[Storage] Prepare hotfix release (#34608)

sdk/storage/azure-storage-blob/CHANGELOG.md

@@ -1,5 +1,11 @@
 # Release History
 
+## 12.19.1 (2024-03-04)
+
+### Bugs Fixed
+- Fixed an issue where under rare circumstances, full downloads of sparse Page Blobs could result in the
+downloaded content containing up to one "chunk" of extra `\x00` at the end due to an optimization error.
+
 ## 12.19.0 (2023-11-07)
 
 ### Features Added

sdk/storage/azure-storage-blob/assets.json

@@ -2,5 +2,5 @@
   "AssetsRepo": "Azure/azure-sdk-assets",
   "AssetsRepoPrefixPath": "python",
   "TagPrefix": "python/storage/azure-storage-blob",
-  "Tag": "python/storage/azure-storage-blob_12c8154ae2"
+  "Tag": "python/storage/azure-storage-blob_1b66da54e8"
 }

sdk/storage/azure-storage-blob/azure/storage/blob/_download.py

@@ -186,7 +186,8 @@ def _download_chunk(self, chunk_start, chunk_end):
         # No need to download the empty chunk from server if there's no data in the chunk to be downloaded.
         # Do optimize and create empty chunk locally if condition is met.
         if self._do_optimize(download_range[0], download_range[1]):
-            chunk_data = b"\x00" * self.chunk_size
+            data_size = download_range[1] - download_range[0] + 1
+            chunk_data = b"\x00" * data_size
         else:
             range_header, range_validation = validate_and_format_range_headers(
                 download_range[0],

sdk/storage/azure-storage-blob/azure/storage/blob/_version.py

@@ -4,4 +4,4 @@
 # license information.
 # --------------------------------------------------------------------------
 
-VERSION = "12.19.0"
+VERSION = "12.19.1"

sdk/storage/azure-storage-blob/azure/storage/blob/aio/_download_async.py

@@ -95,7 +95,8 @@ async def _download_chunk(self, chunk_start, chunk_end):
         # No need to download the empty chunk from server if there's no data in the chunk to be downloaded.
         # Do optimize and create empty chunk locally if condition is met.
         if self._do_optimize(download_range[0], download_range[1]):
-            chunk_data = b"\x00" * self.chunk_size
+            data_size = download_range[1] - download_range[0] + 1
+            chunk_data = b"\x00" * data_size
         else:
             range_header, range_validation = validate_and_format_range_headers(
                 download_range[0],

sdk/storage/azure-storage-blob/tests/test_page_blob.py

@@ -2269,6 +2269,45 @@ def test_download_sparse_page_blob_parallel(self, **kwargs):
 
         content = blob_client.download_blob(max_concurrency=3).readall()
 
+    @BlobPreparer()
+    @recorded_by_proxy
+    def test_download_sparse_page_blob_uneven_chunks(self, **kwargs):
+        storage_account_name = kwargs.pop("storage_account_name")
+        storage_account_key = kwargs.pop("storage_account_key")
+
+        # Arrange
+        bsc = BlobServiceClient(self.account_url(storage_account_name, "blob"), credential=storage_account_key)
+        self._setup(bsc)
+
+        # Choose an initial size, chunk size, and blob size, so the last chunk spills over end of blob
+        self.config.max_single_get_size = 4 * 1024
+        self.config.max_chunk_get_size = 4 * 1024
+        sparse_page_blob_size = 10 * 1024
+
+        blob_client = self._get_blob_reference(bsc)
+        blob_client.create_page_blob(sparse_page_blob_size)
+
+        data = b'12345678' * 128  # 1024 bytes
+        range_start = 2 * 1024 + 512
+        blob_client.upload_page(data, offset=range_start, length=len(data))
+
+        # Act
+        content = blob_client.download_blob().readall()
+
+        # Assert
+        assert sparse_page_blob_size == len(content)
+        start = end = 0
+        for r in blob_client.list_page_ranges():
+            if not r.cleared:
+                start = r.start
+                end = r.end
+
+        assert data == content[start: end + 1]
+        for byte in content[:start - 1]:
+            assert byte == 0
+        for byte in content[end + 1:]:
+            assert byte == 0
+
     @BlobPreparer()
     @recorded_by_proxy
     def test_upload_progress_chunked_non_parallel(self, **kwargs):

sdk/storage/azure-storage-blob/tests/test_page_blob_async.py

@@ -2238,6 +2238,45 @@ async def test_download_sparse_page_blob(self, storage_account_name, storage_acc
             except:
                 assert byte == 0
 
+    @BlobPreparer()
+    @recorded_by_proxy_async
+    async def test_download_sparse_page_blob_uneven_chunks(self, **kwargs):
+        storage_account_name = kwargs.pop("storage_account_name")
+        storage_account_key = kwargs.pop("storage_account_key")
+
+        # Arrange
+        bsc = BlobServiceClient(self.account_url(storage_account_name, "blob"), credential=storage_account_key)
+        await self._setup(bsc)
+
+        # Choose an initial size, chunk size, and blob size, so the last chunk spills over end of blob
+        self.config.max_single_get_size = 4 * 1024
+        self.config.max_chunk_get_size = 4 * 1024
+        sparse_page_blob_size = 10 * 1024
+
+        blob_client = self._get_blob_reference(bsc)
+        await blob_client.create_page_blob(sparse_page_blob_size)
+
+        data = b'12345678' * 128  # 1024 bytes
+        range_start = 2 * 1024 + 512
+        await blob_client.upload_page(data, offset=range_start, length=len(data))
+
+        # Act
+        content = await (await blob_client.download_blob()).readall()
+
+        # Assert
+        assert sparse_page_blob_size == len(content)
+        start = end = 0
+        async for r in blob_client.list_page_ranges():
+            if not r.cleared:
+                start = r.start
+                end = r.end
+
+        assert data == content[start: end + 1]
+        for byte in content[:start - 1]:
+            assert byte == 0
+        for byte in content[end + 1:]:
+            assert byte == 0
+
     @BlobPreparer()
     @recorded_by_proxy_async
     async def test_upload_progress_chunked_non_parallel(self, **kwargs):