Add prometheus counters for content types other than events (#13175)

changelog.d/13175.misc

+Add prometheus counters for ephemeral events and to device messages pushed to app services. Contributed by Brad @ Beeper.

synapse/appservice/api.py

@@ -53,6 +53,18 @@ sent_events_counter = Counter(
     "synapse_appservice_api_sent_events", "Number of events sent to the AS", ["service"]
 )
 
+sent_ephemeral_counter = Counter(
+    "synapse_appservice_api_sent_ephemeral",
+    "Number of ephemeral events sent to the AS",
+    ["service"],
+)
+
+sent_todevice_counter = Counter(
+    "synapse_appservice_api_sent_todevice",
+    "Number of todevice messages sent to the AS",
+    ["service"],
+)
+
 HOUR_IN_MS = 60 * 60 * 1000
 
 
@@ -310,6 +322,8 @@ class ApplicationServiceApi(SimpleHttpClient):
                 )
             sent_transactions_counter.labels(service.id).inc()
             sent_events_counter.labels(service.id).inc(len(serialized_events))
+            sent_ephemeral_counter.labels(service.id).inc(len(ephemeral))
+            sent_todevice_counter.labels(service.id).inc(len(to_device_messages))
             return True
         except CodeMessageException as e:
             logger.warning(