chore(functions/logging): exclude trace code from sample (GoogleCloudPlatform#6648)

Ace Nassri · dinagraves · web-flow · commit e9312003cbe3 · 2022-01-13T12:36:28.000-08:00
* Apply Adam's suggested fix

* locals -&gt; globals

* Add tests + confirm it works on GCF

* Run black

* Remove unused region tag

Co-authored-by: Dina Graves Portman &lt;dinagraves@google.com&gt;
diff --git a/run/logging-manual/e2e_test.py b/run/logging-manual/e2e_test.py
@@ -152,7 +152,7 @@ def test_end_to_end(service_url_auth_token, deployed_service):
         total=3,
         status_forcelist=[400, 401, 403, 500, 502, 503, 504],
         allowed_methods=["GET", "POST"],
-        backoff_factor=3
+        backoff_factor=3,
     )
     adapter = HTTPAdapter(max_retries=retry_strategy)
 
@@ -187,7 +187,9 @@ def test_end_to_end(service_url_auth_token, deployed_service):
     # Retry a maximum number of 10 times to find results in stackdriver
     found = False
     for x in range(10):
-        iterator = client.list_log_entries({"resource_names": resource_names, "filter": filters})
+        iterator = client.list_log_entries(
+            {"resource_names": resource_names, "filter": filters}
+        )
         for entry in iterator:
             found = True
             # If there are any results, exit loop
diff --git a/run/logging-manual/main.py b/run/logging-manual/main.py
@@ -12,9 +12,12 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+# [START cloudrun_manual_logging]
 import json
 import os
 
+# [END cloudrun_manual_logging]
+
 from flask import Flask, request
 
 
@@ -29,21 +32,24 @@ def index():
     PROJECT = os.environ["GOOGLE_CLOUD_PROJECT"]
 
     # [START cloudrun_manual_logging]
-    # [START run_manual_logging]
     # Uncomment and populate this variable in your code:
     # PROJECT = 'The project ID of your Cloud Run service';
 
     # Build structured log messages as an object.
     global_log_fields = {}
 
     # Add log correlation to nest all log messages.
-    trace_header = request.headers.get("X-Cloud-Trace-Context")
-
-    if trace_header and PROJECT:
-        trace = trace_header.split("/")
-        global_log_fields[
-            "logging.googleapis.com/trace"
-        ] = f"projects/{PROJECT}/traces/{trace[0]}"
+    # This is only relevant in HTTP-based contexts, and is ignored elsewhere.
+    # (In particular, non-HTTP-based Cloud Functions.)
+    request_is_defined = "request" in globals() or "request" in locals()
+    if request_is_defined and request:
+        trace_header = request.headers.get("X-Cloud-Trace-Context")
+
+        if trace_header and PROJECT:
+            trace = trace_header.split("/")
+            global_log_fields[
+                "logging.googleapis.com/trace"
+            ] = f"projects/{PROJECT}/traces/{trace[0]}"
 
     # Complete a structured log entry.
     entry = dict(
@@ -55,7 +61,6 @@ def index():
     )
 
     print(json.dumps(entry))
-    # [END run_manual_logging]
     # [END cloudrun_manual_logging]
 
     return "Hello Logger!"
diff --git a/run/logging-manual/main_test.py b/run/logging-manual/main_test.py
@@ -42,3 +42,11 @@ def test_with_cloud_headers(client, capsys):
     out, _ = capsys.readouterr()
     print(out)
     assert "trace" in out
+
+
+def test_no_http_request(capsys):
+    main.index()
+
+    out, _ = capsys.readouterr()
+    print(out)
+    assert "trace" not in out
