %}a Perma.cc partner institution{% else %}some Perma.cc partner institutions{% endif %} with whom you might be affiliated. You may be able to request a sponsored account by contacting them:
+{% for suggested_registrar in suggested_registrars %}
+  - {{ suggested_registrar.name }}: {{ suggested_registrar.email }}{% endfor %}{% endif %}
 
 Thanks,
 The Perma.cc Team

perma_web/perma/tests/test_views_user_management.py

@@ -2585,7 +2585,9 @@ def check_new_activation_email(self, message, user_email):
         self.assertEqual(message.from_email, settings.DEFAULT_FROM_EMAIL)
         self.assertEqual(message.recipients(), [user_email])
 
-        activation_url = next(line for line in message.body.rstrip().split("\n") if line.startswith('http'))
+        activation_url = next(
+            line for line in message.body.rstrip().split('\n') if line.strip().startswith('http')
+        )
         return activation_url
 
     @override_settings(REQUIRE_JS_FORM_SUBMISSIONS=False)
@@ -2637,6 +2639,31 @@ def test_account_creation_views(self):
         response = self.client.post(reverse('user_management_limited_login'), {'username': new_user_raw_email, 'password': 'Anewpass1'}, follow=True, secure=True)
         self.assertContains(response, 'Enter any URL to preserve it forever')
 
+    @override_settings(REQUIRE_JS_FORM_SUBMISSIONS=False)
+    def test_suggested_registrars(self):
+        # Register user
+        _, registrar_domain = self.registrar.email.split('@')
+        new_user_email = f'new_user@{registrar_domain}'
+        self.submit_form(
+            'sign_up',
+            {'e-address': new_user_email, 'first_name': 'Test', 'last_name': 'Test'},
+            success_url=reverse('register_email_instructions'),
+            success_query=LinkUser.objects.filter(email=new_user_email),
+        )
+        self.assertEqual(len(mail.outbox), 1)
+
+        # Obtain suggested registrar(s) from activation email message
+        message = mail.outbox[0]
+        lines = message.body.splitlines()
+        captures = []
+        for line in lines:
+            if line.lstrip().startswith('- '):
+                captures.append(line.strip('- '))
+
+        # Validate suggested registrar(s)
+        self.assertEqual(len(captures), 1)
+        self.assertEqual(captures[0], f'{self.registrar.name}: {self.registrar.email}')
+
     @override_settings(REQUIRE_JS_FORM_SUBMISSIONS=False)
     def test_signup_with_existing_email_rejected(self):
         self.assertEqual(LinkUser.objects.filter(email__iexact=self.registrar_user.email).count(), 1)

perma_web/perma/views/user_management.py

@@ -2,6 +2,7 @@
 from datetime import timedelta
 import itertools
 import logging
+import re
 from typing import Literal
 
 import celery
@@ -1988,7 +1989,26 @@ def firm_request_response(request):
     return render(request, 'registration/firm_request.html')
 
 
-def email_new_user(request, user, template="email/new_user.txt", context={}):
+def suggest_registrars(user: LinkUser, limit: int = 5) -> BaseManager[Registrar]:
+    """Suggest potential registrars for a user based on email domain.
+
+    This queries the database for registrars whose website matches the
+    base domain from the user's email address. For example, if the
+    user's email is `[email protected]`, this will suggest
+    registrars whose domains end with `harvard.edu`.
+    """
+    _, email_domain = user.email.split('@')
+    base_domain = '.'.join(email_domain.rsplit('.', 2)[-2:])
+    pattern = f'^https?://([a-zA-Z0-9\\-\\.]+\\.)?{re.escape(base_domain)}(/.*)?$'
+    registrars = (
+        Registrar.objects.exclude(status='pending')
+        .filter(website__iregex=pattern)
+        .order_by('-link_count', 'name')[:limit]
+    )
+    return registrars
+
+
+def email_new_user(request, user, template='email/new_user.txt', context=None):
     """
     Send email to newly created accounts
     """
@@ -1997,11 +2017,20 @@ def email_new_user(request, user, template="email/new_user.txt", context={}):
         urlsafe_base64_encode(force_bytes(user.pk)),
         default_token_generator.make_token(user),
     ]))
-    context.update({
-        'activation_route': activation_route,
-        'activation_expires': settings.PASSWORD_RESET_TIMEOUT,
-        'request': request
-    })
+
+    # Include context variables
+    template_is_default = template == 'email/new_user.txt'
+    context = context if context is not None else {}
+    context.update(
+        {
+            'activation_expires': settings.PASSWORD_RESET_TIMEOUT,
+            'activation_route': activation_route,
+            'request': request,
+            # Only query DB if we're using the default template; otherwise there's no need
+            'suggested_registrars': suggest_registrars(user) if template_is_default else [],
+        }
+    )
+
     send_user_email(
         user.raw_email,
         template,