feat: Add OpenTelemetry publish sample

samples/snippets/publisher.py

@@ -170,6 +170,87 @@ def delete_topic(project_id: str, topic_id: str) -> None:
     # [END pubsub_delete_topic]
 
 
+def pubsub_publish_otel_tracing(
+    topic_project_id: str, trace_project_id: str, topic_id: str
+) -> None:
+    """
+    Publish to `topic_id` in `topic_project_id` with OpenTelemetry enabled.
+    Export the OpenTelemetry traces to Google Cloud Trace in project
+    `trace_project_id`
+
+    Args:
+        topic_project_id: project ID of the topic to publish to.
+        trace_project_id: project ID to export Cloud Trace to.
+        topic_id: topic ID to publish to.
+
+    Returns:
+        None
+    """
+    # [START pubsub_publish_otel_tracing]
+
+    from opentelemetry import trace
+    from opentelemetry.sdk.trace import TracerProvider
+    from opentelemetry.sdk.trace.export import (
+        BatchSpanProcessor,
+    )
+    from opentelemetry.exporter.cloud_trace import CloudTraceSpanExporter
+    from opentelemetry.sdk.trace.sampling import TraceIdRatioBased, ParentBased
+
+    from google.cloud.pubsub_v1 import PublisherClient
+    from google.cloud.pubsub_v1.types import PublisherOptions
+
+    # TODO(developer)
+    # topic_project_id = "your-topic-project-id"
+    # trace_project_id = "your-trace-project-id"
+    # topic_id = "your-topic-id"
+
+    # In this sample, we use a Google Cloud Trace to export the OpenTelemetry
+    # traces: https://cloud.google.com/trace/docs/setup/python-ot
+    # Choose and configure the exporter for your set up accordingly.
+
+    # Sample 1 in every 1000 traces.
+    sampler = ParentBased(root=TraceIdRatioBased(1 / 1000))
+    trace.set_tracer_provider(TracerProvider(sampler=sampler))
+
+    # Export to Google Trace.
+    cloud_trace_exporter = CloudTraceSpanExporter(
+        project_id=trace_project_id,
+    )
+    trace.get_tracer_provider().add_span_processor(
+        BatchSpanProcessor(cloud_trace_exporter)
+    )
+
+    # Set the `enable_open_telemetry_tracing` option to True when creating
+    # the publisher client. This in itself is necessary and sufficient for
+    # the library to export OpenTelemetry traces. However, where the traces
+    # must be exported to needs to be configured based on your OpenTelemetry
+    # set up. Refer: https://opentelemetry.io/docs/languages/python/exporters/
+    publisher = PublisherClient(
+        publisher_options=PublisherOptions(
+            enable_open_telemetry_tracing=True,
+        ),
+    )
+
+    # The `topic_path` method creates a fully qualified identifier
+    # in the form `projects/{project_id}/topics/{topic_id}`
+    topic_path = publisher.topic_path(topic_project_id, topic_id)
+
+    tracer = trace.get_tracer("google.cloud.pubsub_v1.publisher")
+    with tracer.start_as_current_span("parent cloud trace span"):
+        # Publish messages.
+        for n in range(1, 10000):
+            data_str = f"Message number {n}"
+            # Data must be a bytestring
+            data = data_str.encode("utf-8")
+            # When you publish a message, the client returns a future.
+            future = publisher.publish(topic_path, data)
+            print(future.result())
+
+        print(f"Published messages to {topic_path}.")
+
+    # [END pubsub_publish_otel_tracing]
+
+
 def publish_messages(project_id: str, topic_id: str) -> None:
     """Publishes multiple messages to a Pub/Sub topic."""
     # [START pubsub_quickstart_publisher]
@@ -522,6 +603,13 @@ def detach_subscription(project_id: str, subscription_id: str) -> None:
     create_parser = subparsers.add_parser("create", help=create_topic.__doc__)
     create_parser.add_argument("topic_id")
 
+    pubsub_publish_otel_tracing_parser = subparsers.add_parser(
+        "pubsub-publish-otel-tracing", help=pubsub_publish_otel_tracing.__doc__
+    )
+    pubsub_publish_otel_tracing_parser.add_argument("topic_project_id")
+    pubsub_publish_otel_tracing_parser.add_argument("trace_project_id")
+    pubsub_publish_otel_tracing_parser.add_argument("topic_id")
+
     create_topic_with_kinesis_ingestion_parser = subparsers.add_parser(
         "create_kinesis_ingestion", help=create_topic_with_kinesis_ingestion.__doc__
     )
@@ -638,3 +726,7 @@ def detach_subscription(project_id: str, subscription_id: str) -> None:
         resume_publish_with_ordering_keys(args.project_id, args.topic_id)
     elif args.command == "detach-subscription":
         detach_subscription(args.project_id, args.subscription_id)
+    elif args.command == "pubsub-publish-otel-tracing":
+        pubsub_publish_otel_tracing(
+            args.topic_project_id, args.trace_project_id, args.topic_id
+        )

samples/snippets/publisher_test.py

@@ -17,6 +17,7 @@
 import typing
 from typing import Any, Callable, cast, Iterator, TypeVar, Union
 import uuid
+import sys
 
 from _pytest.capture import CaptureFixture
 import backoff
@@ -209,6 +210,18 @@ def test_list(topic_path: str, capsys: CaptureFixture[str]) -> None:
     assert topic_path in out
 
 
+@pytest.mark.skipif(
+    sys.version_info < (3, 8),
+    reason="Open Telemetry not supported below Python version 3.8",
+)
+def test_pubsub_publish_otel_tracing(
+    capsys: CaptureFixture[str],
+) -> None:
+    publisher.pubsub_publish_otel_tracing(PROJECT_ID, PROJECT_ID, TOPIC_ID)
+    out, _ = capsys.readouterr()
+    assert f"Published messages to {topic_path}." in out
+
+
 def test_publish(topic_path: str, capsys: CaptureFixture[str]) -> None:
     publisher.publish_messages(PROJECT_ID, TOPIC_ID)
 

samples/snippets/requirements.txt

@@ -3,3 +3,6 @@ avro==1.12.0
 protobuf===4.24.4; python_version == '3.7'
 protobuf==5.28.0; python_version >= '3.8'
 avro==1.12.0
+opentelemetry-api==1.22.0
+opentelemetry-sdk==1.22.0
+opentelemetry-exporter-gcp-trace==1.7.0