Azure/azure-sdk-for-python azure-storage-file-datalake_12.27.0b1

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12.27.0b1 (2026-11-04)

Breaking Changes

• Custom transports that use legacy azure-core Request/Response types will no longer be supported and may now cause errors if used. Please ensure custom transports are utilizing types from azure.core.rest.
• Changed the default max_single_get_size from 32 MiB to 4 MiB. This means the initial download request will now be 4 MiB rather than 32 MiB which may result in more requests than previous versions depending on file size. This also means some file downloads may use parallel requests when they were not previously, if max_concurrency is set greater than 1. To restore the previous behavior, pass max_single_get_size = 32 * 1024 * 1024 when constructing the client.

Features Added

• Added support for service versions 2026-12-06 and 2027-03-07.
• Added opt-in client session-based authentication via the new use_session keyword argument. When enabled, eligible file read requests are authenticated with a short-lived, per-file-system session credential obtained from the service rather than the bearer token. Requires a TokenCredential. Sessions are managed by a session provider, which can be shared across clients via the session_provider keyword, and the account name used for signing can be set explicitly with session_account_name.

Bugs Fixed

• Fixed an issue where a SAS generated for a path containing a backslash (\) was invalid because the backslash was not normalized to a forward slash when building the signed resource.

Other Changes

• Content-Type for append_data has changed from application/json to octet-stream
• Migrated generated code to use the new TypeSpec generator.