ai-content-maker/.venv/Lib/site-packages/smart_open/azure.py

528 lines
17 KiB
Python

# -*- coding: utf-8 -*-
#
# Copyright (C) 2020 Radim Rehurek <radim@rare-technologies.com>
# Copyright (C) 2020 Nicolas Mitchell <ncls.mitchell@gmail.com>
#
# This code is distributed under the terms and conditions
# from the MIT License (MIT).
#
"""Implements file-like objects for reading and writing to/from Azure Blob Storage."""
import base64
import io
import logging
import smart_open.bytebuffer
import smart_open.constants
try:
import azure.storage.blob
import azure.core.exceptions
except ImportError:
MISSING_DEPS = True
logger = logging.getLogger(__name__)
_BINARY_TYPES = (bytes, bytearray, memoryview)
"""Allowed binary buffer types for writing to the underlying Azure Blob Storage stream"""
SCHEME = "azure"
"""Supported scheme for Azure Blob Storage in smart_open endpoint URL"""
_DEFAULT_MIN_PART_SIZE = 64 * 1024**2
"""Default minimum part size for Azure Cloud Storage multipart uploads is 64MB"""
DEFAULT_BUFFER_SIZE = 4 * 1024**2
"""Default buffer size for working with Azure Blob Storage is 256MB
https://docs.microsoft.com/en-us/rest/api/storageservices/understanding-block-blobs--append-blobs--and-page-blobs
"""
DEFAULT_MAX_CONCURRENCY = 1
"""Default number of parallel connections with which to download."""
def parse_uri(uri_as_string):
sr = smart_open.utils.safe_urlsplit(uri_as_string)
assert sr.scheme == SCHEME
first = sr.netloc
second = sr.path.lstrip('/')
# https://docs.microsoft.com/en-us/rest/api/storageservices/working-with-the-root-container
if not second:
container_id = '$root'
blob_id = first
else:
container_id = first
blob_id = second
return dict(scheme=SCHEME, container_id=container_id, blob_id=blob_id)
def open_uri(uri, mode, transport_params):
parsed_uri = parse_uri(uri)
kwargs = smart_open.utils.check_kwargs(open, transport_params)
return open(parsed_uri['container_id'], parsed_uri['blob_id'], mode, **kwargs)
def open(
container_id,
blob_id,
mode,
client=None, # type: Union[azure.storage.blob.BlobServiceClient, azure.storage.blob.ContainerClient, azure.storage.blob.BlobClient] # noqa
blob_kwargs=None,
buffer_size=DEFAULT_BUFFER_SIZE,
min_part_size=_DEFAULT_MIN_PART_SIZE,
max_concurrency=DEFAULT_MAX_CONCURRENCY,
):
"""Open an Azure Blob Storage blob for reading or writing.
Parameters
----------
container_id: str
The name of the container this object resides in.
blob_id: str
The name of the blob within the bucket.
mode: str
The mode for opening the object. Must be either "rb" or "wb".
client: azure.storage.blob.BlobServiceClient, ContainerClient, or BlobClient
The Azure Blob Storage client to use when working with azure-storage-blob.
blob_kwargs: dict, optional
Additional parameters to pass to `BlobClient.commit_block_list`.
For writing only.
buffer_size: int, optional
The buffer size to use when performing I/O. For reading only.
min_part_size: int, optional
The minimum part size for multipart uploads. For writing only.
max_concurrency: int, optional
The number of parallel connections with which to download. For reading only.
"""
if not client:
raise ValueError('you must specify the client to connect to Azure')
if mode == smart_open.constants.READ_BINARY:
return Reader(
container_id,
blob_id,
client,
buffer_size=buffer_size,
line_terminator=smart_open.constants.BINARY_NEWLINE,
max_concurrency=max_concurrency,
)
elif mode == smart_open.constants.WRITE_BINARY:
return Writer(
container_id,
blob_id,
client,
blob_kwargs=blob_kwargs,
min_part_size=min_part_size
)
else:
raise NotImplementedError('Azure Blob Storage support for mode %r not implemented' % mode)
def _get_blob_client(client, container, blob):
# type: (Union[azure.storage.blob.BlobServiceClient, azure.storage.blob.ContainerClient, azure.storage.blob.BlobClient], str, str) -> azure.storage.blob.BlobClient # noqa
"""
Return an Azure BlobClient starting with any of BlobServiceClient,
ContainerClient, or BlobClient plus container name and blob name.
"""
if hasattr(client, "get_container_client"):
client = client.get_container_client(container)
if hasattr(client, "container_name") and client.container_name != container:
raise ValueError(
"Client for %r doesn't match "
"container %r" % (client.container_name, container)
)
if hasattr(client, "get_blob_client"):
client = client.get_blob_client(blob)
return client
class _RawReader(object):
"""Read an Azure Blob Storage file."""
def __init__(self, blob, size, concurrency):
# type: (azure.storage.blob.BlobClient, int, int) -> None
self._blob = blob
self._size = size
self._position = 0
self._concurrency = concurrency
def seek(self, position):
"""Seek to the specified position (byte offset) in the Azure Blob Storage blob.
