Fixes issues #42897 - TypeError in _transmit_from_storage: LocalFileBlob.get() returns None but code expects iterable (#42951)

* Fixes issues-42897, return type None handled in _transmit_from_storage

* Updated CHANGELOG

* Moved CHANGELOG to Bugs Fixed

* Trigger CI/CD pipeline

Author: rads-1996

sdk/monitor/azure-monitor-opentelemetry-exporter/CHANGELOG.md

@@ -7,6 +7,8 @@
 ### Breaking Changes
 
 ### Bugs Fixed
+- Fixes issues #42897 - TypeError in _transmit_from_storage: LocalFileBlob.get() returns None
+  ([#42897](https://github.com/Azure/azure-sdk-for-python/pull/42951))
 
 ### Other Changes
 
@@ -29,6 +31,9 @@
   ([#42655](https://github.com/Azure/azure-sdk-for-python/pull/42655))
 - Customer Facing SDKStats: Added telemetry_success field to dropped items as per [Spec] - https://github.com/aep-health-and-standards/Telemetry-Collection-Spec/pull/606
   ([#42846](https://github.com/Azure/azure-sdk-for-python/pull/42846))
+### Breaking Changes
+
+### Bugs Fixed
 - Customer Facing SDKStats: Refactor to use `Manager` and `Singleton` pattern
   ([#42969](https://github.com/Azure/azure-sdk-for-python/pull/42969))
 

sdk/monitor/azure-monitor-opentelemetry-exporter/azure/monitor/opentelemetry/exporter/export/_base.py

@@ -202,11 +202,16 @@ def _transmit_from_storage(self) -> None:
             # give a few more seconds for blob lease operation
             # to reduce the chance of race (for perf consideration)
             if blob.lease(self._timeout + 5):
-                envelopes = [_format_storage_telemetry_item(TelemetryItem.from_dict(x)) for x in blob.get()]
-                result = self._transmit(envelopes)
-                if result == ExportResult.FAILED_RETRYABLE:
-                    blob.lease(1)
+                blob_data = blob.get()
+                if blob_data is not None:
+                    envelopes = [_format_storage_telemetry_item(TelemetryItem.from_dict(x)) for x in blob_data]
+                    result = self._transmit(envelopes)
+                    if result == ExportResult.FAILED_RETRYABLE:
+                        blob.lease(1)
+                    else:
+                        blob.delete()
                 else:
+                    # If blob.get() returns None, delete the corrupted blob
                     blob.delete()
 
 

sdk/monitor/azure-monitor-opentelemetry-exporter/tests/test_base_exporter.py

@@ -305,6 +305,28 @@ def test_transmit_from_storage_lease_failure(self):
         blob_mock.lease.assert_called_once()
         blob_mock.delete.assert_not_called()
 
+    def test_transmit_from_storage_blob_get_returns_none(self):
+        """Test that when blob.get() returns None, it's handled properly without TypeError."""
+        exporter = BaseExporter()
+        exporter.storage = mock.Mock()
+        blob_mock = mock.Mock()
+        blob_mock.lease.return_value = True
+        
+        blob_mock.get.return_value = None
+        exporter.storage.gets.return_value = [blob_mock]
+        transmit_mock = mock.Mock()
+        exporter._transmit = transmit_mock
+        
+        # This should not raise a TypeError
+        exporter._transmit_from_storage()
+        
+        # Verify that the blob was leased and deleted (since data was None)
+        exporter.storage.gets.assert_called_once()
+        blob_mock.lease.assert_called_once()
+        blob_mock.get.assert_called_once()
+        blob_mock.delete.assert_called_once()  # Corrupted blob should be deleted
+        transmit_mock.assert_not_called()  # No transmission should occur
+
 
     def test_format_storage_telemetry_item(self):
         time = datetime.now()