Batch exporting spans once a while (#63)

Author: liyanhui1228

trace/opencensus/trace/exporters/base.py

@@ -20,7 +20,13 @@ class Exporter(object):
 
     Subclasses of :class:`Exporter` must override :meth:`export`.
     """
+    def emit(self, trace):
+        """Emit the trace."""
+        raise NotImplementedError
 
     def export(self, trace):
-        """Export the trace."""
+        """Export the trace. Send trace to transport, and transport will call
+        exporter.emit() to actually send the trace to the specified tracing
+        backend.
+        """
         raise NotImplementedError

trace/opencensus/trace/exporters/file_exporter.py

@@ -17,6 +17,7 @@
 import json
 
 from opencensus.trace.exporters import base
+from opencensus.trace.exporters.transports import sync
 
 DEFAULT_FILENAME = 'opencensus-traces.json'
 
@@ -25,16 +26,28 @@ class FileExporter(base.Exporter):
     """
     :type file_name: str
     :param file_name: The name of the output file.
+
+    :type transport: :class:`type`
+    :param transport: Class for creating new transport objects. It should
+                      extend from the base :class:`.Transport` type and
+                      implement :meth`.Transport.export`. Defaults to
+                      :class:`.SyncTransport`. The other option is
+                      :class:`.BackgroundThreadTransport`.
     """
 
-    def __init__(self, file_name=DEFAULT_FILENAME):
+    def __init__(self, file_name=DEFAULT_FILENAME,
+                 transport=sync.SyncTransport):
         self.file_name = file_name
+        self.transport = transport(self)
 
-    def export(self, trace):
+    def emit(self, trace):
         """
         :type trace: dict
         :param trace: Trace collected.
         """
         with open(self.file_name, 'w+') as file:
             trace_str = json.dumps(trace)
             file.write(trace_str)
+
+    def export(self, trace):
+        self.transport.export(trace)

trace/opencensus/trace/exporters/logging_exporter.py

@@ -17,6 +17,7 @@
 import logging
 
 from opencensus.trace.exporters import base
+from opencensus.trace.exporters.transports import sync
 
 
 class LoggingExporter(base.Exporter):
@@ -26,6 +27,13 @@ class LoggingExporter(base.Exporter):
     :type handler: :class:`logging.handler`
     :param handler: the handler to attach to the global handler
 
+    :type transport: :class:`type`
+    :param transport: Class for creating new transport objects. It should
+                      extend from the base :class:`.Transport` type and
+                      implement :meth`.Transport.export`. Defaults to
+                      :class:`.SyncTransport`. The other option is
+                      :class:`.BackgroundThreadTransport`.
+
     Example:
 
     .. code-block:: python
@@ -44,7 +52,7 @@ class LoggingExporter(base.Exporter):
     will be exported to logging when finished.
     """
 
-    def __init__(self, handler=None):
+    def __init__(self, handler=None, transport=sync.SyncTransport):
         self.logger = logging.getLogger()
 
         if handler is None:
@@ -53,10 +61,14 @@ def __init__(self, handler=None):
         self.handler = handler
         self.logger.addHandler(handler)
         self.logger.setLevel(logging.INFO)
+        self.transport = transport(self)
 
-    def export(self, trace):
+    def emit(self, trace):
         """
         :type traces: dict
         :param traces: Trace collected.
         """
         self.logger.info(trace)
+
+    def export(self, trace):
+        self.transport.export(trace)

trace/opencensus/trace/exporters/print_exporter.py

@@ -15,10 +15,23 @@
 """Export the trace spans by printing them out."""
 
 from opencensus.trace.exporters import base
+from opencensus.trace.exporters.transports import sync
 
 
 class PrintExporter(base.Exporter):
-    def export(self, trace):
+    """Export the spans by printing them.
+
+    :type transport: :class:`type`
+    :param transport: Class for creating new transport objects. It should
+                      extend from the base :class:`.Transport` type and
+                      implement :meth`.Transport.export`. Defaults to
+                      :class:`.SyncTransport`. The other option is
+                      :class:`.BackgroundThreadTransport`.
+    """
+    def __init__(self, transport=sync.SyncTransport):
+        self.transport = transport(self)
+
+    def emit(self, trace):
         """export the traces by printing it out.
 
         :type trace: dict
@@ -29,3 +42,6 @@ def export(self, trace):
         """
         print(trace)
         return trace
+
+    def export(self, trace):
+        self.transport.export(trace)

trace/opencensus/trace/exporters/stackdriver_exporter.py

@@ -15,6 +15,7 @@
 import os
 
 from opencensus.trace.exporters import base
+from opencensus.trace.exporters.transports import sync
 
 from google.cloud.trace.client import Client
 
@@ -73,23 +74,41 @@ def is_gae_environment():
 class StackdriverExporter(base.Exporter):
     """A exporter that send traces and trace spans to Google Cloud Stackdriver
     Trace.
+
+    :type client: :class: `~google.cloud.trace.client.Client`
+    :param client: Stackdriver Trace client.
+
+    :type project_id: str
+    :param project_id: project_id to create the Trace client.
+
+    :type transport: :class:`type`
+    :param transport: Class for creating new transport objects. It should
+                      extend from the base :class:`.Transport` type and
+                      implement :meth`.Transport.export`. Defaults to
+                      :class:`.SyncTransport`. The other option is
+                      :class:`.BackgroundThreadTransport`.
     """
-    def __init__(self, client=None, project_id=None):
+    def __init__(self, client=None, project_id=None,
+                 transport=sync.SyncTransport):
         # The client will handler the case when project_id is None
         if client is None:
             client = Client(project=project_id)
 
         self.client = client
         self.project_id = client.project
+        self.transport = transport(self)
 
-    def export(self, trace):
+    def emit(self, trace):
         """
         :type trace: dict
         :param trace: Trace collected.
         """
         stackdriver_traces = self.translate_to_stackdriver(trace)
         self.client.patch_traces(stackdriver_traces)
 
+    def export(self, trace):
+        self.transport.export(trace)
+
     def translate_to_stackdriver(self, trace):
         """
         :type trace: dict

trace/opencensus/trace/exporters/transports/__init__.py

@@ -0,0 +1,13 @@
+# Copyright 2017, OpenCensus 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.