diff options
Diffstat (limited to 'synapse/logging/opentracing.py')
| -rw-r--r-- | synapse/logging/opentracing.py | 114 |
1 files changed, 80 insertions, 34 deletions
diff --git a/synapse/logging/opentracing.py b/synapse/logging/opentracing.py index 256b972aaa..7246253018 100644 --- a/synapse/logging/opentracing.py +++ b/synapse/logging/opentracing.py @@ -239,8 +239,7 @@ _homeserver_whitelist = None def only_if_tracing(func): - """Executes the function only if we're tracing. Otherwise return. - Assumes the function wrapped may return None""" + """Executes the function only if we're tracing. Otherwise returns None.""" @wraps(func) def _only_if_tracing_inner(*args, **kwargs): @@ -252,6 +251,41 @@ def only_if_tracing(func): return _only_if_tracing_inner +def ensure_active_span(message, ret=None): + """Executes the operation only if opentracing is enabled and there is an active span. + If there is no active span it logs message at the error level. + + Args: + message (str): Message which fills in "There was no active span when trying to %s" + in the error log if there is no active span and opentracing is enabled. + ret (object): return value if opentracing is None or there is no active span. + + Returns (object): The result of the func or ret if opentracing is disabled or there + was no active span. + """ + + def ensure_active_span_inner_1(func): + @wraps(func) + def ensure_active_span_inner_2(*args, **kwargs): + if not opentracing: + return ret + + if not opentracing.tracer.active_span: + logger.error( + "There was no active span when trying to %s." + " Did you forget to start one or did a context slip?", + message, + ) + + return ret + + return func(*args, **kwargs) + + return ensure_active_span_inner_2 + + return ensure_active_span_inner_1 + + @contextlib.contextmanager def _noop_context_manager(*args, **kwargs): """Does exactly what it says on the tin""" @@ -319,7 +353,7 @@ def whitelisted_homeserver(destination): Args: destination (str) """ - _homeserver_whitelist + if _homeserver_whitelist: return _homeserver_whitelist.match(destination) return False @@ -349,26 +383,24 @@ def start_active_span( if opentracing is None: return _noop_context_manager() - else: - # We need to enter the scope here for the logcontext to become active - return opentracing.tracer.start_active_span( - operation_name, - child_of=child_of, - references=references, - tags=tags, - start_time=start_time, - ignore_active_span=ignore_active_span, - finish_on_close=finish_on_close, - ) + return opentracing.tracer.start_active_span( + operation_name, + child_of=child_of, + references=references, + tags=tags, + start_time=start_time, + ignore_active_span=ignore_active_span, + finish_on_close=finish_on_close, + ) def start_active_span_follows_from(operation_name, contexts): if opentracing is None: return _noop_context_manager() - else: - references = [opentracing.follows_from(context) for context in contexts] - scope = start_active_span(operation_name, references=references) - return scope + + references = [opentracing.follows_from(context) for context in contexts] + scope = start_active_span(operation_name, references=references) + return scope def start_active_span_from_request( @@ -465,19 +497,19 @@ def start_active_span_from_edu( # Opentracing setters for tags, logs, etc -@only_if_tracing +@ensure_active_span("set a tag") def set_tag(key, value): """Sets a tag on the active span""" opentracing.tracer.active_span.set_tag(key, value) -@only_if_tracing +@ensure_active_span("log") def log_kv(key_values, timestamp=None): """Log to the active span""" opentracing.tracer.active_span.log_kv(key_values, timestamp) -@only_if_tracing +@ensure_active_span("set the traces operation name") def set_operation_name(operation_name): """Sets the operation name of the active span""" opentracing.tracer.active_span.set_operation_name(operation_name) @@ -486,13 +518,18 @@ def set_operation_name(operation_name): # Injection and extraction -@only_if_tracing +@ensure_active_span("inject the span into a header") def inject_active_span_twisted_headers(headers, destination, check_destination=True): """ Injects a span context into twisted