Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/grpc/_observability.py: 54%
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« prev ^ index » next coverage.py v7.3.2, created at 2023-12-08 06:45 +0000
1# Copyright 2023 The gRPC authors.
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7# http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
15from __future__ import annotations
17import abc
18import contextlib
19import logging
20import threading
21from typing import Any, Generator, Generic, List, Optional, TypeVar
23from grpc._cython import cygrpc as _cygrpc
25_LOGGER = logging.getLogger(__name__)
27_channel = Any # _channel.py imports this module.
28ClientCallTracerCapsule = TypeVar("ClientCallTracerCapsule")
29ServerCallTracerFactoryCapsule = TypeVar("ServerCallTracerFactoryCapsule")
31_plugin_lock: threading.RLock = threading.RLock()
32_OBSERVABILITY_PLUGIN: Optional["ObservabilityPlugin"] = None
33_SERVICES_TO_EXCLUDE: List[bytes] = [
34 b"google.monitoring.v3.MetricService",
35 b"google.devtools.cloudtrace.v2.TraceService",
36]
39class ObservabilityPlugin(
40 Generic[ClientCallTracerCapsule, ServerCallTracerFactoryCapsule],
41 metaclass=abc.ABCMeta,
42):
43 """Abstract base class for observability plugin.
45 *This is a semi-private class that was intended for the exclusive use of
46 the gRPC team.*
48 The ClientCallTracerCapsule and ClientCallTracerCapsule created by this
49 plugin should be inject to gRPC core using observability_init at the
50 start of a program, before any channels/servers are built.
52 Any future methods added to this interface cannot have the
53 @abc.abstractmethod annotation.
55 Attributes:
56 _stats_enabled: A bool indicates whether tracing is enabled.
57 _tracing_enabled: A bool indicates whether stats(metrics) is enabled.
58 """
60 _tracing_enabled: bool = False
61 _stats_enabled: bool = False
63 @abc.abstractmethod
64 def create_client_call_tracer(
65 self, method_name: bytes
66 ) -> ClientCallTracerCapsule:
67 """Creates a ClientCallTracerCapsule.
69 After register the plugin, if tracing or stats is enabled, this method
70 will be called after a call was created, the ClientCallTracer created
71 by this method will be saved to call context.
73 The ClientCallTracer is an object which implements `grpc_core::ClientCallTracer`
74 interface and wrapped in a PyCapsule using `client_call_tracer` as name.
76 Args:
77 method_name: The method name of the call in byte format.
79 Returns:
80 A PyCapsule which stores a ClientCallTracer object.
81 """
82 raise NotImplementedError()
84 @abc.abstractmethod
85 def delete_client_call_tracer(
86 self, client_call_tracer: ClientCallTracerCapsule
87 ) -> None:
88 """Deletes the ClientCallTracer stored in ClientCallTracerCapsule.
90 After register the plugin, if tracing or stats is enabled, this method
91 will be called at the end of the call to destroy the ClientCallTracer.
93 The ClientCallTracer is an object which implements `grpc_core::ClientCallTracer`
94 interface and wrapped in a PyCapsule using `client_call_tracer` as name.
96 Args:
97 client_call_tracer: A PyCapsule which stores a ClientCallTracer object.
98 """
99 raise NotImplementedError()
101 @abc.abstractmethod
102 def save_trace_context(
103 self, trace_id: str, span_id: str, is_sampled: bool
104 ) -> None:
105 """Saves the trace_id and span_id related to the current span.
107 After register the plugin, if tracing is enabled, this method will be
108 called after the server finished sending response.
110 This method can be used to propagate census context.
112 Args:
113 trace_id: The identifier for the trace associated with the span as a
114 32-character hexadecimal encoded string,
115 e.g. 26ed0036f2eff2b7317bccce3e28d01f
116 span_id: The identifier for the span as a 16-character hexadecimal encoded
117 string. e.g. 113ec879e62583bc
118 is_sampled: A bool indicates whether the span is sampled.
119 """
120 raise NotImplementedError()
122 @abc.abstractmethod
123 def create_server_call_tracer_factory(
124 self,
125 ) -> ServerCallTracerFactoryCapsule:
126 """Creates a ServerCallTracerFactoryCapsule.
128 After register the plugin, if tracing or stats is enabled, this method
129 will be called by calling observability_init, the ServerCallTracerFactory
130 created by this method will be registered to gRPC core.
132 The ServerCallTracerFactory is an object which implements
133 `grpc_core::ServerCallTracerFactory` interface and wrapped in a PyCapsule
134 using `server_call_tracer_factory` as name.
136 Returns:
137 A PyCapsule which stores a ServerCallTracerFactory object.
138 """
139 raise NotImplementedError()
141 @abc.abstractmethod
142 def record_rpc_latency(
143 self, method: str, rpc_latency: float, status_code: Any
144 ) -> None:
145 """Record the latency of the RPC.
