######################################################################
#
# File: b2sdk/upload_source.py
#
# Copyright 2019 Backblaze Inc. All Rights Reserved.
#
# License https://www.backblaze.com/using_b2_code.html
#
######################################################################
import hashlib
import os
from abc import (ABCMeta, abstractmethod)
import six
from .exception import InvalidUploadSource
from .utils import (BytesIoContextManager, hex_sha1_of_stream)
[docs]@six.add_metaclass(ABCMeta)
class AbstractUploadSource(object):
"""
The source of data for uploading to b2.
"""
[docs] @abstractmethod
def get_content_length(self):
"""
Return the number of bytes of data in the file.
"""
[docs] @abstractmethod
def get_content_sha1(self):
"""
Return a 40-character string containing the hex SHA1 checksum of the data in the file.
"""
[docs] @abstractmethod
def open(self):
"""
Return a binary file-like object from which the
data can be read.
:return:
"""
[docs]class UploadSourceBytes(AbstractUploadSource):
[docs] def __init__(self, data_bytes):
self.data_bytes = data_bytes
[docs] def get_content_length(self):
return len(self.data_bytes)
[docs] def get_content_sha1(self):
return hashlib.sha1(self.data_bytes).hexdigest()
[docs] def open(self):
return BytesIoContextManager(self.data_bytes)
[docs]class UploadSourceLocalFile(AbstractUploadSource):
[docs] def __init__(self, local_path, content_sha1=None):
self.local_path = local_path
if not os.path.isfile(local_path):
raise InvalidUploadSource(local_path)
self.content_length = os.path.getsize(local_path)
self.content_sha1 = content_sha1
[docs] def get_content_length(self):
return self.content_length
[docs] def get_content_sha1(self):
if self.content_sha1 is None:
self.content_sha1 = self._hex_sha1_of_file(self.local_path)
return self.content_sha1
[docs] def open(self):
return open(self.local_path, 'rb')
def _hex_sha1_of_file(self, local_path):
with open(local_path, 'rb') as f:
return hex_sha1_of_stream(f, self.content_length)