Update WSGI implementation

Author: macieyng

instrumentation/opentelemetry-instrumentation-wsgi/src/opentelemetry/instrumentation/wsgi/__init__.py

@@ -440,8 +440,12 @@ def add_response_attributes(
 
 
 def get_default_span_name(environ):
-    """Default implementation for name_callback, returns HTTP {METHOD_NAME}."""
-    return f"HTTP {environ.get('REQUEST_METHOD', '')}".strip()
+    """Default implementation for name_callback, returns `{METHOD_NAME}`."""
+    method = environ.get("REQUEST_METHOD", "").strip()
+    route = environ.get("PATH_INFO", "").strip()
+    if route:
+        return f"{method} {route}"
+    return method
 
 
 class OpenTelemetryMiddleware:

instrumentation/opentelemetry-instrumentation-wsgi/tests/test_wsgi_middleware.py

@@ -128,7 +128,7 @@ def validate_response(
         self,
         response,
         error=None,
-        span_name="HTTP GET",
+        span_name="GET /",
         http_method="GET",
         span_attributes=None,
         response_headers=None,
@@ -284,12 +284,14 @@ def test_wsgi_metrics(self):
                             )
         self.assertTrue(number_data_point_seen and histogram_data_point_seen)
 
-    def test_default_span_name_missing_request_method(self):
-        """Test that default span_names with missing request method."""
-        self.environ.pop("REQUEST_METHOD")
+    # Question: How often request method can be lost?
+    def test_default_span_name_missing_path_info(self):
+        """Test that default span_names with missing path info."""
+        self.environ.pop("PATH_INFO")
+        method = self.environ.get("REQUEST_METHOD", "").strip()
         app = otel_wsgi.OpenTelemetryMiddleware(simple_wsgi)
         response = app(self.environ, self.start_response)
-        self.validate_response(response, span_name="HTTP", http_method=None)
+        self.validate_response(response, span_name=method)
 
 
 class TestWsgiAttributes(unittest.TestCase):
@@ -455,7 +457,7 @@ def validate_response(
         response,
         exporter,
         error=None,
-        span_name="HTTP GET",
+        span_name="GET /",
         http_method="GET",
     ):
         while True: