From 6453910fffea3e4ac12bb2facafa5784d2755ee5 Mon Sep 17 00:00:00 2001
From: Matt Cottingham <mattcottingham@monzo.com>
Date: Fri, 1 Nov 2019 14:56:15 +0000
Subject: [PATCH 1/7] Initial events API implementation

---
 response/apps.py                 |  2 ++
 response/core/admin.py           |  3 ++-
 response/core/models/__init__.py |  2 ++
 response/core/models/event.py    | 12 +++++++++
 response/core/serializers.py     | 10 +++++++-
 response/core/signals.py         | 42 ++++++++++++++++++++++++++++++++
 response/core/urls.py            |  2 ++
 response/core/views.py           |  6 +++++
 response/models.py               | 10 +++++++-
 response/serializers.py          |  6 +++--
 10 files changed, 90 insertions(+), 5 deletions(-)
 create mode 100644 response/core/models/event.py
 create mode 100644 response/core/signals.py

diff --git a/response/apps.py b/response/apps.py
index 61637925..a82a4f2b 100644
--- a/response/apps.py
+++ b/response/apps.py
@@ -16,6 +16,8 @@ def ready(self):
             dialog_handlers,
         )
 
+        from .core import signals
+
         site_settings.RESPONSE_LOGIN_REQUIRED = getattr(
             site_settings, "RESPONSE_LOGIN_REQUIRED", True
         )
diff --git a/response/core/admin.py b/response/core/admin.py
index 55b92acf..5755ac97 100644
--- a/response/core/admin.py
+++ b/response/core/admin.py
@@ -1,7 +1,8 @@
 from django.contrib import admin
 
-from response.core.models import Action, ExternalUser, Incident
+from response.core.models import Action, Event, ExternalUser, Incident
 
 admin.site.register(Action)
+admin.site.register(Event)
 admin.site.register(Incident)
 admin.site.register(ExternalUser)
diff --git a/response/core/models/__init__.py b/response/core/models/__init__.py
index ff4959b8..91b49d1e 100644
--- a/response/core/models/__init__.py
+++ b/response/core/models/__init__.py
@@ -1,10 +1,12 @@
 from .action import Action
 from .incident import Incident
 from .timeline import TimelineEvent, add_incident_update_event
+from .event import Event
 from .user_external import ExternalUser
 
 __all__ = (
     "Action",
+    "Event",
     "Incident",
     "TimelineEvent",
     "ExternalUser",
diff --git a/response/core/models/event.py b/response/core/models/event.py
new file mode 100644
index 00000000..d84dfcd3
--- /dev/null
+++ b/response/core/models/event.py
@@ -0,0 +1,12 @@
+from django.contrib.postgres.fields import JSONField
+
+from django.db import models
+
+
+class Event(models.Model):
+    ACTION_EVENT_TYPE= "action_event"
+    INCIDENT_EVENT_TYPE = "incident_event"
+
+    timestamp = models.DateTimeField()
+    event_type = models.CharField(max_length=50)
+    payload = JSONField()
diff --git a/response/core/serializers.py b/response/core/serializers.py
index a2e7f795..f451f0f1 100644
--- a/response/core/serializers.py
+++ b/response/core/serializers.py
@@ -1,7 +1,7 @@
 import emoji_data_python
 from rest_framework import serializers
 
-from response.core.models import Action, ExternalUser, Incident, TimelineEvent
+from response.core.models import Action, Event, ExternalUser, Incident, TimelineEvent
 from response.slack.models import CommsChannel
 from response.slack.reference_utils import slack_to_human_readable
 
