Merge pull request #780 from readthedocs/davidfischer/notify-ad-image…

…-changes

Slack alert when ad images change

adserver/forms.py

@@ -35,6 +35,7 @@
 from .models import Publisher
 from .models import Region
 from .models import Topic
+from .tasks import notify_on_ad_image_change
 from .validators import TargetingParametersValidator
 
 
@@ -953,7 +954,17 @@ def save(self, commit=True):
         if not self.instance.slug:
             # Only needed on create
             self.instance.slug = self.generate_slug()
-        return super().save(commit)
+
+        new_instance = super().save(commit)
+
+        # Check if the image has changed
+        # We alert on this as a secondary check for malicious images
+        # https://docs.djangoproject.com/en/3.2/ref/forms/api/#django.forms.Form.changed_data
+        if new_instance.image and "image" in self.changed_data:
+            log.debug("Image field has changed: %s", new_instance.image.url)
+            notify_on_ad_image_change.apply_async(args=[new_instance.pk])
+
+        return new_instance
 
     class Meta:
         model = Advertisement

adserver/tasks.py

@@ -731,6 +731,23 @@ def calculate_ad_ctrs(days=7, min_views=1_000):
             ad.save()
 
 
+@app.task()
+def notify_on_ad_image_change(advertisement_id):
+    ad = Advertisement.objects.filter(id=advertisement_id).first()
+    if not ad or not ad.image:
+        log.warning("Invalid ad passed to 'notify_on_ad_image_change'")
+        return
+
+    ad_url = generate_absolute_url(ad.get_absolute_url())
+    message = f"Ad <{ad_url}|{ad.name}> had its image changed to {ad.image.url}"
+
+    log.info(message)
+    slack_message(
+        "adserver/slack/generic-message.slack",
+        {"text": message},
+    )
+
+
 @app.task()
 def notify_of_completed_flights():
     """Send a note and close flights which completed in the last day."""