From f7c873a64355506221648d55d64023c83d43f618 Mon Sep 17 00:00:00 2001
From: Jorik Schellekens <joriksch@gmail.com>
Date: Thu, 5 Sep 2019 17:44:55 +0100
Subject: [PATCH] Trace how long it takes for the send trasaction to complete,
 including retrys (#5986)

---
 changelog.d/5986.feature               |  1 +
 synapse/http/client.py                 | 83 +++++++++++++++-----------
 synapse/http/matrixfederationclient.py |  1 -
 synapse/replication/http/_base.py      |  7 ++-
 4 files changed, 56 insertions(+), 36 deletions(-)
 create mode 100644 changelog.d/5986.feature

diff --git a/changelog.d/5986.feature b/changelog.d/5986.feature
new file mode 100644
index 000000000..f56aec1b3
--- /dev/null
+++ b/changelog.d/5986.feature
@@ -0,0 +1 @@
+Trace replication send times.
diff --git a/synapse/http/client.py b/synapse/http/client.py
index 0ae6db8ea..51765ae3c 100644
--- a/synapse/http/client.py
+++ b/synapse/http/client.py
@@ -46,6 +46,7 @@ from synapse.http import (
     redact_uri,
 )
 from synapse.logging.context import make_deferred_yieldable
+from synapse.logging.opentracing import set_tag, start_active_span, tags
 from synapse.util.async_helpers import timeout_deferred
 from synapse.util.caches import CACHE_SIZE_FACTOR
 
@@ -269,42 +270,56 @@ class SimpleHttpClient(object):
         # log request but strip `access_token` (AS requests for example include this)
         logger.info("Sending request %s %s", method, redact_uri(uri))
 
-        try:
-            body_producer = None
-            if data is not None:
-                body_producer = QuieterFileBodyProducer(BytesIO(data))
+        with start_active_span(
+            "outgoing-client-request",
+            tags={
+                tags.SPAN_KIND: tags.SPAN_KIND_RPC_CLIENT,
+                tags.HTTP_METHOD: method,
+                tags.HTTP_URL: uri,
+            },
+            finish_on_close=True,
+        ):
+            try:
+                body_producer = None
+                if data is not None:
+                    body_producer = QuieterFileBodyProducer(BytesIO(data))
 
-            request_deferred = treq.request(
-                method,
-                uri,
-                agent=self.agent,
-                data=body_producer,
-                headers=headers,
-                **self._extra_treq_args
-            )
-            request_deferred = timeout_deferred(
-                request_deferred,
-                60,
-                self.hs.get_reactor(),
-                cancelled_to_request_timed_out_error,
-            )
-            response = yield make_deferred_yieldable(request_deferred)
+                request_deferred = treq.request(
+                    method,
+                    uri,
+                    agent=self.agent,
+                    data=body_producer,
+                    headers=headers,
+                    **self._extra_treq_args
+                )
+                request_deferred = timeout_deferred(
+                    request_deferred,
+                    60,
+                    self.hs.get_reactor(),
+                    cancelled_to_request_timed_out_error,
+                )
+                response = yield make_deferred_yieldable(request_deferred)
 
-            incoming_responses_counter.labels(method, response.code).inc()
-            logger.info(
-                "Received response to %s %s: %s", method, redact_uri(uri), response.code
-            )
-            return response
-        except Exception as e:
-            incoming_responses_counter.labels(method, "ERR").inc()
-            logger.info(
-                "Error sending request to  %s %s: %s %s",
-                method,
-                redact_uri(uri),
-                type(e).__name__,
-                e.args[0],
-            )
-            raise
+                incoming_responses_counter.labels(method, response.code).inc()
+                logger.info(
+                    "Received response to %s %s: %s",
+                    method,
+                    redact_uri(uri),
+                    response.code,
+                )
+                return response
+            except Exception as e:
+                incoming_responses_counter.labels(method, "ERR").inc()
+                logger.info(
+                    "Error sending request to  %s %s: %s %s",
+                    method,
+                    redact_uri(uri),
+                    type(e).__name__,
+                    e.args[0],
+                )
+                set_tag(tags.ERROR, True)
+                set_tag("error_reason", e.args[0])
+                raise
 
     @defer.inlineCallbacks
     def post_urlencoded_get_json(self, uri, args={}, headers=None):
diff --git a/synapse/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py
index 4326e98a2..3f7c93ffc 100644
--- a/synapse/http/matrixfederationclient.py
+++ b/synapse/http/matrixfederationclient.py
@@ -345,7 +345,6 @@ class MatrixFederationHttpClient(object):
         else:
             query_bytes = b""
 
-        # Retreive current span
         scope = start_active_span(
             "outgoing-federation-request",
             tags={
diff --git a/synapse/replication/http/_base.py b/synapse/replication/http/_base.py
index afc9a8ff2..03560c1f0 100644
--- a/synapse/replication/http/_base.py
+++ b/synapse/replication/http/_base.py
@@ -28,7 +28,11 @@ from synapse.api.errors import (
     RequestSendFailed,
     SynapseError,
 )
-from synapse.logging.opentracing import inject_active_span_byte_dict, trace_servlet
+from synapse.logging.opentracing import (
+    inject_active_span_byte_dict,
+    trace,
+    trace_servlet,
+)
 from synapse.util.caches.response_cache import ResponseCache
 from synapse.util.stringutils import random_string
 
@@ -129,6 +133,7 @@ class ReplicationEndpoint(object):
 
         client = hs.get_simple_http_client()
 
+        @trace(opname="outgoing_replication_request")
         @defer.inlineCallbacks
         def send_request(**kwargs):
             data = yield cls._serialize_payload(**kwargs)