When we don't recognize a message from Telegram, respond with 200 OK so Telegram doesn't keep retrying.

hc/front/tests/test_add_telegram.py

@@ -61,7 +61,7 @@ class AddTelegramTestCase(BaseTestCase):
             "message": {"chat": {"id": 123, "type": "group"}}
         }))
 
-        # bad message type
+        # bad chat type
         samples.append(json.dumps({
             "message": {
                 "chat": {"id": 123, "type": "invalid"},
@@ -73,4 +73,10 @@ class AddTelegramTestCase(BaseTestCase):
             r = self.client.post("/integrations/telegram/bot/", sample,
                                  content_type="application/json")
 
-            self.assertEqual(r.status_code, 400)
+            if sample == "":
+                # Bad JSON payload
+                self.assertEqual(r.status_code, 400)
+            else:
+                # JSON decodes but message structure not recognized
+                self.assertEqual(r.status_code, 200)
+

hc/front/views.py

@@ -838,7 +838,9 @@ def telegram_bot(request):
     except ValueError:
         return HttpResponseBadRequest()
     except jsonschema.ValidationError:
-        return HttpResponseBadRequest()
+        # We don't recognize the message format, but don't want Telegram
+        # retrying this over and over again, so respond with 200 OK
+        return HttpResponse()
 
     if "/start" not in doc["message"]["text"]:
         return HttpResponse()