@@ -131,3 +131,11 @@ def update(self, instance, validated_data):
 
         instance.save()
         return instance
+
+
+class EventSerializer(serializers.ModelSerializer):
+
+    class Meta:
+        model = Event
+        fields = ("id", "timestamp", "event_type", "payload")
+        read_only_fields = ("id", "timestamp", "event_type", "payload")
diff --git a/response/core/signals.py b/response/core/signals.py
new file mode 100644
index 00000000..e13565b8
--- /dev/null
+++ b/response/core/signals.py
@@ -0,0 +1,42 @@
+from datetime import datetime
+
+from response.core.models import Action, Event, Incident
+from response.core.serializers import ActionSerializer, IncidentSerializer
+
+from django.db.models.signals import post_save
+from django.dispatch import receiver
+
+import logging
+logger = logging.getLogger(__name__)
+
+
+@receiver(post_save, sender=Action)
+def emit_action_event(sender, instance: Action, **kwargs):
+    logger.info(f"Handling post_save for action: {instance}")
+
+    event = Event()
+    event.event_type = Event.ACTION_EVENT_TYPE
+
+    # Event payload should be a dict for serializing to JSON.
+    event.payload = ActionSerializer(instance).data
+    event.payload["incident_id"] = instance.incident.pk
+    # TODO: define a serializer that elides this field (otherwise
+    # it is returned in incident responses too)
+    if "details_ui" in event.payload: del event.payload["details_ui"]
+
+    event.timestamp = datetime.now(tz=None)
+    event.save()
+
+
+@receiver(post_save, sender=Incident)
+def emit_incident_event(sender, instance: Incident, **kwargs):
+    logger.info(f"Handling post_save for incident: {instance}")
+
+    event = Event()
+    event.event_type = Event.INCIDENT_EVENT_TYPE
+
+    # Event payload should be a dict for serializing to JSON.
+    event.payload = IncidentSerializer(instance).data
+
+    event.timestamp = datetime.now(tz=None)
+    event.save()
diff --git a/response/core/urls.py b/response/core/urls.py
index 678141f1..bd7e5ff7 100644
--- a/response/core/urls.py
+++ b/response/core/urls.py
@@ -3,6 +3,7 @@
 
 from response.core.views import (
     ActionViewSet,
+    EventsViewSet,
     ExternalUserViewSet,
     IncidentActionViewSet,
     IncidentsByMonthViewSet,
@@ -30,6 +31,7 @@
 )
 router.register(r"actions", ActionViewSet)
 router.register(r"users", ExternalUserViewSet)
+router.register(r"events", EventsViewSet)
 
 # Wire up our API using automatic URL routing.
 # Additionally, we include login URLs for the browsable API.
diff --git a/response/core/views.py b/response/core/views.py
index 0a0cfde4..ff25b07e 100644
--- a/response/core/views.py
+++ b/response/core/views.py
@@ -2,6 +2,7 @@
 
 from response.core import serializers
 from response.core.models.action import Action
+from response.core.models.event import Event
 from response.core.models.incident import Incident
 from response.core.models.timeline import TimelineEvent
 from response.core.models.user_external import ExternalUser
@@ -77,3 +78,8 @@ def get_queryset(self):
     def perform_create(self, serializer):
         incident_pk = self.kwargs["incident_pk"]
         serializer.save(incident_id=incident_pk)
+
+
+class EventsViewSet(viewsets.ModelViewSet):
+    queryset = Event.objects.all()
+    serializer_class = serializers.EventSerializer
diff --git a/response/models.py b/response/models.py
index ab421198..61d9efc0 100644
--- a/response/models.py
+++ b/response/models.py
@@ -1,4 +1,11 @@
-from .core.models import Action, ExternalUser, Incident, TimelineEvent
+from .core.models import (
+    Action,
+    Event,
+    ExternalUser,
+    Incident,
+    TimelineEvent,
+)
+
 from .slack.models import (
     CommsChannel,
     HeadlinePost,
@@ -9,6 +16,7 @@
 
 __all__ = (
     "Action",
+    "Event",
     "Incident",
     "TimelineEvent",
     "ExternalUser",
diff --git a/response/serializers.py b/response/serializers.py
index 2b9ce2f3..a74bf7d1 100644
--- a/response/serializers.py
+++ b/response/serializers.py
@@ -1,15 +1,17 @@
 from .core.serializers import (
     ActionSerializer,
     CommsChannelSerializer,
+    EventSerializer,
     ExternalUserSerializer,
     IncidentSerializer,
     TimelineEventSerializer,
 )
 
