Merge pull request #13 from matrix-org/request_logging

Request logging

10 files changed, 247 insertions, 51 deletions

diff --git a/synapse/app/homeserver.py b/synapse/app/homeserver.py
index 43164c8d67..85284a4919 100755
--- a/synapse/app/homeserver.py
+++ b/synapse/app/homeserver.py
@@ -33,6 +33,7 @@ from synapse.api.urls import (
 )
 from synapse.config.homeserver import HomeServerConfig
 from synapse.crypto import context_factory
+from synapse.util.logcontext import LoggingContext
 
 from daemonize import Daemonize
 import twisted.manhole.telnet
@@ -246,7 +247,7 @@ def setup():
         daemon = Daemonize(
             app="synapse-homeserver",
             pid=config.pid_file,
-            action=reactor.run,
+            action=run,
             auto_close_fds=False,
             verbose=True,
             logger=logger,
@@ -256,6 +257,13 @@ def setup():
     else:
         reactor.run()
 
+def run():
+    with LoggingContext("run"):
+        reactor.run()
+
+def main():
+    with LoggingContext("main"):
+        setup()
 
 if __name__ == '__main__':
-    setup()
+    main()
diff --git a/synapse/config/logger.py b/synapse/config/logger.py
index 05611d02f7..8566296433 100644
--- a/synapse/config/logger.py
+++ b/synapse/config/logger.py
@@ -14,7 +14,7 @@
 # limitations under the License.
 
 from ._base import Config
-
+from synapse.util.logcontext import LoggingContextFilter
 from twisted.python.log import PythonLoggingObserver
 import logging
 import logging.config
@@ -46,7 +46,8 @@ class LoggingConfig(Config):
 
     def setup_logging(self):
         log_format = (
-            '%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(message)s'
+            "%(asctime)s - %(name)s - %(lineno)d - %(levelname)s - %(request)s"
+            " - %(message)s"
         )
         if self.log_config is None:
 
@@ -54,13 +55,20 @@ class LoggingConfig(Config):
             if self.verbosity:
                 level = logging.DEBUG
 
-               # FIXME: we need a logging.WARN for a -q quiet option
+            # FIXME: we need a logging.WARN for a -q quiet option
+            logger = logging.getLogger('')
+            logger.setLevel(level)
+            formatter = logging.Formatter(log_format)
+            if self.log_file:
+                handler = logging.FileHandler(self.log_file)
+            else:
+                handler = logging.StreamHandler()
+            handler.setFormatter(formatter)
+
+            handler.addFilter(LoggingContextFilter(request=""))
 
-            logging.basicConfig(
-                level=level,
-                filename=self.log_file,
-                format=log_format
-            )
+            logger.addHandler(handler)
+            logger.info("Test")
         else:
             logging.config.fileConfig(self.log_config)
 
diff --git a/synapse/crypto/keyclient.py b/synapse/crypto/keyclient.py
index 5191be4570..bb1f400b54 100644
--- a/synapse/crypto/keyclient.py
+++ b/synapse/crypto/keyclient.py
@@ -18,6 +18,7 @@ from twisted.web.http import HTTPClient
 from twisted.internet.protocol import Factory
 from twisted.internet import defer, reactor
 from synapse.http.endpoint import matrix_endpoint
+from synapse.util.logcontext import PreserveLoggingContext
 import json
 import logging
 
@@ -36,10 +37,11 @@ def fetch_server_key(server_name, ssl_context_factory):
 
     for i in range(5):
         try:
-            protocol = yield endpoint.connect(factory)
-            server_response, server_certificate = yield protocol.remote_key
-            defer.returnValue((server_response, server_certificate))
-            return
+            with PreserveLoggingContext():
+                protocol = yield endpoint.connect(factory)
+                server_response, server_certificate = yield protocol.remote_key
+                defer.returnValue((server_response, server_certificate))
+                return
         except Exception as e:
             logger.exception(e)
     raise IOError("Cannot get key for %s" % server_name)
diff --git a/synapse/http/client.py b/synapse/http/client.py
index c34b086eb9..29e6053bc1 100644
--- a/synapse/http/client.py
+++ b/synapse/http/client.py
@@ -23,6 +23,7 @@ from twisted.web.http_headers import Headers
 