:param int position: The byte offset from the beginning of the blob.
Returns the position after seeking.
"""
self._position = position
return self._position
def read(self, size=-1):
if self._position >= self._size:
return b''
binary = self._download_blob_chunk(size)
self._position += len(binary)
return binary
def _download_blob_chunk(self, size):
if self._size == self._position:
#
# When reading, we can't seek to the first byte of an empty file.
# Similarly, we can't seek past the last byte. Do nothing here.
#
return b''
elif size == -1:
stream = self._blob.download_blob(offset=self._position, max_concurrency=self._concurrency)
else:
stream = self._blob.download_blob(
offset=self._position, max_concurrency=self._concurrency, length=size)
logging.debug('reading with a max concurrency of %d', self._concurrency)
if isinstance(stream, azure.storage.blob.StorageStreamDownloader):
binary = stream.readall()
else:
binary = stream.read()
return binary
class Reader(io.BufferedIOBase):
"""Reads bytes from Azure Blob Storage.
Implements the io.BufferedIOBase interface of the standard library.
:raises azure.core.exceptions.ResourceNotFoundError: Raised when the blob to read from does not exist.
"""
def __init__(
self,
container,
blob,
client, # type: Union[azure.storage.blob.BlobServiceClient, azure.storage.blob.ContainerClient, azure.storage.blob.BlobClient] # noqa
buffer_size=DEFAULT_BUFFER_SIZE,
line_terminator=smart_open.constants.BINARY_NEWLINE,
max_concurrency=DEFAULT_MAX_CONCURRENCY,
):
self._container_name = container
self._blob = _get_blob_client(client, container, blob)
# type: azure.storage.blob.BlobClient
if self._blob is None:
raise azure.core.exceptions.ResourceNotFoundError(
'blob %s not found in %s' % (blob, container)
)
try:
self._size = self._blob.get_blob_properties()['size']
except KeyError:
self._size = 0
self._raw_reader = _RawReader(self._blob, self._size, max_concurrency)
self._position = 0
self._current_part = smart_open.bytebuffer.ByteBuffer(buffer_size)
self._line_terminator = line_terminator
#
# This member is part of the io.BufferedIOBase interface.
#
self.raw = None
#
# Override some methods from io.IOBase.
#
def close(self):
"""Flush and close this stream."""
logger.debug("close: called")
self._blob = None
self._raw_reader = None
def readable(self):
"""Return True if the stream can be read from."""
return True
def seekable(self):
"""If False, seek(), tell() and truncate() will raise IOError.
We offer only seek support, and no truncate support."""
return True
#
# io.BufferedIOBase methods.
#
def detach(self):
"""Unsupported."""
raise io.UnsupportedOperation
def seek(self, offset, whence=smart_open.constants.WHENCE_START):
"""Seek to the specified position.
:param int offset: The offset in bytes.
:param int whence: Where the offset is from.
Returns the position after seeking."""
logger.debug('seeking to offset: %r whence: %r', offset, whence)
if whence not in smart_open.constants.WHENCE_CHOICES:
raise ValueError('invalid whence %i, expected one of %r' % (whence,
smart_open.constants.WHENCE_CHOICES))
if whence == smart_open.constants.WHENCE_START:
new_position = offset
elif whence == smart_open.constants.WHENCE_CURRENT:
new_position = self._position + offset
else:
new_position = self._size + offset
self._position = new_position
self._raw_reader.seek(new_position)
logger.debug('current_pos: %r', self._position)
self._current_part.empty()
return self._position
def tell(self):
"""Return the current position within the file."""
return self._position
def truncate(self, size=None):
"""Unsupported."""
raise io.UnsupportedOperation
def read(self, size=-1):
"""Read up to size bytes from the object and return them."""
if size == 0:
return b''
elif size < 0:
self._position = self._size
return self._read_from_buffer() + self._raw_reader.read()
#
# Return unused data first
#
if len(self._current_part) >= size:
return self._read_from_buffer(size)
if self._position == self._size:
return self._read_from_buffer()
self._fill_buffer(size)
return self._read_from_buffer(size)
def read1(self, size=-1):
"""This is the same as read()."""
return self.read(size=size)
def readinto(self, b):
"""Read up to len(b) bytes into b, and return the number of bytes read."""
data = self.read(len(b))
if not data:
return 0
b[:len(data)] = data
return len(data)
def readline(self, limit=-1):
"""Read up to and including the next newline. Returns the bytes read."""
if limit != -1:
raise NotImplementedError('limits other than -1 not implemented yet')
the_line = io.BytesIO()
while not (self._position == self._size and len(self._current_part) == 0):
#
# In the worst case, we're reading the unread part of self._current_part
# twice here, once in the if condition and once when calling index.
#
# This is sub-optimal, but better than the alternative: wrapping
# .index in a try..except, because that is slower.
#
remaining_buffer = self._current_part.peek()
if self._line_terminator in remaining_buffer:
next_newline = remaining_buffer.index(self._line_terminator)
the_line.write(self._read_from_buffer(next_newline + 1))
break
else:
the_line.write(self._read_from_buffer())
self._fill_buffer()
return the_line.getvalue()
#
# Internal methods.
#
def _read_from_buffer(self, size=-1):
"""Remove at most size bytes from our buffer and return them."""
