filelike 0.4.1

filelike is a Python library for creating and handling file-like objects.<br /><br />This module takes care of the groundwork for implementing and manipulating objects that provide a rich file-like interface, including reading, writing, seeking and iteration. It also provides a number of useful classes built on top of this functionality.<br /><br />The main class is FileLikeBase, which implements the entire file-like interface on top of primitive _read(), _write(), _seek() and _tell() methods. Subclasses may implement any or all of these methods to obtain the related higher-level file behaviors.<br /><br />It also provides some nifty file-handling functions:<br /><br />* open: mirrors the standard open() function but is much cleverer;<br /><br /> URLs are automatically fetched, .bz2 files are transparently decompressed, and so-on.<br /><br />* join: concatenate multiple file-like objects together so that they<br /><br /> act like a single file.<br /><br />* slice: access a section of a file-like object as if it were an independent file.<br /><br />The "wrappers" subpackage contains a collection of useful classes built on top of this framework. These include:<br /><br />* Translate: pass file contents through an arbitrary translation<br /><br /> function (e.g. compression, encryption, ...)<br /><br />* Decrypt: on-the-fly reading and writing to an encrypted file<br /><br /> (using PEP272 cipher API)<br /><br />* UnBZip2: on-the-fly decompression of bzip'd files<br /><br />(like the standard library's bz2 module, but accepts any file-like object)<br /><br />As an example of the type of thing this module is designed to achieve, here's how the Decrypt wrapper can be used to transparently access an encrypted file:<br /><br /># Create the decryption key from Crypto.Cipher import DES cipher = DES.new('abcdefgh',DES.MODE_ECB) # Open the encrypted file from filelike.wrappers import Decrypt f = Decrypt(file("some_encrypted_file.bin","r"),cipher)<br /><br />The object in 'f' now behaves as a file-like object, transparently decrypting the file on-the-fly as it is read.<br /><br />The "pipeline" subpackage contains facilities for composing these wrappers in the form of a unix pipeline. In the following example, 'f' will read the first five lines of an encrypted file:<br /><br />from filelike.pipeline import Decrypt, Head f = file("some_encrypted_file.bin") > Decrypt(cipher) | Head(lines=5)<br /><br />Finally, two utility functions are provided for when code expects to deal with file-like objects:<br /><br />* is_filelike(obj): checks that an object is file-like<br />* to_filelike(obj): wraps a variety of objects in a file-like interface

Requirements:	No special requirements
Platforms:	*nix, Linux
Keyword:	039f039,  Access,  Built,  Classes,  Decrypt,  Encrypted,  Filelike,  Function,  Functions,  Import,  Interface,  Methods,  Module,  Object,  Objects,  Onthefly,  Standard,  Transparently
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