Make the service name configurable for Jaeger in flask and django (#352)

* Make the service name configurable for Jaeger in flask and django

* Fix typo

* Fix a bug and added tests

Author: geobeau

opencensus/trace/ext/django/middleware.py

@@ -153,6 +153,11 @@ def __init__(self, get_response=None):
                 service_name=_service_name,
                 endpoint=_endpoint,
                 transport=transport)
+        elif self._exporter.__name__ == 'JaegerExporter':
+            _service_name = self._get_service_name(settings.params)
+            self.exporter = self._exporter(
+                service_name=_service_name,
+                transport=transport)
         else:
             self.exporter = self._exporter(transport=transport)
 

opencensus/trace/ext/flask/flask_middleware.py

@@ -157,6 +157,11 @@ def init_app(self, app):
                 service_name=_service_name,
                 endpoint=_endpoint,
                 transport=transport)
+        elif self.exporter.__name__ == 'JaegerExporter':
+            _service_name = self._get_service_name(params)
+            self.exporter = self.exporter(
+                service_name=_service_name,
+                transport=transport)
         else:
             self.exporter = self.exporter(transport=transport)
 

tests/unit/trace/ext/django/test_middleware.py

@@ -22,6 +22,7 @@
 from opencensus.trace import span as span_module
 from opencensus.trace.exporters import print_exporter
 from opencensus.trace.exporters import zipkin_exporter
+from opencensus.trace.exporters import jaeger_exporter
 from opencensus.trace.exporters.ocagent import trace_exporter
 from opencensus.trace.exporters.transports import sync
 from opencensus.trace.ext import utils
@@ -133,6 +134,43 @@ def test_constructor_zipkin(self):
         self.assertEqual(middleware.exporter.host_name, host_name)
         self.assertEqual(middleware.exporter.port, port)
 
+    def test_constructor_jaeger(self):
+        from opencensus.trace.ext.django import middleware
+
+        service_name = 'test_service'
+        params = {
+            'SERVICE_NAME': service_name,
+            'TRANSPORT':
+                'opencensus.trace.exporters.transports.sync.SyncTransport',
+        }
+
+        patch_jaeger = mock.patch(
+            'opencensus.trace.ext.django.config.settings.EXPORTER',
+            jaeger_exporter.JaegerExporter)
+
+        patch_params = mock.patch(
+            'opencensus.trace.ext.django.config.settings.params',
+            params)
+
+        with patch_jaeger, patch_params:
+            middleware = middleware.OpencensusMiddleware()
+
+        self.assertIs(middleware._sampler, always_on.AlwaysOnSampler)
+        self.assertIs(
+            middleware._exporter, jaeger_exporter.JaegerExporter)
+        self.assertIs(
+            middleware._propagator,
+            google_cloud_format.GoogleCloudFormatPropagator)
+
+        assert isinstance(middleware.sampler, always_on.AlwaysOnSampler)
+        assert isinstance(
+            middleware.exporter, jaeger_exporter.JaegerExporter)
+        assert isinstance(
+            middleware.propagator,
+            google_cloud_format.GoogleCloudFormatPropagator)
+
+        self.assertEqual(middleware.exporter.service_name, service_name)
+
     def test_constructor_zipkin_service_name_param(self):
         from opencensus.trace.ext.django import middleware
 

tests/unit/trace/ext/flask/test_flask_middleware.py

@@ -27,7 +27,7 @@
 from opencensus.trace import stack_trace
 from opencensus.trace import status
 from opencensus.trace.exporters import print_exporter, stackdriver_exporter, \
-    zipkin_exporter
+    zipkin_exporter, jaeger_exporter
 from opencensus.trace.exporters.ocagent import trace_exporter
 from opencensus.trace.ext.flask import flask_middleware
 from opencensus.trace.propagation import google_cloud_format
@@ -202,6 +202,31 @@ def test_init_app_config_zipkin_exporter_service_name_param(self):
         self.assertEqual(middleware.exporter.host_name, host_name)
         self.assertEqual(middleware.exporter.port, port)
 
+    def test_init_app_config_jaeger_exporter(self):
+        service_name = 'foo'
+        app = mock.Mock()
+        app.config = {
+            'OPENCENSUS_TRACE': {
+                'SAMPLER': ProbabilitySampler,
+                'EXPORTER': jaeger_exporter.JaegerExporter,
+                'PROPAGATOR': google_cloud_format.GoogleCloudFormatPropagator,
+            },
+            'OPENCENSUS_TRACE_PARAMS': {
+                'SERVICE_NAME': service_name,
+            },
+        }
+
+        middleware = flask_middleware.FlaskMiddleware()
+        middleware.init_app(app)
+
+        self.assertIs(middleware.app, app)
+        self.assertTrue(app.before_request.called)
+        self.assertTrue(app.after_request.called)
+
+        assert isinstance(
+            middleware.exporter, jaeger_exporter.JaegerExporter)
+        self.assertEqual(middleware.exporter.service_name, service_name)
+
     def test_init_app_config_ocagent_trace_exporter(self):
         app = mock.Mock()
         app.config = {