Make matrixfederationclient log more nicely

synapse/http/matrixfederationclient.py

@@ -16,6 +16,7 @@
 
 from twisted.internet import defer, reactor, protocol
 from twisted.internet.error import DNSLookupError
+from twisted.python.failure import Failure
 from twisted.web.client import readBody, _AgentBase, _URI
 from twisted.web.http_headers import Headers
 from twisted.web._newclient import ResponseDone
@@ -146,14 +147,22 @@ class MatrixFederationHttpClient(object):
                     )
                     raise SynapseError(400, "Domain specified not found.")
 
+                if hasattr(e, "reasons"):
+                    reasons = ", ".join(
+                        f.value.message
+                        for f in e.reasons
+                    )
+                else:
+                    reasons = e.message
+
                 logger.warn(
-                    "Sending request failed to %s: %s %s : %s",
+                    "Sending request failed to %s: %s %s: %s - %s",
                     destination,
                     method,
                     url_bytes,
-                    e
+                    type(e). __name__,
+                    reasons,
                 )
-                _print_ex(e)
 
                 if retries_left:
                     yield sleep(2 ** (5 - retries_left))
@@ -447,14 +456,6 @@ def _readBodyToFile(response, stream, max_size):
     return d
 
 
-def _print_ex(e):
-    if hasattr(e, "reasons") and e.reasons:
-        for ex in e.reasons:
-            _print_ex(ex)
-    else:
-        logger.warn(e)
-
-
 class _JsonProducer(object):
     """ Used by the twisted http client to create the HTTP body from json
     """