 __all__ = (
-    "ExternalUserSerializer",
-    "TimelineEventSerializer",
     "ActionSerializer",
     "CommsChannelSerializer",
+    "EventSerializer",
+    "ExternalUserSerializer",
     "IncidentSerializer",
+    "TimelineEventSerializer",
 )

From 5e6eca7e5effba7862c38a903f76e0aaa52d2f53 Mon Sep 17 00:00:00 2001
From: Matt Cottingham <mattcottingham@monzo.com>
Date: Wed, 6 Nov 2019 14:07:29 +0000
Subject: [PATCH 2/7] Allow event signals to be configured

---
 response/core/signals.py | 67 ++++++++++++++++++++++++++--------------
 1 file changed, 43 insertions(+), 24 deletions(-)

diff --git a/response/core/signals.py b/response/core/signals.py
index e13565b8..2ef27ca4 100644
--- a/response/core/signals.py
+++ b/response/core/signals.py
@@ -1,42 +1,61 @@
 from datetime import datetime
 
+import logging
+logger = logging.getLogger(__name__)
+
+import os
+
 from response.core.models import Action, Event, Incident
 from response.core.serializers import ActionSerializer, IncidentSerializer
 
+from django.conf import settings
 from django.db.models.signals import post_save
 from django.dispatch import receiver
+from django.utils.module_loading import import_string
 
-import logging
-logger = logging.getLogger(__name__)
 
+class ActionEventHandler():
+
+    def handle(sender, instance: Action, **kwargs):
+        logger.info(f"Handling post_save for action: {instance}")
+
+        event = Event()
+        event.event_type = Event.ACTION_EVENT_TYPE
+
+        # Event payload should be a dict for serializing to JSON.
+        event.payload = ActionSerializer(instance).data
+        event.payload["incident_id"] = instance.incident.pk
+        if "details_ui" in event.payload: del event.payload["details_ui"]
+
+        event.timestamp = datetime.now(tz=None)
+        event.save()
 
-@receiver(post_save, sender=Action)
-def emit_action_event(sender, instance: Action, **kwargs):
-    logger.info(f"Handling post_save for action: {instance}")
 
-    event = Event()
-    event.event_type = Event.ACTION_EVENT_TYPE
+class IncidentEventHandler():
 
-    # Event payload should be a dict for serializing to JSON.
-    event.payload = ActionSerializer(instance).data
-    event.payload["incident_id"] = instance.incident.pk
-    # TODO: define a serializer that elides this field (otherwise
-    # it is returned in incident responses too)
-    if "details_ui" in event.payload: del event.payload["details_ui"]
+    def handle(sender, instance: Incident, **kwargs):
+        logger.info(f"Handling post_save for incident: {instance}")
 
-    event.timestamp = datetime.now(tz=None)
-    event.save()
+        event = Event()
+        event.event_type = Event.INCIDENT_EVENT_TYPE
 
+        # Event payload should be a dict for serializing to JSON.
+        event.payload = IncidentSerializer(instance).data
+        # Actions generate their own events, no need to duplicate them here.
+        if "action_items" in event.payload: del event.payload["action_items"]
 
-@receiver(post_save, sender=Incident)
-def emit_incident_event(sender, instance: Incident, **kwargs):
-    logger.info(f"Handling post_save for incident: {instance}")
+        event.timestamp = datetime.now(tz=None)
+        event.save()
 
-    event = Event()
-    event.event_type = Event.INCIDENT_EVENT_TYPE
 
-    # Event payload should be a dict for serializing to JSON.
-    event.payload = IncidentSerializer(instance).data
+if hasattr(settings, "ACTION_EVENT_HANDLER_CLASS"):
+    cls = import_string(settings.ACTION_EVENT_HANDLER_CLASS)
+    post_save.connect(cls.handle, sender=Action)
+else:
+    post_save.connect(ActionEventHandler.handle, sender=Action)
 
