b2sdk._internal.transfer.inbound.downloader.abstract – Downloader base class

class b2sdk._internal.transfer.inbound.downloader.abstract.EmptyHasher(*args, **kwargs)

Bases: object

__init__(*args, **kwargs)

update(data)

digest()

hexdigest()

copy()

class b2sdk._internal.transfer.inbound.downloader.abstract.AbstractDownloader(thread_pool=None, force_chunk_size=None, min_chunk_size=None, max_chunk_size=None, align_factor=None, check_hash=True, **kwargs)

Bases: object

Abstract class for downloaders.

Variables:

• REQUIRES_SEEKING – if True, the downloader requires the ability to seek in the file object.

• SUPPORTS_DECODE_CONTENT – if True, the downloader supports decoded HTTP streams. In practice, this means that the downloader can handle HTTP responses which already have the content decoded per Content-Encoding and, more likely than not, of a different length than requested.

Parameters:

• thread_pool (Optional[ThreadPoolExecutor]) –

• force_chunk_size (Optional[int]) –

• min_chunk_size (Optional[int]) –

• max_chunk_size (Optional[int]) –

• align_factor (Optional[int]) –

• check_hash (bool) –

REQUIRES_SEEKING = True

SUPPORTS_DECODE_CONTENT = True

DEFAULT_THREAD_POOL_CLASS

alias of ThreadPoolExecutor

DEFAULT_ALIGN_FACTOR = 4096

__init__(thread_pool=None, force_chunk_size=None, min_chunk_size=None, max_chunk_size=None, align_factor=None, check_hash=True, **kwargs)

Parameters:

• thread_pool (Optional[ThreadPoolExecutor]) –

• force_chunk_size (Optional[int]) –

• min_chunk_size (Optional[int]) –

• max_chunk_size (Optional[int]) –

• align_factor (Optional[int]) –

• check_hash (bool) –

is_suitable(download_version, allow_seeking)

Analyze download_version (possibly against options passed earlier to constructor to find out whether the given download request should be handled by this downloader).

Parameters:

• download_version (DownloadVersion) –

• allow_seeking (bool) –

abstract download(file, response, download_version, session, encryption=None)

Download target to a file-like object.

Parameters:

• file (IOBase) – file-like object to write to

• response (Response) – requests.Response of b2_download_url_by_* endpoint with the target object

• download_version (DownloadVersion) – DownloadVersion of an object being downloaded

• session (B2Session) – B2Session to be used for downloading

• encryption (Optional[EncryptionSetting]) – optional Encryption setting

Return type:

tuple[int, str]

Returns:

(bytes_read, actual_sha1) please note bytes_read may be different from bytes written to a file object if decode_content=True