iso9075.py - Python codec for ISO-9075.
Copyright 2011 Jesús Torres <jmtorres@ull.es>


Description
-----------

This is a Python module that provides a codec for ISO-9075 although the standard
Python codec API. As this codec has been developed mainly for a web front-end
that speaks with Alfresco although SOAP (and the invalid characters in XML
NCNames must be ISO-9075 encoded[1]), the default codec registered with name
'iso9075' will only encode the characters invalid for a XML NCName[2].

However the module provides the function register() to add to the registry
a new codec (possibly with a different name) that selects the characters to
encode with a different rule. This is specified although a validation function
(returns True for valid characters and False for those that must be encoded)


Usage
-----

First we must import the module:

>>> import iso9075

Next we can encode some strings:

>>> "hello:world".encode('iso9075')
u'hello_x003a_world'

The codec converts the string to unicode internally so if it does not only
contains ascii characters, it is better to convert the string before.

>>> unicode("hellö:world", 'utf-8').encode('iso9075')
u'hell\xf6_x003a_world'

or

>>> u"hellö:world".encode('iso9075')
u'hell\xf6_x003a_world'

For decoding the same rules will apply, including what we said about the
conversion to unicode:

>>> u'hell\xf6_x003a_world'.decode('iso9075')
u'hell\xf6:world'


References
----------

[1] http://wiki.alfresco.com/wiki/Search#ISO_9075_encoding
[2] http://www.w3.org/TR/REC-xml/#NT-Name


-- Jesús Torres <jmtorres@ull.es>