JinmingHu (Jinming-Hu) · Oct 6, 2026 · Oct 6, 2026 · Oct 6, 2026 · Oct 6, 2026 · Oct 6, 2026
@@ -98,6 +98,7 @@
     "cgmanifest",
     "Chelnokov",
     "chewi",
+    "chinacloudapi",
     "Chukwu",
     "cmake",
     "CMOCKA",
@@ -291,6 +292,7 @@
     "unskipped",
     "UPNs",
     "usgov",
+    "usgovcloudapi",
     "usgoviowa",
     "usgovvirginia",
     "vcpkg",
@@ -315,6 +317,7 @@
     "Xclang",
     "xcode",
     "xcodebuild",
+    "xfiles",
     "XSMB",
     "zulu"
   ],

@@ -86,7 +86,7 @@ jobs:
         image: $(WINDOWSVMIMAGE)
         os: windows
       variables:
-        apiviewParserVersion: "20240927.5"
+        apiviewParserVersion: "20261009.3"
         VCPKG_DEFAULT_TRIPLET: 'x64-windows-static'
         Package.EnableSBOMSigning: true
       steps:
@@ -334,6 +334,8 @@ jobs:
             - template: /eng/common/pipelines/templates/steps/detect-api-changes.yml
               parameters:
                 ArtifactPath: $(Build.ArtifactStagingDirectory)\packages
+                # Test-only: keep JSON artifacts without submitting revisions to production APIView.
+                Condition: false
 
         - template: /eng/common/pipelines/templates/steps/publish-1es-artifact.yml
           parameters:

@@ -2,5 +2,5 @@
   "AssetsRepo": "Azure/azure-sdk-assets",
   "AssetsRepoPrefixPath": "cpp",
   "TagPrefix": "cpp/storage",
-  "Tag": "cpp/storage_6016ecf9a6"
+  "Tag": "cpp/storage_01f138ad9c"
 }
@@ -4,14 +4,28 @@
 
 ### Features Added
 
-### Breaking Changes
+- Added support for persisted session authentication for eligible blob download requests.
+- Added `BlobClient::GetLayout` and related options and response types for retrieving locality
+  endpoints, byte ranges, and blob properties. Ranges are exposed directly through
+  `Models::BlobLayoutInfo::Ranges` as a vector of `Models::BlobLayoutRange`.
+- Added `DownloadBlobOptions::LayoutEndpoint` for one-shot download routing and
+  `DownloadBlobToOptions::LayoutAwareRouting` (`Auto`, `Disabled`, `Enabled`; default `Disabled`) for
+  managed downloads.
+- Added `Models::DownloadHint` and `Models::DownloadBlobDetails::DownloadHint`.
 
 ### Bugs Fixed
 
 - Fixed CMake dependency resolution when FlatCC provides only a shared runtime library.
 
 ### Other Changes
 
+- Changed the default response format for `ListBlobs` and `ListBlobsByHierarchy` from XML to
+  Apache Arrow. Set `ListBlobsOptions::ResponseFormat` to `StorageResponseFormat::Xml` to continue
+  requesting XML responses.
+- Changed the default initial transfer size for partitioned uploads and downloads from 256 MiB to
+  4 MiB, matching the default subsequent chunk size. Explicitly configured
+  `InitialChunkSize` and `SingleUploadThreshold` values are still respected.
+
 ## 12.19.0 (2026-09-29)
 
 ### Features Added

@@ -75,7 +75,13 @@ set(
     src/page_blob_client.cpp
     src/private/avro_parser.cpp
     src/private/avro_parser.hpp
+    src/private/data_locality.cpp
+    src/private/data_locality.hpp
     src/private/package_version.hpp
+    src/private/session_authentication_policy.cpp
+    src/private/session_authentication_policy.hpp
+    src/private/token_credential_session_provider.cpp
+    src/private/token_credential_session_provider.hpp
     src/rest_client.cpp
 )
 

@@ -425,6 +425,17 @@ namespace Azure { namespace Storage { namespace Blobs {
         const GetAccountInfoOptions& options = GetAccountInfoOptions(),
         const Azure::Core::Context& context = Azure::Core::Context()) const;
 
+    /**
+     * @brief Gets the data locality layout for this blob.
+     *
+     * @param options Optional parameters to execute this function.
+     * @param context Context for cancelling long running operations.
+     * @return A paged response containing the blob's data locality layout.
+     */
+    BlobLayoutPagedResponse GetLayout(
+        const GetBlobLayoutOptions& options = GetBlobLayoutOptions(),
+        const Azure::Core::Context& context = Azure::Core::Context()) const;
+
   protected:
     /** @brief Blob Url */
     Azure::Core::Url m_blobUrl;