147 After register the plugin, if stats is enabled, this method will be
148 called at the end of each RPC.
150 Args:
151 method: The fully-qualified name of the RPC method being invoked.
152 rpc_latency: The latency for the RPC, equals to the time between
153 when the client invokes the RPC and when the client receives the status.
154 status_code: An element of grpc.StatusCode in string format representing the
155 final status for the RPC.
156 """
157 raise NotImplementedError()
159 def set_tracing(self, enable: bool) -> None:
160 """Enable or disable tracing.
162 Args:
163 enable: A bool indicates whether tracing should be enabled.
164 """
165 self._tracing_enabled = enable
167 def set_stats(self, enable: bool) -> None:
168 """Enable or disable stats(metrics).
170 Args:
171 enable: A bool indicates whether stats should be enabled.
172 """
173 self._stats_enabled = enable
175 @property
176 def tracing_enabled(self) -> bool:
177 return self._tracing_enabled
179 @property
180 def stats_enabled(self) -> bool:
181 return self._stats_enabled
183 @property
184 def observability_enabled(self) -> bool:
185 return self.tracing_enabled or self.stats_enabled
188@contextlib.contextmanager
189def get_plugin() -> Generator[Optional[ObservabilityPlugin], None, None]:
190 """Get the ObservabilityPlugin in _observability module.
192 Returns:
193 The ObservabilityPlugin currently registered with the _observability
194 module. Or None if no plugin exists at the time of calling this method.
195 """
196 with _plugin_lock:
197 yield _OBSERVABILITY_PLUGIN
200def set_plugin(observability_plugin: Optional[ObservabilityPlugin]) -> None:
201 """Save ObservabilityPlugin to _observability module.
203 Args:
204 observability_plugin: The ObservabilityPlugin to save.
206 Raises:
207 ValueError: If an ObservabilityPlugin was already registered at the
208 time of calling this method.
209 """
210 global _OBSERVABILITY_PLUGIN # pylint: disable=global-statement
211 with _plugin_lock:
212 if observability_plugin and _OBSERVABILITY_PLUGIN:
213 raise ValueError("observability_plugin was already set!")
214 _OBSERVABILITY_PLUGIN = observability_plugin
217def observability_init(observability_plugin: ObservabilityPlugin) -> None:
218 """Initialize observability with provided ObservabilityPlugin.
220 This method have to be called at the start of a program, before any
221 channels/servers are built.
223 Args:
224 observability_plugin: The ObservabilityPlugin to use.
226 Raises:
227 ValueError: If an ObservabilityPlugin was already registered at the
228 time of calling this method.
229 """
230 set_plugin(observability_plugin)
231 try:
232 _cygrpc.set_server_call_tracer_factory(observability_plugin)
233 except Exception: # pylint:disable=broad-except
234 _LOGGER.exception("Failed to set server call tracer factory!")
237def observability_deinit() -> None:
238 """Clear the observability context, including ObservabilityPlugin and
239 ServerCallTracerFactory
241 This method have to be called after exit observability context so that
242 it's possible to re-initialize again.
243 """
244 set_plugin(None)
245 _cygrpc.clear_server_call_tracer_factory()
248def delete_call_tracer(client_call_tracer_capsule: Any) -> None:
249 """Deletes the ClientCallTracer stored in ClientCallTracerCapsule.
251 This method will be called at the end of the call to destroy the ClientCallTracer.
253 The ClientCallTracer is an object which implements `grpc_core::ClientCallTracer`
254 interface and wrapped in a PyCapsule using `client_call_tracer` as the name.
256 Args:
257 client_call_tracer_capsule: A PyCapsule which stores a ClientCallTracer object.
258 """
259 with get_plugin() as plugin:
260 if not (plugin and plugin.observability_enabled):
261 return
262 plugin.delete_client_call_tracer(client_call_tracer_capsule)
265def maybe_record_rpc_latency(state: "_channel._RPCState") -> None:
266 """Record the latency of the RPC, if the plugin is registered and stats is enabled.
268 This method will be called at the end of each RPC.
270 Args:
271 state: a grpc._channel._RPCState object which contains the stats related to the
272 RPC.
273 """
274 # TODO(xuanwn): use channel args to exclude those metrics.
275 for exclude_prefix in _SERVICES_TO_EXCLUDE:
276 if exclude_prefix in state.method.encode("utf8"):
277 return
278 with get_plugin() as plugin:
279 if not (plugin and plugin.stats_enabled):
280 return
281 rpc_latency_s = state.rpc_end_time - state.rpc_start_time
282 rpc_latency_ms = rpc_latency_s * 1000
283 plugin.record_rpc_latency(state.method, rpc_latency_ms, state.code)