Fix legacy envoy benchmark test and add openmetrics benchmark (#24080)

* Fix envoy bench test and add openmetrics benchmark

* setup check with dd_run_check

* fix license

Author: sarah-witt

envoy/tests/legacy/test_bench.py

@@ -24,7 +24,7 @@ def test_fixture(benchmark, fixture_path, mock_http_response):
     instance = INSTANCES['main']
     c = Envoy('envoy', {}, [instance])
 
-    mock_http_response(file_path=fixture_path('multiple_services'))
+    mock_http_response(file_path=fixture_path('legacy/multiple_services'))
 
     # Run once to get logging of unknown metrics out of the way.
     c.check(instance)

envoy/tests/test_bench.py

@@ -0,0 +1,18 @@
+# (C) Datadog, Inc. 2026-present
+# All rights reserved
+# Licensed under a 3-clause BSD style license (see LICENSE)
+
+from datadog_checks.envoy import Envoy
+
+from .common import DEFAULT_INSTANCE, get_fixture_path
+
+OPENMETRICS_FIXTURE = get_fixture_path('./openmetrics/openmetrics.txt')
+
+
+def test_openmetrics_check(benchmark, dd_run_check, mock_http_response):
+    mock_http_response(file_path=OPENMETRICS_FIXTURE)
+
+    c = Envoy('envoy', {}, [DEFAULT_INSTANCE])
+    dd_run_check(c)
+
+    benchmark(c.check, DEFAULT_INSTANCE)