make sure _span_holder is reset

strawberry/extensions/tracing/opentelemetry.py

@@ -37,7 +37,7 @@
 
 class OpenTelemetryExtension(SchemaExtension):
     _arg_filter: Optional[ArgFilter]
-    _span_holder: Dict[LifecycleStep, Span] = dict()
+    _span_holder: Dict[LifecycleStep, Span]
     _tracer: Tracer
 
     def __init__(
@@ -48,6 +48,7 @@ def __init__(
     ) -> None:
         self._arg_filter = arg_filter
         self._tracer = trace.get_tracer("strawberry")
+        self._span_holder = dict()
         if execution_context:
             self.execution_context = execution_context
 

tests/extensions/tracing/test_opentelemetry.py

@@ -0,0 +1,24 @@
+from unittest.mock import Mock
+
+from opentelemetry.trace import Span
+
+from strawberry.extensions import LifecycleStep
+from strawberry.extensions.tracing.opentelemetry import (
+    OpenTelemetryExtension,
+    OpenTelemetryExtensionSync,
+)
+
+
+def test_span_holder_initialization():
+    extension = OpenTelemetryExtension()
+    assert extension._span_holder == {}
+    extension._span_holder[LifecycleStep.OPERATION] = Mock(spec=Span)
+    extension = OpenTelemetryExtension()
+    assert extension._span_holder == {}
+
+def test_span_holder_initialization_sync():
+    extension = OpenTelemetryExtensionSync()
+    assert extension._span_holder == {}
+    extension._span_holder[LifecycleStep.OPERATION] = Mock(spec=Span)
+    extension = OpenTelemetryExtensionSync()
+    assert extension._span_holder == {}