-    event.timestamp = datetime.now(tz=None)
-    event.save()
+if hasattr(settings, "INCIDENT_EVENT_HANDLER_CLASS"):
+    cls = import_string(settings.INCIDENT_EVENT_HANDLER_CLASS)
+    post_save.connect(cls.handle, sender=Incident)
+else:
+    post_save.connect(IncidentEventHandler.handle, sender=Incident)

From 32a9d88bc284fff144c0c38a3f9fe61ad04e3ee0 Mon Sep 17 00:00:00 2001
From: Matt Cottingham <mattcottingham@monzo.com>
Date: Fri, 8 Nov 2019 10:37:51 +0000
Subject: [PATCH 3/7] Add migration for events

---
 response/migrations/0014_event.py | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)
 create mode 100644 response/migrations/0014_event.py

diff --git a/response/migrations/0014_event.py b/response/migrations/0014_event.py
new file mode 100644
index 00000000..ea20f7ec
--- /dev/null
+++ b/response/migrations/0014_event.py
@@ -0,0 +1,22 @@
+# Generated by Django 2.2.3 on 2019-11-07 17:34
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('response', '0013_incident_private'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Event',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('timestamp', models.DateTimeField()),
+                ('event_type', models.CharField(max_length=50)),
+                ('payload', models.TextField()),
+            ],
+        ),
+    ]
\ No newline at end of file

From 1e88561b7300f32eacd81f2dccc5f341ae1de7f5 Mon Sep 17 00:00:00 2001
From: Matt Cottingham <mattcottingham@monzo.com>
Date: Thu, 7 Nov 2019 16:35:01 +0000
Subject: [PATCH 4/7] API tests

---
 response/core/models/event.py | 10 +++++++---
 tests/api/test_events.py      | 31 +++++++++++++++++++++++++++++++
 tests/factories/__init__.py   |  2 ++
 tests/factories/action.py     |  3 +++
 tests/factories/event.py      | 26 ++++++++++++++++++++++++++
 5 files changed, 69 insertions(+), 3 deletions(-)
 create mode 100644 tests/api/test_events.py
 create mode 100644 tests/factories/event.py

diff --git a/response/core/models/event.py b/response/core/models/event.py
index d84dfcd3..1d6aadb2 100644
--- a/response/core/models/event.py
+++ b/response/core/models/event.py
@@ -1,12 +1,16 @@
-from django.contrib.postgres.fields import JSONField
+import json
 
 from django.db import models
 
 
 class Event(models.Model):
-    ACTION_EVENT_TYPE= "action_event"
+    ACTION_EVENT_TYPE = "action_event"
     INCIDENT_EVENT_TYPE = "incident_event"
 
     timestamp = models.DateTimeField()
     event_type = models.CharField(max_length=50)
-    payload = JSONField()
+    payload = models.TextField()
+
+    def save(self, *args, **kwargs):
+        self.payload = json.dumps(self.payload)
+        super().save(*args, **kwargs)
diff --git a/tests/api/test_events.py b/tests/api/test_events.py
new file mode 100644
index 00000000..022b3f92
--- /dev/null
+++ b/tests/api/test_events.py
@@ -0,0 +1,31 @@
+import json
+
+from tests.factories.event import EventFactory
+
+from django.urls import reverse
+from rest_framework.test import force_authenticate
+
+from response.core.views import EventsViewSet
+
+
+def test_list_events(arf, api_user):
+    persisted_events = EventFactory.create_batch(10)
+
+    req = arf.get(reverse("event-list"))
+    force_authenticate(req, user=api_user)
+    response = EventsViewSet.as_view({"get": "list"})(req)
+
+    assert response.status_code == 200, "Got non-200 response from API"
+    content = json.loads(response.rendered_content)
+
+    assert "results" in content, "Response didn't have results key"
+    events = content["results"]
+    assert len(events) == len(
+        persisted_events,
+    ), "Didn't get expected number of events back"
+
+    for event in events:
+        assert event["timestamp"]
+        assert event["event_type"]
+        payload = json.loads(event["payload"])
+        assert payload["report"]
diff --git a/tests/factories/__init__.py b/tests/factories/__init__.py
index 69c3b8f4..2accd465 100644
--- a/tests/factories/__init__.py
+++ b/tests/factories/__init__.py
@@ -2,6 +2,7 @@
 from .incident import IncidentFactory
 from .timeline import TimelineEventFactory
 from .user import ExternalUserFactory, UserFactory
+from .event import EventFactory
 