@@ -153,6 +153,14 @@ namespace Azure { namespace Storage { namespace Blobs {
      * @brief Marks the specified container for deletion. The container and any blobs
      * contained within it are later deleted during garbage collection.
      *
+     * @remark When a container is deleted, a container with the same name cannot be created for at
+     * least 30 seconds. The container might not be available for more than 30 seconds if the
+     * service is still processing the request. While the container is being deleted, attempts to
+     * create a container with the same name fail with status code 409 (Conflict). Operations on
+     * blobs within the container, including reads and writes, may continue to succeed for up to 30
+     * seconds after the delete request is accepted. After this period, all operations on the
+     * container and its blobs fail with status code 404 (Not Found).
+     *
      * @param options Optional parameters to execute this function.
      * @param context Context for cancelling long running operations.
      * @return A DeleteBlobContainerResult if successful.
@@ -165,6 +173,14 @@ namespace Azure { namespace Storage { namespace Blobs {
      * @brief Marks the specified container for deletion if it exists. The container and any blobs
      * contained within it are later deleted during garbage collection.
      *
+     * @remark When a container is deleted, a container with the same name cannot be created for at
+     * least 30 seconds. The container might not be available for more than 30 seconds if the
+     * service is still processing the request. While the container is being deleted, attempts to
+     * create a container with the same name fail with status code 409 (Conflict). Operations on
+     * blobs within the container, including reads and writes, may continue to succeed for up to 30
+     * seconds after the delete request is accepted. After this period, all operations on the
+     * container and its blobs fail with status code 404 (Not Found).
+     *
      * @param options Optional parameters to execute this function.
      * @param context Context for cancelling long running operations.
      * @return A DeleteBlobContainerResult if the container exists.

@@ -5,6 +5,9 @@
 
 #include "azure/storage/blobs/rest_client.hpp"
 
+#include <azure/core/credentials/credentials.hpp>
+#include <azure/core/datetime.hpp>
+#include <azure/core/http/http.hpp>
 #include <azure/core/internal/client_options.hpp>
 #include <azure/core/internal/extendable_enumeration.hpp>
 #include <azure/core/match_conditions.hpp>
@@ -23,6 +26,90 @@
 
 namespace Azure { namespace Storage { namespace Blobs {
 
+  class ContainerSessionProvider;
+  class SessionProvider;
+
+  namespace _detail {
+    class SessionAuthenticationPolicy;
+    class TokenCredentialSessionProvider;
+  } // namespace _detail
+
+  /**
+   * @brief Specifies how persisted session authentication is used.
+   */
+  enum class SessionMode
+  {
+    /**
+     * @brief Lets the SDK determine when to use sessions.
+     *
+     * @note Currently behaves the same as #Disabled.
+     */
+    Auto,
+
+    /**
+     * @brief Disables session authentication.
+     */
+    Disabled,
+
+    /**
+     * @brief Prefers session authentication for eligible requests.
+     *
+     * @note The client can fall back to bearer authentication while acquiring a session, when
+     * session creation is temporarily unavailable, or when the service rejects a session.
+     */
+    Enabled,
+  };
+
+  /**
+   * @brief Configures persisted session authentication.
+   */
+  struct SessionOptions final
+  {
+    /**
+     * @brief The session authentication mode.
+     *
+     * In Auto mode, clients currently use bearer authentication.
+     */
+    SessionMode Mode = SessionMode::Auto;
+
+    /**
+     * @brief Account name used when signing requests. Required when it cannot be inferred from URL.
+     *
+     * For custom endpoints, both AccountName and Provider must be specified.
+     */
+    std::string AccountName;
+
+    /**
+     * @brief Optional provider whose session cache can be shared by multiple clients.
+     *
+     * When unset, each independently constructed client creates its own provider. Clients derived
+     * from that client share its provider and cache. For custom endpoints, both Provider and
+     * AccountName must be specified.
+     */
+    std::shared_ptr<SessionProvider> Provider;
+  };
+
+  /**
+   * @brief Determines whether locality-aware routing is used for managed downloads.
+   */
+  enum class LayoutAwareRouting
+  {
+    /**
+     * @brief The client library determines whether locality-aware routing is enabled.
+     */
+    Auto,
+
+    /**
+     * @brief Locality-aware routing is disabled.
+     */
+    Disabled,
+
+    /**
+     * @brief Locality-aware routing is enabled.
+     */
+    Enabled,
+  };
+
   /**
    * @brief Audiences available for blob service
    *
@@ -287,6 +374,50 @@ namespace Azure { namespace Storage { namespace Blobs {
      * @brief Optional. Configures whether to do content validation for blob downloads.
      */
     Azure::Nullable<TransferValidationOptions> DownloadValidationOptions;
+
+    /**
+     * @brief Configures persisted session authentication.
+     */
+    Blobs::SessionOptions Session;
+  };
+
+  /**
+   * @brief Base type for providers that own and cache persisted sessions.
+   *
+   * Session providers can be shared by multiple clients through #SessionOptions::Provider.
+   * Use #ContainerSessionProvider for TokenCredential-based session authentication.
+   */
+  class SessionProvider {
+  public:
+    virtual ~SessionProvider();
+
+  private:
+    friend class ContainerSessionProvider;
+    friend class _detail::SessionAuthenticationPolicy;
+
+    SessionProvider();
+
+    std::shared_ptr<_detail::TokenCredentialSessionProvider> m_provider;
+  };
+
+  /**
+   * @brief Creates and caches container-scoped sessions using a TokenCredential.
+   */
+  class ContainerSessionProvider final : public SessionProvider {
+  public:
+    /**
+     * @brief Creates a provider backed by a TokenCredential.
+     *
+     * @param serviceUrl The Blob service URL.
+     * @param credential The credential used to create sessions.
+     * @param options Client options used by Create Session requests.
+     */
+    ContainerSessionProvider(
+        const std::string& serviceUrl,
+        std::shared_ptr<const Azure::Core::Credentials::TokenCredential> credential,
+        const BlobClientOptions& options);
+
+    ~ContainerSessionProvider() override;
   };
 
