chore(otel): raise exception if exporter unavailable (#234)

Author: jer96

src/strands/telemetry/tracer.py

@@ -219,7 +219,7 @@ def _initialize_tracer(self) -> None:
             except Exception as e:
                 logger.exception("error=<%s> | Failed to configure OTLP exporter", e)
         elif self.otlp_endpoint and self.tracer_provider:
-            logger.warning(OTEL_EXPORTER_MODULE_ERROR)
+            raise ModuleNotFoundError(OTEL_EXPORTER_MODULE_ERROR)
 
         # Set as global tracer provider
         trace_api.set_tracer_provider(self.tracer_provider)

tests/strands/telemetry/test_tracer.py

@@ -531,6 +531,33 @@ def test_initialize_tracer_with_invalid_otlp_endpoint(
     mock_set_tracer_provider.assert_called_once_with(mock_tracer_provider.return_value)
 
 
+def test_initialize_tracer_with_missing_module(
+    mock_is_initialized, mock_tracer_provider, mock_set_tracer_provider, mock_resource
+):
+    """Test initializing the tracer when the OTLP exporter module is missing."""
+    mock_is_initialized.return_value = False
+
+    mock_resource_instance = mock.MagicMock()
+    mock_resource.create.return_value = mock_resource_instance
+
+    # Initialize Tracer with OTLP endpoint but missing module
+    with (
+        mock.patch("strands.telemetry.tracer.HAS_OTEL_EXPORTER_MODULE", False),
+        pytest.raises(ModuleNotFoundError) as excinfo,
+    ):
+        Tracer(otlp_endpoint="http://test-endpoint")
+
+    # Verify the error message
+    assert "opentelemetry-exporter-otlp-proto-http not detected" in str(excinfo.value)
+    assert "otel http exporting is currently DISABLED" in str(excinfo.value)
+
+    # Verify the tracer provider was created with correct resource
+    mock_tracer_provider.assert_called_once_with(resource=mock_resource_instance)
+
+    # Verify set_tracer_provider was not called since an exception was raised
+    mock_set_tracer_provider.assert_not_called()
+
+
 def test_initialize_tracer_with_custom_tracer_provider(mock_get_tracer_provider, mock_resource):
     """Test initializing the tracer with NoOpTracerProvider."""
     mock_is_initialized.return_value = True