The freezer.utils.checksum Module¶

class freezer.utils.checksum.CheckSum(path, hasher_type='sha256', blocksize=1048576, exclude='', ignorelinks=False)¶

Bases: object

Checksum a file or directory with sha256 or md5 algorithms.

This is used by backup and restore jobs to check for backup consistency.

• parameters::

  param path:	the path to the file or directory to checksum
  type path:	string
  param hasher_type:
  	the hashing algorithm to use for checksum
  type hasher_type:
  	string
  param hasher:	hasher object for the specified hasher_type
  type hasher:	hashlib object
  param blocksize:
  	the max. size of block to read when hashing a file
  type blocksize:	integer
  param exclude:	pattern of files to exclude
  type exclude:	string
  param checksum:	final result for checksum computing
  type checksum:	string
  param real_checksum:
  	checksum without filename appended if unique file
  type real_checksum:
  	string
  param count:	number of files checksummed
  type count:	int

compare(checksum)¶

Compute the checksum for the object path and compare with the given checksum. :return: boolean

compute()¶

Compute the checksum for the given path. If a single file is provided, the result is its checksum concatenated with its name. If a directory is provided, the result is the checksum of the checksum concatenation for each file. :return: string

get_files_hashes_in_path()¶

Walk the files in path computing the checksum for each one and updates the concatenation checksum for the final result

get_hash(filepath)¶

Open filename and calculate its hash. Append the hash to the previous result and stores the checksum for this concatenation :param filepath: path to file :type filepath: string :return: string containing the hash of the given file

hashes = []¶

hashfile(afile)¶

Checksum a single file with the chosen algorithm. The file is read in chunks of self.blocksize. :return: string

hashstring(string)¶

Returns:	the hash for a given string

set_hasher(hasher_type)¶

Sets the hasher from hashlib according to the chosen hasher_type. Also sets the size of the expected output