headers in-place Args: headers (twisted.web.http_headers.Headers) + destination (str): address of entity receiving the span context. If check_destination + is true the context will only be injected if the destination matches the + opentracing whitelist + check_destination (bool): If false, destination will be ignored and the context + will always be injected. span (opentracing.Span) Returns: @@ -517,7 +554,7 @@ def inject_active_span_twisted_headers(headers, destination, check_destination=T headers.addRawHeaders(key, value) -@only_if_tracing +@ensure_active_span("inject the span into a byte dict") def inject_active_span_byte_dict(headers, destination, check_destination=True): """ Injects a span context into a dict where the headers are encoded as byte @@ -525,6 +562,11 @@ def inject_active_span_byte_dict(headers, destination, check_destination=True): Args: headers (dict) + destination (str): address of entity receiving the span context. If check_destination + is true the context will only be injected if the destination matches the + opentracing whitelist + check_destination (bool): If false, destination will be ignored and the context + will always be injected. span (opentracing.Span) Returns: @@ -537,7 +579,7 @@ def inject_active_span_byte_dict(headers, destination, check_destination=True): here: https://github.com/jaegertracing/jaeger-client-python/blob/master/jaeger_client/constants.py """ - if not whitelisted_homeserver(destination): + if check_destination and not whitelisted_homeserver(destination): return span = opentracing.tracer.active_span @@ -549,16 +591,18 @@ def inject_active_span_byte_dict(headers, destination, check_destination=True): headers[key.encode()] = [value.encode()] -@only_if_tracing +@ensure_active_span("inject the span into a text map") def inject_active_span_text_map(carrier, destination, check_destination=True): """ Injects a span context into a dict Args: carrier (dict) - destination (str): the name of the remote server. The span context - will only be injected if the destination matches the homeserver_whitelist - or destination is None. + destination (str): address of entity receiving the span context. If check_destination + is true the context will only be injected if the destination matches the + opentracing whitelist + check_destination (bool): If false, destination will be ignored and the context + will always be injected. Returns: In-place modification of carrier @@ -579,6 +623,7 @@ def inject_active_span_text_map(carrier, destination, check_destination=True): ) +@ensure_active_span("get the active span context as a dict", ret={}) def get_active_span_text_map(destination=None): """ Gets a span context as a dict. This can be used instead of manually @@ -591,7 +636,7 @@ def get_active_span_text_map(destination=None): dict: the active span's context if opentracing is enabled, otherwise empty. """ - if not opentracing or (destination and not whitelisted_homeserver(destination)): + if destination and not whitelisted_homeserver(destination): return {} carrier = {} @@ -602,6 +647,7 @@ def get_active_span_text_map(destination=None): return carrier +@ensure_active_span("get the span context as a string.", ret={}) def active_span_context_as_string(): """ Returns: @@ -656,15 +702,15 @@ def trace(func=None, opname=None): _opname = opname if opname else func.__name__ @wraps(func) - def _trace_inner(self, *args, **kwargs): + def _trace_inner(*args, **kwargs): if opentracing is None: - return func(self, *args, **kwargs) + return func(*args, **kwargs) scope = start_active_span(_opname) scope.__enter__() try: - result = func(self, *args, **kwargs) + result = func(*args, **kwargs) if isinstance(result, defer.Deferred): def call_back(result): @@ -704,13 +750,13 @@ def tag_args(func): return func @wraps(func) - def _tag_args_inner(self, *args, **kwargs): + def _tag_args_inner(*args, **kwargs): argspec = inspect.getargspec(func) for i, arg in enumerate(argspec.args[1:]): set_tag("ARG_" + arg, args[i]) set_tag("args", args[len(argspec.args) :]) set_tag("kwargs", kwargs) - return func(self, *args, **kwargs) + return func(*args, **kwargs) return _tag_args_inner |