# logger.debug('reading %r bytes from %r byte-long buffer', size, len(self._current_part))
size = size if size >= 0 else len(self._current_part)
part = self._current_part.read(size)
self._position += len(part)
# logger.debug('part: %r', part)
return part
def _fill_buffer(self, size=-1):
size = max(size, self._current_part._chunk_size)
while len(self._current_part) < size and not self._position == self._size:
bytes_read = self._current_part.fill(self._raw_reader)
if bytes_read == 0:
logger.debug('reached EOF while filling buffer')
return True
def __enter__(self):
return self
def __exit__(self, exc_type, exc_val, exc_tb):
self.close()
def __str__(self):
return "(%s, %r, %r)" % (self.__class__.__name__,
self._container_name,
self._blob.blob_name)
def __repr__(self):
return "%s(container=%r, blob=%r)" % (
self.__class__.__name__, self._container_name, self._blob.blob_name,
)
class Writer(io.BufferedIOBase):
"""Writes bytes to Azure Blob Storage.
Implements the io.BufferedIOBase interface of the standard library."""
def __init__(
self,
container,
blob,
client, # type: Union[azure.storage.blob.BlobServiceClient, azure.storage.blob.ContainerClient, azure.storage.blob.BlobClient] # noqa
blob_kwargs=None,
min_part_size=_DEFAULT_MIN_PART_SIZE,
):
self._is_closed = False
self._container_name = container
self._blob = _get_blob_client(client, container, blob)
self._blob_kwargs = blob_kwargs or {}
# type: azure.storage.blob.BlobClient
self._min_part_size = min_part_size
self._total_size = 0
self._total_parts = 0
self._bytes_uploaded = 0
self._current_part = io.BytesIO()
self._block_list = []
#
# This member is part of the io.BufferedIOBase interface.
#
self.raw = None
def flush(self):
pass
#
# Override some methods from io.IOBase.
#
def close(self):
logger.debug("closing")
if not self.closed:
if self._current_part.tell() > 0:
self._upload_part()
self._blob.commit_block_list(self._block_list, **self._blob_kwargs)
self._block_list = []
self._is_closed = True
logger.debug("successfully closed")
@property
def closed(self):
return self._is_closed
def writable(self):
"""Return True if the stream supports writing."""
return True
def seekable(self):
"""If False, seek(), tell() and truncate() will raise IOError.
We offer only tell support, and no seek or truncate support."""
return True
def seek(self, offset, whence=smart_open.constants.WHENCE_START):
"""Unsupported."""
raise io.UnsupportedOperation
def truncate(self, size=None):
"""Unsupported."""
raise io.UnsupportedOperation
def tell(self):
"""Return the current stream position."""
return self._total_size
#
# io.BufferedIOBase methods.
#
def detach(self):
raise io.UnsupportedOperation("detach() not supported")
def write(self, b):
"""Write the given bytes (binary string) to the Azure Blob Storage file.
There's buffering happening under the covers, so this may not actually
do any HTTP transfer right away."""
if not isinstance(b, _BINARY_TYPES):
raise TypeError("input must be one of %r, got: %r" % (_BINARY_TYPES, type(b)))
self._current_part.write(b)
self._total_size += len(b)
if self._current_part.tell() >= self._min_part_size:
self._upload_part()
return len(b)
def _upload_part(self):
part_num = self._total_parts + 1
content_length = self._current_part.tell()
range_stop = self._bytes_uploaded + content_length - 1
""" # noqa: E501
block_id's must be base64 encoded, all the same length, and less than or equal to 64 bytes in size prior
to encoding.
https://docs.microsoft.com/en-us/python/api/azure-storage-blob/azure.storage.blob.blobclient?view=azure-python#stage-block-block-id--data--length-none----kwargs-
"""
zero_padded_part_num = str(part_num).zfill(64 // 2)
block_id = base64.b64encode(zero_padded_part_num.encode())
self._current_part.seek(0)
self._blob.stage_block(block_id, self._current_part.read(content_length))
self._block_list.append(azure.storage.blob.BlobBlock(block_id=block_id))
logger.info(
"uploading part #%i, %i bytes (total %.3fGB)",
part_num, content_length, range_stop / 1024.0 ** 3,
)
self._total_parts += 1
self._bytes_uploaded += content_length
self._current_part = io.BytesIO(self._current_part.read())
self._current_part.seek(0, io.SEEK_END)
def __enter__(self):
return self
def __exit__(self, exc_type, exc_val, exc_tb):
self.close()
def __str__(self):
return "(%s, %r, %r)" % (
self.__class__.__name__,
self._container_name,
self._blob.blob_name
)
def __repr__(self):
return "%s(container=%r, blob=%r, min_part_size=%r)" % (
self.__class__.__name__,
self._container_name,
self._blob.blob_name,
self._min_part_size
)