Update Flask html meta helper (#2203)

Update Flask html meta helper to use the new top level API for getting sentry-trace and baggage information.

sentry_sdk/hub.py

@@ -805,7 +805,10 @@ def trace_propagation_meta(self, span=None):
 
         baggage = self.get_baggage()
         if baggage is not None:
-            meta += '<meta name="%s" content="%s">' % (BAGGAGE_HEADER_NAME, baggage)
+            meta += '<meta name="%s" content="%s">' % (
+                BAGGAGE_HEADER_NAME,
+                baggage,
+            )
 
         return meta
 

sentry_sdk/integrations/flask.py

@@ -6,7 +6,7 @@
 from sentry_sdk.integrations._wsgi_common import RequestExtractor
 from sentry_sdk.integrations.wsgi import SentryWsgiMiddleware
 from sentry_sdk.scope import Scope
-from sentry_sdk.tracing import SENTRY_TRACE_HEADER_NAME, SOURCE_FOR_STYLE
+from sentry_sdk.tracing import SOURCE_FOR_STYLE
 from sentry_sdk.utils import (
     capture_internal_exceptions,
     event_from_exception,
@@ -93,22 +93,13 @@ def sentry_patched_wsgi_app(self, environ, start_response):
 
 def _add_sentry_trace(sender, template, context, **extra):
     # type: (Flask, Any, Dict[str, Any], **Any) -> None
-
     if "sentry_trace" in context:
         return
 
-    sentry_span = Hub.current.scope.span
-    context["sentry_trace"] = (
-        Markup(
-            '<meta name="%s" content="%s" />'
-            % (
-                SENTRY_TRACE_HEADER_NAME,
-                sentry_span.to_traceparent(),
-            )
-        )
-        if sentry_span
-        else ""
-    )
+    hub = Hub.current
+    trace_meta = Markup(hub.trace_propagation_meta())
+    context["sentry_trace"] = trace_meta  # for backwards compatibility
+    context["sentry_trace_meta"] = trace_meta
 
 
 def _set_transaction_name_and_source(scope, transaction_style, request):

tests/integrations/flask/test_flask.py

@@ -806,22 +806,33 @@ def dispatch_request(self):
     assert event["transaction"] == "hello_class"
 
 
-def test_sentry_trace_context(sentry_init, app, capture_events):
-    sentry_init(integrations=[flask_sentry.FlaskIntegration()])
+@pytest.mark.parametrize(
+    "template_string", ["{{ sentry_trace }}", "{{ sentry_trace_meta }}"]
+)
+def test_sentry_trace_context(sentry_init, app, capture_events, template_string):
+    sentry_init(integrations=[flask_sentry.FlaskIntegration()], traces_sample_rate=1.0)
     events = capture_events()
 
     @app.route("/")
     def index():
-        sentry_span = Hub.current.scope.span
-        capture_message(sentry_span.to_traceparent())
-        return render_template_string("{{ sentry_trace }}")
+        hub = Hub.current
+        capture_message(hub.get_traceparent() + "\n" + hub.get_baggage())
+        return render_template_string(template_string)
 
     with app.test_client() as client:
         response = client.get("/")
         assert response.status_code == 200
-        assert response.data.decode(
-            "utf-8"
-        ) == '<meta name="sentry-trace" content="%s" />' % (events[0]["message"],)
+
+        rendered_meta = response.data.decode("utf-8")
+        traceparent, baggage = events[0]["message"].split("\n")
+        expected_meta = (
+            '<meta name="sentry-trace" content="%s"><meta name="baggage" content="%s">'
+            % (
+                traceparent,
+                baggage,
+            )
+        )
+        assert rendered_meta == expected_meta
 
 
 def test_dont_override_sentry_trace_context(sentry_init, app):