 from synapse.http.endpoint import matrix_endpoint
 from synapse.util.async import sleep
+from synapse.util.logcontext import PreserveLoggingContext
 
 from syutil.jsonutil import encode_canonical_json
 
@@ -108,16 +109,17 @@ class BaseHttpClient(object):
                 producer = body_callback(method, url_bytes, headers_dict)
 
             try:
-                response = yield self.agent.request(
-                    destination,
-                    endpoint,
-                    method,
-                    path_bytes,
-                    param_bytes,
-                    query_bytes,
-                    Headers(headers_dict),
-                    producer
-                )
+                with PreserveLoggingContext():
+                    response = yield self.agent.request(
+                        destination,
+                        endpoint,
+                        method,
+                        path_bytes,
+                        param_bytes,
+                        query_bytes,
+                        Headers(headers_dict),
+                        producer
+                    )
 
                 logger.debug("Got response to %s", method)
                 break
diff --git a/synapse/http/server.py b/synapse/http/server.py
index 8d419c02dd..ed1f1170cb 100644
--- a/synapse/http/server.py
+++ b/synapse/http/server.py
@@ -20,6 +20,7 @@ from syutil.jsonutil import (
 from synapse.api.errors import (
     cs_exception, SynapseError, CodeMessageException
 )
+from synapse.util.logcontext import LoggingContext
 
 from twisted.internet import defer, reactor
 from twisted.web import server, resource
@@ -88,9 +89,19 @@ class JsonResource(HttpServer, resource.Resource):
     def render(self, request):
         """ This get's called by twisted every time someone sends us a request.
         """
-        self._async_render(request)
+        self._async_render_with_logging_context(request)
         return server.NOT_DONE_YET
 
+    _request_id = 0
+
+    @defer.inlineCallbacks
+    def _async_render_with_logging_context(self, request):
+        request_id = "%s-%s" % (request.method, JsonResource._request_id)
+        JsonResource._request_id += 1
+        with LoggingContext(request_id) as request_context:
+            request_context.request = request_id
+            yield self._async_render(request)
+
     @defer.inlineCallbacks
     def _async_render(self, request):
         """ This get's called by twisted every time someone sends us a request.
diff --git a/synapse/storage/_base.py b/synapse/storage/_base.py
index 670387b04a..30e6eac8db 100644
--- a/synapse/storage/_base.py
+++ b/synapse/storage/_base.py
@@ -17,8 +17,11 @@ import logging
 from synapse.api.errors import StoreError
 from synapse.api.events.utils import prune_event
 from synapse.util.logutils import log_function
+from synapse.util.logcontext import PreserveLoggingContext, LoggingContext
 from syutil.base64util import encode_base64
 
+from twisted.internet import defer
+
 import collections
 import copy
 import json
@@ -84,32 +87,40 @@ class SQLBaseStore(object):
         self.event_factory = hs.get_event_factory()
         self._clock = hs.get_clock()
 