 __all__ = (
     "IncidentFactory",
@@ -9,4 +10,5 @@
     "UserFactory",
     "ActionFactory",
     "ExternalUserFactory",
+    "EventFactory",
 )
diff --git a/tests/factories/action.py b/tests/factories/action.py
index bce399c3..f2773f17 100644
--- a/tests/factories/action.py
+++ b/tests/factories/action.py
@@ -1,11 +1,14 @@
 import factory
 from faker import Factory
 
+from django.db.models.signals import post_save
+
 from response.core.models import Action
 
 faker = Factory.create()
 
 
+@factory.django.mute_signals(post_save)
 class ActionFactory(factory.DjangoModelFactory):
     class Meta:
         model = Action
diff --git a/tests/factories/event.py b/tests/factories/event.py
new file mode 100644
index 00000000..b0e9453d
--- /dev/null
+++ b/tests/factories/event.py
@@ -0,0 +1,26 @@
+import factory
+import random
+
+from faker import Factory
+
+from response.core.models import Event
+
+faker = Factory.create()
+
+
+class EventFactory(factory.DjangoModelFactory):
+    class Meta:
+        model = Event
+
+    timestamp = factory.LazyFunction(
+        lambda: faker.date_time_between(start_date="-6m", end_date="now", tzinfo=None)
+    )
+    event_type = random.choice([Event.INCIDENT_EVENT_TYPE])
+
+    # Using an Incident/Event factory here fails with a mysterious error:
+    # https://github.com/pytest-dev/pytest-django/issues/713 (using @pytest.mark...
+    # didn't resolve it). For now, a static fixture suffices.
+    payload = {
+        "report": "we're out of milk",
+        "impact": "making tea is difficult",
+    }

From d5083d4546284280e2888570b00f088df4a5fa25 Mon Sep 17 00:00:00 2001
From: Matt Cottingham <mattcottingham@monzo.com>
Date: Fri, 8 Nov 2019 10:38:49 +0000
Subject: [PATCH 5/7] Autoformat

---
 response/core/models/__init__.py  |  2 +-
 response/core/serializers.py      |  1 -
 response/core/signals.py          | 26 ++++++++++++++------------
 response/migrations/0014_event.py | 26 ++++++++++++++++----------
 response/models.py                |  9 +--------
 tests/api/test_events.py          |  5 ++---
 tests/factories/__init__.py       |  2 +-
 tests/factories/action.py         |  3 +--
 tests/factories/event.py          |  7 ++-----
 9 files changed, 38 insertions(+), 43 deletions(-)

diff --git a/response/core/models/__init__.py b/response/core/models/__init__.py
index 91b49d1e..cf58fe47 100644
--- a/response/core/models/__init__.py
+++ b/response/core/models/__init__.py
@@ -1,7 +1,7 @@
 from .action import Action
+from .event import Event
 from .incident import Incident
 from .timeline import TimelineEvent, add_incident_update_event
-from .event import Event
 from .user_external import ExternalUser
 
 __all__ = (
diff --git a/response/core/serializers.py b/response/core/serializers.py
index f451f0f1..e360d036 100644
--- a/response/core/serializers.py
+++ b/response/core/serializers.py
@@ -134,7 +134,6 @@ def update(self, instance, validated_data):
 
 
 class EventSerializer(serializers.ModelSerializer):
-
     class Meta:
         model = Event
         fields = ("id", "timestamp", "event_type", "payload")
diff --git a/response/core/signals.py b/response/core/signals.py
index 2ef27ca4..fb61d611 100644
--- a/response/core/signals.py
+++ b/response/core/signals.py
@@ -1,21 +1,22 @@
-from datetime import datetime
-
 import logging
-logger = logging.getLogger(__name__)
-
 import os
-
-from response.core.models import Action, Event, Incident
-from response.core.serializers import ActionSerializer, IncidentSerializer
+from datetime import datetime
 
 from django.conf import settings
 from django.db.models.signals import post_save
 from django.dispatch import receiver
 from django.utils.module_loading import import_string
 
