Fix: join form endpoint crashes due to custom serializer bug

src/meshapi/serializers/nested_key_object_related_field.py

@@ -1,5 +1,6 @@
 import typing
 from typing import Any, Dict, Tuple, cast
+from uuid import UUID
 
 from django.core.exceptions import ObjectDoesNotExist
 from django.db.models import Model
@@ -42,7 +43,16 @@ def _get_key_fields(self) -> Tuple[str, ...]:
         return ("id",) + self.additional_keys
 
     def to_representation(self, value: Model) -> dict[str, Any]:
-        return {key: getattr(value, key) for key in self._get_key_fields()}
+        output = {}
+        for key in self._get_key_fields():
+            output[key] = getattr(value, key)
+
+            # Convert UUID objects to str so that the resulting data
+            # is trivially JSON serializable
+            if isinstance(output[key], UUID):
+                output[key] = str(output[key])
+
+        return output
 
     def to_internal_value(self, data: dict) -> Model:
         queryset = self.get_queryset()

src/meshapi/tests/test_slack_notification.py

@@ -6,12 +6,26 @@
 from django.test import RequestFactory, TestCase
 from requests import RequestException
 
-from meshapi.models import Member
+from meshapi.models import Building, Install, Member
 from meshapi.serializers import MemberSerializer
+from meshapi.tests.sample_data import sample_building, sample_install, sample_member
 from meshapi.util.admin_notifications import notify_administrators_of_data_issue
 
 
 class TestSlackNotification(TestCase):
+    def setUp(self):
+        self.sample_install_copy = sample_install.copy()
+        self.building_1 = Building(**sample_building)
+        self.building_1.save()
+        self.sample_install_copy["building"] = self.building_1
+
+        self.sample_member = Member(**sample_member)
+        self.sample_member.save()
+        self.sample_install_copy["member"] = self.sample_member
+
+        self.install = Install(**self.sample_install_copy)
+        self.install.save()
+
     @requests_mock.Mocker()
     @patch("meshapi.util.admin_notifications.SLACK_ADMIN_NOTIFICATIONS_WEBHOOK_URL", "https://mock-slack-url")
     def test_slack_notification_for_name_change(self, requests_mocker):
@@ -23,6 +37,9 @@ def test_slack_notification_for_name_change(self, requests_mocker):
         )
         member.save()
 
+        self.install.member = member
+        self.install.save()
+
         rf = RequestFactory()
         mock_join_form_request = rf.post("https://mock-meshdb-url.example/join-form/")
 
@@ -56,7 +73,12 @@ def test_slack_notification_for_name_change(self, requests_mocker):
             '    "all_phone_numbers": [\n'
             '      "+1 212-555-5555"\n'
             "    ],\n"
-            '    "installs": [],\n'
+            '    "installs": [\n'
+            "      {\n"
+            f'        "id": "{self.install.id}",\n'
+            f'        "install_number": {self.install.install_number}\n'
+            "      }\n"
+            "    ],\n"
             '    "name": "Stacy Maidenname",\n'
             '    "primary_email_address": "[email protected]",\n'
             '    "stripe_email_address": null,\n'