BenDcode
========
A python module for decoding bencoded data
Bencoding
---------
Bencoding is a meta data representation format fot the BitTorrent
Protocol (BTP). The Augmented BNF syntax for Bencoding is given below
::
dictionary = "d" 1*(string anytype) "e"
list = "l" 1*anytype "e"
integer = "i" signumber "e"
string = number ":" <number long sequence of any CHAR>
anytype = dictionary / list / integer / string
signumber = "-" number / number
number = 1*DIGIT
CHAR = %x00-FF
DIGIT = "0" / "1" / "2" / "3" / "4" /
"5" / "6" / "7" / "8" / "9"
**Source:** `BTP
RFC <http://jonas.nitro.dk/bittorrent/bittorrent-rfc.html>`__
Usage
-----
Decoding bencoded data is simple.
::
>>> import bendcode
>>> bendcode.decode('i123e')
123
>>> bendcode.decode('4:John')
'John'
>>> bendcode.decode('li234ei123ee')
[234, 123]
>>> bendcode.decode('d1:ai123e1:bi234ee')
{'a': 123, 'b': 234}
You can decode invidual types too !
::
>>> import bendcode
>>> bendcode.match_string('3:abc')
('abc', '')
>>> bendcode.match_int('i-123e')
(-123, '')
>>> bendcode.match_list('li123ee')
([123], '')
>>> bendcode.match_dict('d1:a1:bei123e')
({'a': 'b'}, 'i123e')
**Note:** The match\_\* series of functions return a tuple
``(first_possbile_match, remaining_unmatched_string)``
**Bendcode** can encode too
::
>>> import bendcode
>>> bendcode.encode(123)
'i123e'
>>> bendcode.encode('John')
'4:John'
>>> bendcode.encode([123, 'bro'])
'li123e3:broe'
>>> bendcode.encode({'hello': 123})
'd5:helloi123ee'
>>> bendcode.encode(None)
''
You decide whether to raise an exception or not for any functions
mentioned above by setting the ``fail_silently`` parameter to ``True``
or ``False``
::
>>> import bendcode
>>> bendcode.match_string('abc')
(None, 'abc')
>>> bendcode.match_string('abc', fail_silently=False)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "bendcode\bendcode.py", line 39, in match_string
raise MalformedBencodeError('Failed to match string in ' + str(raw))
bendcode.exceptions.MalformedBencodeError: Failed to match string in abc
Tests
-----
Run tests using the following code
::
>>> from bendcode import tests
>>> tests.run_tests()
..................................
----------------------------------------
Ran 34 tests in 0.015s
OK
Issues
------
If you find any bug, feel free to create an issue
`here <https://github.com/sanketh95/BenDcode/issues>`__.
License
-------
BenDcode uses GNU v2 License. Read the terms of the license
`here <https://github.com/sanketh95/BenDcode/blob/master/LICENSE.txt>`__.
