factor out uri redaction into a method on http

synapse/http/__init__.py

@@ -13,6 +13,8 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+import re
+
 from twisted.internet.defer import CancelledError
 from twisted.python import failure
 
@@ -34,3 +36,14 @@ def cancelled_to_request_timed_out_error(value, timeout):
         value.trap(CancelledError)
         raise RequestTimedOutError()
     return value
+
+
+ACCESS_TOKEN_RE = re.compile(br'(\?.*access(_|%5[Ff])token=)[^&]*(.*)$')
+
+
+def redact_uri(uri):
+    """Strips access tokens from the uri replaces with <redacted>"""
+    return ACCESS_TOKEN_RE.sub(
+        br'\1<redacted>\3',
+        uri
+    )

synapse/http/client.py

@@ -19,8 +19,7 @@ from OpenSSL.SSL import VERIFY_NONE
 from synapse.api.errors import (
     CodeMessageException, MatrixCodeMessageException, SynapseError, Codes,
 )
-from synapse.http import cancelled_to_request_timed_out_error
-from synapse.http.site import ACCESS_TOKEN_RE
+from synapse.http import cancelled_to_request_timed_out_error, redact_uri
 from synapse.util.async import add_timeout_to_deferred
 from synapse.util.caches import CACHE_SIZE_FACTOR
 from synapse.util.logcontext import make_deferred_yieldable
@@ -92,10 +91,7 @@ class SimpleHttpClient(object):
         outgoing_requests_counter.labels(method).inc()
 
         # log request but strip `access_token` (AS requests for example include this)
-        logger.info("Sending request %s %s", method, ACCESS_TOKEN_RE.sub(
-            r'\1<redacted>\3',
-            uri
-        ))
+        logger.info("Sending request %s %s", method, redact_uri(uri))
 
         try:
             request_deferred = self.agent.request(

synapse/http/site.py

@@ -14,18 +14,16 @@
 
 import contextlib
 import logging
-import re
 import time
 
 from twisted.web.server import Site, Request
 
+from synapse.http import redact_uri
 from synapse.http.request_metrics import RequestMetrics
 from synapse.util.logcontext import LoggingContext
 
 logger = logging.getLogger(__name__)
 
-ACCESS_TOKEN_RE = re.compile(br'(\?.*access(_|%5[Ff])token=)[^&]*(.*)$')
-
 _next_request_seq = 0
 
 
@@ -69,10 +67,7 @@ class SynapseRequest(Request):
         return "%s-%i" % (self.method, self.request_seq)
 
     def get_redacted_uri(self):
-        return ACCESS_TOKEN_RE.sub(
-            br'\1<redacted>\3',
-            self.uri
-        )
+        return redact_uri(self.uri)
 
     def get_user_agent(self):
         return self.requestHeaders.getRawHeaders(b"User-Agent", [None])[-1]