+from response.core.models import Action, Event, Incident
+from response.core.serializers import ActionSerializer, IncidentSerializer
+
+logger = logging.getLogger(__name__)
 
-class ActionEventHandler():
 
+
+
+
+class ActionEventHandler:
     def handle(sender, instance: Action, **kwargs):
         logger.info(f"Handling post_save for action: {instance}")
 
@@ -25,14 +26,14 @@ def handle(sender, instance: Action, **kwargs):
         # Event payload should be a dict for serializing to JSON.
         event.payload = ActionSerializer(instance).data
         event.payload["incident_id"] = instance.incident.pk
-        if "details_ui" in event.payload: del event.payload["details_ui"]
+        if "details_ui" in event.payload:
+            del event.payload["details_ui"]
 
         event.timestamp = datetime.now(tz=None)
         event.save()
 
 
-class IncidentEventHandler():
-
+class IncidentEventHandler:
     def handle(sender, instance: Incident, **kwargs):
         logger.info(f"Handling post_save for incident: {instance}")
 
@@ -42,7 +43,8 @@ def handle(sender, instance: Incident, **kwargs):
         # Event payload should be a dict for serializing to JSON.
         event.payload = IncidentSerializer(instance).data
         # Actions generate their own events, no need to duplicate them here.
-        if "action_items" in event.payload: del event.payload["action_items"]
+        if "action_items" in event.payload:
+            del event.payload["action_items"]
 
         event.timestamp = datetime.now(tz=None)
         event.save()
diff --git a/response/migrations/0014_event.py b/response/migrations/0014_event.py
index ea20f7ec..666a28c9 100644
--- a/response/migrations/0014_event.py
+++ b/response/migrations/0014_event.py
@@ -5,18 +5,24 @@
 
 class Migration(migrations.Migration):
 
-    dependencies = [
-        ('response', '0013_incident_private'),
-    ]
+    dependencies = [("response", "0013_incident_private")]
 
     operations = [
         migrations.CreateModel(
-            name='Event',
+            name="Event",
             fields=[
-                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('timestamp', models.DateTimeField()),
-                ('event_type', models.CharField(max_length=50)),
-                ('payload', models.TextField()),
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("timestamp", models.DateTimeField()),
+                ("event_type", models.CharField(max_length=50)),
+                ("payload", models.TextField()),
             ],
-        ),
-    ]
\ No newline at end of file
+        )
+    ]
diff --git a/response/models.py b/response/models.py
index 61d9efc0..2d5a1452 100644
--- a/response/models.py
+++ b/response/models.py
@@ -1,11 +1,4 @@
-from .core.models import (
-    Action,
-    Event,
-    ExternalUser,
-    Incident,
-    TimelineEvent,
-)
-
+from .core.models import Action, Event, ExternalUser, Incident, TimelineEvent
 from .slack.models import (
     CommsChannel,
     HeadlinePost,
diff --git a/tests/api/test_events.py b/tests/api/test_events.py
index 022b3f92..545a0b84 100644
--- a/tests/api/test_events.py
+++ b/tests/api/test_events.py
@@ -1,11 +1,10 @@
 import json
 
-from tests.factories.event import EventFactory
-
 from django.urls import reverse
 from rest_framework.test import force_authenticate
 
 from response.core.views import EventsViewSet
+from tests.factories.event import EventFactory
 
 
 def test_list_events(arf, api_user):
@@ -21,7 +20,7 @@ def test_list_events(arf, api_user):
     assert "results" in content, "Response didn't have results key"
     events = content["results"]
     assert len(events) == len(
-        persisted_events,
+        persisted_events
     ), "Didn't get expected number of events back"
 
     for event in events:
diff --git a/tests/factories/__init__.py b/tests/factories/__init__.py
index 2accd465..51ce8ce4 100644
--- a/tests/factories/__init__.py
+++ b/tests/factories/__init__.py
@@ -1,8 +1,8 @@
 from .action import ActionFactory
+from .event import EventFactory
 from .incident import IncidentFactory
 from .timeline import TimelineEventFactory
 from .user import ExternalUserFactory, UserFactory
-from .event import EventFactory
 
