Copy grpc_opentracing

Author: c24t

ext/opentelemetry-ext-grpc/src/opentelemetry/ext/grpc/__init__.py

@@ -1,13 +1,96 @@
-# Copyright 2020, OpenTelemetry Authors
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# 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 abc
+import enum
+
+import six
+
+import grpc
+
+
+class ActiveSpanSource(six.with_metaclass(abc.ABCMeta)):
+    """Provides a way to access an the active span."""
+
+    @abc.abstractmethod
+    def get_active_span(self):
+        """Identifies the active span.
+
+    Returns:
+      An object that implements the opentracing.Span interface.
+    """
+        raise NotImplementedError()
+
+
+class RpcInfo(six.with_metaclass(abc.ABCMeta)):
+    """Provides information for an RPC call.
+
+  Attributes:
+    full_method: A string of the full RPC method, i.e., /package.service/method.
+    metadata: The initial :term:`metadata`.
+    timeout: The length of time in seconds to wait for the computation to
+      terminate or be cancelled.
+    request: The RPC request or None for request-streaming RPCs.
+    response: The RPC response or None for response-streaming or erroring RPCs.
+    error: The RPC error or None for successful RPCs.
+  """
+
+
+class SpanDecorator(six.with_metaclass(abc.ABCMeta)):
+    """Provides a mechanism to add arbitrary tags/logs/etc to the
+    opentracing.Span associated with client and/or server RPCs."""
+
+    @abc.abstractmethod
+    def __call__(self, span, rpc_info):
+        """Customizes an RPC span.
+
+    Args:
+      span: The client-side or server-side opentracing.Span for the RPC.
+      rpc_info: An RpcInfo describing the RPC.
+    """
+        raise NotImplementedError()
+
+
+def open_tracing_client_interceptor(tracer,
+                                    active_span_source=None,
+                                    log_payloads=False,
+                                    span_decorator=None):
+    """Creates an invocation-side interceptor that can be use with gRPC to add
+    OpenTracing information.
+
+  Args:
+    tracer: An object implmenting the opentracing.Tracer interface.
+    active_span_source: An optional ActiveSpanSource to customize how the
+      active span is determined.
+    log_payloads: Indicates whether requests should be logged.
+    span_decorator: An optional SpanDecorator.
+
+  Returns:
+    An invocation-side interceptor object.
+  """
+    from grpc_opentracing import _client
+    return _client.OpenTracingClientInterceptor(tracer, active_span_source,
+                                                log_payloads, span_decorator)
+
+
+def open_tracing_server_interceptor(tracer,
+                                    log_payloads=False,
+                                    span_decorator=None):
+    """Creates a service-side interceptor that can be use with gRPC to add
+    OpenTracing information.
+
+  Args:
+    tracer: An object implmenting the opentracing.Tracer interface.
+    log_payloads: Indicates whether requests should be logged.
+    span_decorator: An optional SpanDecorator.
+
+  Returns:
+    A service-side interceptor object.
+  """
+    from grpc_opentracing import _server
+    return _server.OpenTracingServerInterceptor(tracer, log_payloads,
+                                                span_decorator)
+
+
+###################################  __all__  #################################
+
+__all__ = ('ActiveSpanSource', 'RpcInfo', 'SpanDecorator',
+           'open_tracing_client_interceptor',
+           'open_tracing_server_interceptor',)