   /**
@@ -478,7 +609,7 @@ namespace Azure { namespace Storage { namespace Blobs {
   enum class StorageResponseFormat
   {
     /**
-     * @brief Let the service choose the response format (default).
+     * @brief Use the default response format, which is currently Apache Arrow.
      */
     Auto,
     /**
@@ -801,6 +932,14 @@ namespace Azure { namespace Storage { namespace Blobs {
      * @brief Optional. Configures whether to do content validation for blob downloads.
      */
     Azure::Nullable<TransferValidationOptions> ValidationOptions;
+
+    /**
+     * @brief Optional. The layout endpoint to use for this download.
+     *
+     * When set, the request is sent to this endpoint while preserving the client endpoint in the
+     * Host header.
+     */
+    std::string LayoutEndpoint;
   };
 
   /**
@@ -823,7 +962,7 @@ namespace Azure { namespace Storage { namespace Blobs {
        * downloaded in a single request. Blobs larger than this limit will continue being downloaded
        * in chunks of size ChunkSize.
        */
-      int64_t InitialChunkSize = 256 * 1024 * 1024;
+      int64_t InitialChunkSize = 4 * 1024 * 1024;
 
       /**
        * @brief The maximum number of bytes in a single request.
@@ -840,6 +979,12 @@ namespace Azure { namespace Storage { namespace Blobs {
      * @brief Optional. Configures whether to do content validation for blob downloads.
      */
     Azure::Nullable<TransferValidationOptions> ValidationOptions;
+
+    /**
+     * @brief Determines whether locality-aware routing is used for the parallel range requests.
+     * Disabled by default.
+     */
+    Blobs::LayoutAwareRouting LayoutAwareRouting = Blobs::LayoutAwareRouting::Disabled;
   };
 
   /**
@@ -1069,7 +1214,7 @@ namespace Azure { namespace Storage { namespace Blobs {
        * @brief Blob smaller than this will be uploaded with a single upload operation. This value
        * cannot be larger than 5000 MiB.
        */
-      int64_t SingleUploadThreshold = 256 * 1024 * 1024;
+      int64_t SingleUploadThreshold = 4 * 1024 * 1024;
 
       /**
        * @brief The maximum number of bytes in a single request. This value cannot be larger than
@@ -1812,6 +1957,27 @@ namespace Azure { namespace Storage { namespace Blobs {
   {
   };
 
+  /**
+   * @brief Optional parameters for #Azure::Storage::Blobs::BlobClient::GetLayout.
+   */
+  struct GetBlobLayoutOptions final
+  {
+    /**
+     * @brief The range of bytes for which to retrieve the layout.
+     */
+    Azure::Nullable<Core::Http::HttpRange> Range;
+
+    /**
+     * @brief The continuation token for retrieving the next page.
+     */
+    Azure::Nullable<std::string> ContinuationToken;
+
+    /**
+     * @brief Access conditions for the operation.
+     */
+    BlobAccessConditions AccessConditions;
+  };
+
   namespace _detail {
     inline std::string TagsToString(const std::map<std::string, std::string>& tags)
     {