Use default TraceContext propagator in example (open-telemetry#188)

examples/opentelemetry-example-app/src/opentelemetry_example_app/flask_example.py

@@ -21,9 +21,8 @@
 import requests
 
 import opentelemetry.ext.http_requests
-from opentelemetry import propagators, trace
+from opentelemetry import trace
 from opentelemetry.ext.flask import instrument_app
-from opentelemetry.sdk.context.propagation.b3_format import B3Format
 from opentelemetry.sdk.trace import TracerSource
 
 
@@ -43,17 +42,14 @@ def configure_opentelemetry(flask_app: flask.Flask):
     """
     # Start by configuring all objects required to ensure
     # a complete end to end workflow.
-    # the preferred implementation of these objects must be set,
+    # The preferred implementation of these objects must be set,
     # as the opentelemetry-api defines the interface with a no-op
     # implementation.
     trace.set_preferred_tracer_source_implementation(lambda _: TracerSource())
+
     # Next, we need to configure how the values that are used by
     # traces and metrics are propagated (such as what specific headers
     # carry this value).
-
-    # TBD: can remove once default TraceContext propagators are installed.
-    propagators.set_global_httptextformat(B3Format())
-
     # Integrations are the glue that binds the OpenTelemetry API
     # and the frameworks and libraries that are used together, automatically
     # creating Spans and propagating context as appropriate.

examples/opentelemetry-example-app/tests/test_flask_example.py

@@ -20,8 +20,8 @@
 from werkzeug.wrappers import BaseResponse
 
 import opentelemetry_example_app.flask_example as flask_example
-from opentelemetry.sdk import trace
-from opentelemetry.sdk.context.propagation import b3_format
+from opentelemetry import trace
+from opentelemetry.sdk import trace as trace_sdk
 
 
 class TestFlaskExample(unittest.TestCase):
@@ -46,7 +46,7 @@ def tearDown(self):
         self.send_patcher.stop()
 
     def test_full_path(self):
-        trace_id = trace.generate_trace_id()
+        trace_id = trace_sdk.generate_trace_id()
         # We need to use the Werkzeug test app because
         # The headers are injected at the wsgi layer.
         # The flask test app will not include these, and
@@ -56,18 +56,17 @@ def test_full_path(self):
         client.get(
             "/",
             headers={
-                "x-b3-traceid": b3_format.format_trace_id(trace_id),
-                "x-b3-spanid": b3_format.format_span_id(
-                    trace.generate_span_id()
-                ),
-                "x-b3-sampled": "1",
+                "traceparent": "00-{:032x}-{:016x}-{:02x}".format(
+                    trace_id,
+                    trace_sdk.generate_span_id(),
+                    trace.TraceOptions.SAMPLED,
+                )
             },
         )
         # assert the http request header was propagated through.
         prepared_request = self.send.call_args[0][1]
         headers = prepared_request.headers
-        for required_header in {"x-b3-traceid", "x-b3-spanid", "x-b3-sampled"}:
-            self.assertIn(required_header, headers)
-        self.assertEqual(
-            headers["x-b3-traceid"], b3_format.format_trace_id(trace_id)
+        self.assertRegex(
+            headers["traceparent"],
+            r"00-{:032x}-[0-9a-f]{{16}}-01".format(trace_id),
         )