+    @defer.inlineCallbacks
     def runInteraction(self, desc, func, *args, **kwargs):
         """Wraps the .runInteraction() method on the underlying db_pool."""
+        current_context = LoggingContext.current_context()
         def inner_func(txn, *args, **kwargs):
-            start = time.clock() * 1000
-            txn_id = SQLBaseStore._TXN_ID
-
-            # We don't really need these to be unique, so lets stop it from
-            # growing really large.
-            self._TXN_ID = (self._TXN_ID + 1) % (sys.maxint - 1)
-
-            name = "%s-%x" % (desc, txn_id, )
-
-            transaction_logger.debug("[TXN START] {%s}", name)
-            try:
-                return func(LoggingTransaction(txn, name), *args, **kwargs)
-            except:
-                logger.exception("[TXN FAIL] {%s}", name)
-                raise
-            finally:
-                end = time.clock() * 1000
-                transaction_logger.debug(
-                    "[TXN END] {%s} %f",
-                    name, end - start
-                )
+            with LoggingContext("runInteraction") as context:
+                current_context.copy_to(context)
+                start = time.clock() * 1000
+                txn_id = SQLBaseStore._TXN_ID
+
+                # We don't really need these to be unique, so lets stop it from
+                # growing really large.
+                self._TXN_ID = (self._TXN_ID + 1) % (sys.maxint - 1)
+
+                name = "%s-%x" % (desc, txn_id, )
+
+                transaction_logger.debug("[TXN START] {%s}", name)
+                try:
+                    return func(LoggingTransaction(txn, name), *args, **kwargs)
+                except:
+                    logger.exception("[TXN FAIL] {%s}", name)
+                    raise
+                finally:
+                    end = time.clock() * 1000
+                    transaction_logger.debug(
+                        "[TXN END] {%s} %f",
+                        name, end - start
+                    )
 
-        return self._db_pool.runInteraction(inner_func, *args, **kwargs)
+        with PreserveLoggingContext():
+            result = yield self._db_pool.runInteraction(
+                inner_func, *args, **kwargs
+            )
+        defer.returnValue(result)
 
     def cursor_to_dict(self, cursor):
         """Converts a SQL cursor into an list of dicts.
@@ -177,7 +188,7 @@ class SQLBaseStore(object):
         )
 
         logger.debug(
-            "[SQL] %s  Args=%s Func=%s",
+            "[SQL] %s Args=%s",
             sql, values.values(),
         )
 
diff --git a/synapse/util/async.py b/synapse/util/async.py
index bf578f8bfb..1219d927db 100644
--- a/synapse/util/async.py
+++ b/synapse/util/async.py
@@ -16,15 +16,17 @@
 
 from twisted.internet import defer, reactor
 
+from .logcontext import PreserveLoggingContext
 
+@defer.inlineCallbacks
 def sleep(seconds):
     d = defer.Deferred()
     reactor.callLater(seconds, d.callback, seconds)
-    return d
-
+    with PreserveLoggingContext():
+        yield d
 