ext/opentelemetry-ext-grpc/src/opentelemetry/ext/grpc/_client.py

@@ -0,0 +1,209 @@
+"""Implementation of the invocation-side open-tracing interceptor."""
+
+import sys
+import logging
+import time
+
+from six import iteritems
+
+import grpc
+from grpc_opentracing import grpcext
+from grpc_opentracing._utilities import get_method_type, get_deadline_millis,\
+    log_or_wrap_request_or_iterator, RpcInfo
+import opentracing
+from opentracing.ext import tags as ot_tags
+
+
+class _GuardedSpan(object):
+
+    def __init__(self, span):
+        self.span = span
+        self._engaged = True
+
+    def __enter__(self):
+        self.span.__enter__()
+        return self
+
+    def __exit__(self, *args, **kwargs):
+        if self._engaged:
+            return self.span.__exit__(*args, **kwargs)
+        else:
+            return False
+
+    def release(self):
+        self._engaged = False
+        return self.span
+
+
+def _inject_span_context(tracer, span, metadata):
+    headers = {}
+    try:
+        tracer.inject(span.context, opentracing.Format.HTTP_HEADERS, headers)
+    except (opentracing.UnsupportedFormatException,
+            opentracing.InvalidCarrierException,
+            opentracing.SpanContextCorruptedException) as e:
+        logging.exception('tracer.inject() failed')
+        span.log_kv({'event': 'error', 'error.object': e})
+        return metadata
+    metadata = () if metadata is None else tuple(metadata)
+    return metadata + tuple((k.lower(), v) for (k, v) in iteritems(headers))
+
+
+def _make_future_done_callback(span, rpc_info, log_payloads, span_decorator):
+
+    def callback(response_future):
+        with span:
+            code = response_future.code()
+            if code != grpc.StatusCode.OK:
+                span.set_tag('error', True)
+                error_log = {'event': 'error', 'error.kind': str(code)}
+                details = response_future.details()
+                if details is not None:
+                    error_log['message'] = details
+                span.log_kv(error_log)
+                rpc_info.error = code
+                if span_decorator is not None:
+                    span_decorator(span, rpc_info)
+                return
+            response = response_future.result()
+            rpc_info.response = response
+            if log_payloads:
+                span.log_kv({'response': response})
+            if span_decorator is not None:
+                span_decorator(span, rpc_info)
+
+    return callback
+
+
+class OpenTracingClientInterceptor(grpcext.UnaryClientInterceptor,
+                                   grpcext.StreamClientInterceptor):
+
+    def __init__(self, tracer, active_span_source, log_payloads,
+                 span_decorator):
+        self._tracer = tracer
+        self._active_span_source = active_span_source
+        self._log_payloads = log_payloads
+        self._span_decorator = span_decorator
+
+    def _start_span(self, method):
+        active_span_context = None
+        if self._active_span_source is not None:
+            active_span = self._active_span_source.get_active_span()
+            if active_span is not None:
+                active_span_context = active_span.context
+        tags = {
+            ot_tags.COMPONENT: 'grpc',
+            ot_tags.SPAN_KIND: ot_tags.SPAN_KIND_RPC_CLIENT
+        }
+        return self._tracer.start_span(
+            operation_name=method, child_of=active_span_context, tags=tags)
+
+    def _trace_result(self, guarded_span, rpc_info, result):
+        # If the RPC is called asynchronously, release the guard and add a callback
+        # so that the span can be finished once the future is done.
+        if isinstance(result, grpc.Future):
+            result.add_done_callback(
+                _make_future_done_callback(guarded_span.release(
+                ), rpc_info, self._log_payloads, self._span_decorator))
+            return result
+        response = result
+        # Handle the case when the RPC is initiated via the with_call
+        # method and the result is a tuple with the first element as the
+        # response.
+        # http://www.grpc.io/grpc/python/grpc.html#grpc.UnaryUnaryMultiCallable.with_call
+        if isinstance(result, tuple):
+            response = result[0]
+        rpc_info.response = response
+        if self._log_payloads:
+            guarded_span.span.log_kv({'response': response})
+        if self._span_decorator is not None:
+            self._span_decorator(guarded_span.span, rpc_info)
+        return result
+
+    def _start_guarded_span(self, *args, **kwargs):
+        return _GuardedSpan(self._start_span(*args, **kwargs))
+
+    def intercept_unary(self, request, metadata, client_info, invoker):
+        with self._start_guarded_span(client_info.full_method) as guarded_span:
+            metadata = _inject_span_context(self._tracer, guarded_span.span,
+                                            metadata)
+            rpc_info = RpcInfo(
+                full_method=client_info.full_method,
+                metadata=metadata,
+                timeout=client_info.timeout,
+                request=request)
+            if self._log_payloads:
+                guarded_span.span.log_kv({'request': request})
+            try:
+                result = invoker(request, metadata)
+            except:
+                e = sys.exc_info()[0]
+                guarded_span.span.set_tag('error', True)
+                guarded_span.span.log_kv({'event': 'error', 'error.object': e})
+                rpc_info.error = e
+                if self._span_decorator is not None:
+                    self._span_decorator(guarded_span.span, rpc_info)
+                raise
+            return self._trace_result(guarded_span, rpc_info, result)
+
+    # For RPCs that stream responses, the result can be a generator. To record
+    # the span across the generated responses and detect any errors, we wrap the
+    # result in a new generator that yields the response values.
+    def _intercept_server_stream(self, request_or_iterator, metadata,
+                                 client_info, invoker):
+        with self._start_span(client_info.full_method) as span:
+            metadata = _inject_span_context(self._tracer, span, metadata)
+            rpc_info = RpcInfo(
+                full_method=client_info.full_method,
+                metadata=metadata,
+                timeout=client_info.timeout)
+            if client_info.is_client_stream:
+                rpc_info.request = request_or_iterator
+            if self._log_payloads:
+                request_or_iterator = log_or_wrap_request_or_iterator(
+                    span, client_info.is_client_stream, request_or_iterator)
+            try:
+                result = invoker(request_or_iterator, metadata)
+                for response in result:
+                    if self._log_payloads:
+                        span.log_kv({'response': response})
+                    yield response
+            except:
+                e = sys.exc_info()[0]
+                span.set_tag('error', True)
+                span.log_kv({'event': 'error', 'error.object': e})
+                rpc_info.error = e
+                if self._span_decorator is not None:
+                    self._span_decorator(span, rpc_info)
+                raise
+            if self._span_decorator is not None:
+                self._span_decorator(span, rpc_info)
+
+    def intercept_stream(self, request_or_iterator, metadata, client_info,
+                         invoker):
+        if client_info.is_server_stream:
+            return self._intercept_server_stream(request_or_iterator, metadata,
+                                                 client_info, invoker)
+        with self._start_guarded_span(client_info.full_method) as guarded_span:
+            metadata = _inject_span_context(self._tracer, guarded_span.span,
+                                            metadata)
+            rpc_info = RpcInfo(
+                full_method=client_info.full_method,
+                metadata=metadata,
+                timeout=client_info.timeout,
+                request=request_or_iterator)
+            if self._log_payloads:
+                request_or_iterator = log_or_wrap_request_or_iterator(
+                    guarded_span.span, client_info.is_client_stream,
+                    request_or_iterator)
+            try:
+                result = invoker(request_or_iterator, metadata)
+            except:
+                e = sys.exc_info()[0]
+                guarded_span.span.set_tag('error', True)
+                guarded_span.span.log_kv({'event': 'error', 'error.object': e})
+                rpc_info.error = e
+                if self._span_decorator is not None:
+                    self._span_decorator(guarded_span.span, rpc_info)
+                raise
+            return self._trace_result(guarded_span, rpc_info, result)