 __all__ = (
     "IncidentFactory",
diff --git a/tests/factories/action.py b/tests/factories/action.py
index f2773f17..917d877f 100644
--- a/tests/factories/action.py
+++ b/tests/factories/action.py
@@ -1,7 +1,6 @@
 import factory
-from faker import Factory
-
 from django.db.models.signals import post_save
+from faker import Factory
 
 from response.core.models import Action
 
diff --git a/tests/factories/event.py b/tests/factories/event.py
index b0e9453d..f6832459 100644
--- a/tests/factories/event.py
+++ b/tests/factories/event.py
@@ -1,6 +1,6 @@
-import factory
 import random
 
+import factory
 from faker import Factory
 
 from response.core.models import Event
@@ -20,7 +20,4 @@ class Meta:
     # Using an Incident/Event factory here fails with a mysterious error:
     # https://github.com/pytest-dev/pytest-django/issues/713 (using @pytest.mark...
     # didn't resolve it). For now, a static fixture suffices.
-    payload = {
-        "report": "we're out of milk",
-        "impact": "making tea is difficult",
-    }
+    payload = {"report": "we're out of milk", "impact": "making tea is difficult"}

From fe22e36f95586bde7464c16a2d233958b4e20218 Mon Sep 17 00:00:00 2001
From: Matt Cottingham <mattcottingham@monzo.com>
Date: Fri, 8 Nov 2019 10:50:21 +0000
Subject: [PATCH 6/7] Make the linter happy

---
 response/apps.py         | 2 +-
 response/core/signals.py | 5 -----
 2 files changed, 1 insertion(+), 6 deletions(-)

diff --git a/response/apps.py b/response/apps.py
index a82a4f2b..08e97999 100644
--- a/response/apps.py
+++ b/response/apps.py
@@ -16,7 +16,7 @@ def ready(self):
             dialog_handlers,
         )
 
-        from .core import signals
+        from .core import signals  # noqa: F401
 
         site_settings.RESPONSE_LOGIN_REQUIRED = getattr(
             site_settings, "RESPONSE_LOGIN_REQUIRED", True
diff --git a/response/core/signals.py b/response/core/signals.py
index fb61d611..35a4615a 100644
--- a/response/core/signals.py
+++ b/response/core/signals.py
@@ -1,10 +1,8 @@
 import logging
-import os
 from datetime import datetime
 
 from django.conf import settings
 from django.db.models.signals import post_save
-from django.dispatch import receiver
 from django.utils.module_loading import import_string
 
 from response.core.models import Action, Event, Incident
@@ -13,9 +11,6 @@
 logger = logging.getLogger(__name__)
 
 
-
-
-
 class ActionEventHandler:
     def handle(sender, instance: Action, **kwargs):
         logger.info(f"Handling post_save for action: {instance}")

From 9553106f5747a706431515a27c2c4761c6c0162c Mon Sep 17 00:00:00 2001
From: Matt Cottingham <mattcottingham@monzo.com>
Date: Fri, 8 Nov 2019 10:51:50 +0000
Subject: [PATCH 7/7] Avoid clobbering previous import

---
 response/apps.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/response/apps.py b/response/apps.py
index 08e97999..612f1325 100644
--- a/response/apps.py
+++ b/response/apps.py
@@ -16,7 +16,7 @@ def ready(self):
             dialog_handlers,
         )
 
-        from .core import signals  # noqa: F401
+        from .core import signals as core_signals  # noqa: F401
 
         site_settings.RESPONSE_LOGIN_REQUIRED = getattr(
             site_settings, "RESPONSE_LOGIN_REQUIRED", True