 def run_on_reactor():
     """ This will cause the rest of the function to be invoked upon the next
     iteration of the main loop
     """
-    return sleep(0)
\ No newline at end of file
+    return sleep(0)
diff --git a/synapse/util/logcontext.py b/synapse/util/logcontext.py
new file mode 100644
index 0000000000..13176b05ce
--- /dev/null
+++ b/synapse/util/logcontext.py
@@ -0,0 +1,108 @@
+import threading
+import logging
+
+
+class LoggingContext(object):
+    """Additional context for log formatting. Contexts are scoped within a
+    "with" block. Contexts inherit the state of their parent contexts.
+    Args:
+        name (str): Name for the context for debugging.
+    """
+
+    __slots__ = ["parent_context", "name", "__dict__"]
+
+    thread_local = threading.local()
+
+    class Sentinel(object):
+        """Sentinel to represent the root context"""
+
+        __slots__ = []
+
+        def copy_to(self, record):
+            pass
+
+    sentinel = Sentinel()
+
+    def __init__(self, name=None):
+        self.parent_context = None
+        self.name = name
+
+    def __str__(self):
+        return "%s@%x" % (self.name, id(self))
+
+    @classmethod
+    def current_context(cls):
+        """Get the current logging context from thread local storage"""
+        return getattr(cls.thread_local, "current_context", cls.sentinel)
+
+    def __enter__(self):
+        """Enters this logging context into thread local storage"""
+        if self.parent_context is not None:
+            raise Exception("Attempt to enter logging context multiple times")
+        self.parent_context = self.current_context()
+        self.thread_local.current_context = self
+        return self
+
+    def __exit__(self, type, value, traceback):
+        """Restore the logging context in thread local storage to the state it
+        was before this context was entered.
+        Returns:
+            None to avoid suppressing any exeptions that were thrown.
+        """
+        if self.thread_local.current_context is not self:
+            logging.error(
+                "Current logging context %s is not the expected context %s",
+                self.thread_local.current_context,
+                self
+            )
+        self.thread_local.current_context = self.parent_context
+        self.parent_context = None
+
+    def __getattr__(self, name):
+        """Delegate member lookup to parent context"""
+        return getattr(self.parent_context, name)
+
+    def copy_to(self, record):
+        """Copy fields from this context and its parents to the record"""
+        if self.parent_context is not None:
+            self.parent_context.copy_to(record)
+        for key, value in self.__dict__.items():
+            setattr(record, key, value)
+
+
+class LoggingContextFilter(logging.Filter):
+    """Logging filter that adds values from the current logging context to each
+    record.
+    Args:
+        **defaults: Default values to avoid formatters complaining about
+            missing fields
+    """
+    def __init__(self, **defaults):
+        self.defaults = defaults
+
+    def filter(self, record):
+        """Add each fields from the logging contexts to the record.
+        Returns:
+            True to include the record in the log output.
+        """
+        context = LoggingContext.current_context()
+        for key, value in self.defaults.items():
+            setattr(record, key, value)
+        context.copy_to(record)
+        return True
+
+
+class PreserveLoggingContext(object):
+    """Captures the current logging context and restores it when the scope is
+    exited. Used to restore the context after a function using
+    @defer.inlineCallbacks is resumed by a callback from the reactor."""
+
+    __slots__ = ["current_context"]
+
+    def __enter__(self):
+        """Captures the current logging context"""
+        self.current_context = LoggingContext.current_context()
+
+    def __exit__(self, type, value, traceback):
+        """Restores the current logging context"""
+        LoggingContext.thread_local.current_context = self.current_context
diff --git a/synapse/util/logutils.py b/synapse/util/logutils.py
index fadf0bd510..903a6cf1b3 100644
--- a/synapse/util/logutils.py
+++ b/synapse/util/logutils.py
@@ -75,6 +75,7 @@ def trace_function(f):
     linenum = f.func_code.co_firstlineno
     pathname = f.func_code.co_filename
 
+    @wraps(f)
     def wrapped(*args, **kwargs):
         name = f.__module__
         logger = logging.getLogger(name)
diff --git a/tests/util/test_log_context.py b/tests/util/test_log_context.py
new file mode 100644
index 0000000000..efa0f28bad
--- /dev/null
+++ b/tests/util/test_log_context.py
@@ -0,0 +1,43 @@
+from twisted.internet import defer
+from twisted.internet import reactor
+from .. import unittest
+
+from synapse.util.async import sleep
+from synapse.util.logcontext import LoggingContext
+
+class LoggingContextTestCase(unittest.TestCase):
+
+    def _check_test_key(self, value):
+        self.assertEquals(
+            LoggingContext.current_context().test_key, value
+        )
+
+    def test_with_context(self):
+        with LoggingContext() as context_one:
+            context_one.test_key = "test"
+            self._check_test_key("test")
+
+    def test_chaining(self):
+        with LoggingContext() as context_one:
+            context_one.test_key = "one"
+            with LoggingContext() as context_two:
+                self._check_test_key("one")
+                context_two.test_key = "two"
+                self._check_test_key("two")
+            self._check_test_key("one")
+
+    @defer.inlineCallbacks
+    def test_sleep(self):
+        @defer.inlineCallbacks
+        def competing_callback():
+            with LoggingContext() as competing_context:
+                competing_context.test_key = "competing"
+                yield sleep(0)
+                self._check_test_key("competing")
+
+        reactor.callLater(0, competing_callback)
+
+        with LoggingContext() as context_one:
+            context_one.test_key = "one"
+            yield sleep(0)
+            self._check_test_key("one")