repoze.xmliter 0.3

Wrapper for ``lxml`` trees which serializes to string upon iteration.

This package provides a wrapper for lxml trees which serializes to string on iteration, but otherwise makes the tree available in an attribute.

The primary for this is WSGI middleware which may avoid needless XML parsing and serialization.

Usage

It’s recommend to use the lazy decorator on your application method. This allows you to return an lxml tree object, which is then automatically turned into an XMLSerializer.

>>> from repoze.xmliter import lazy

>>> @lazy
... def application(environ, start_response)
...     return some_lxml_tree

You may provide a serializer function, which will be used when the XMLSerializer is eventually iterated over (i.e. when the response is rendered):

>>> @lazy(serializer=lxml.html.tostring)
... def application(environ, start_response)
...     return some_lxml_tree

Middleware can use isinstance to test if the result is an XML iterable:

>>> from repoze.xmliter.serializer import XMLSerializer
>>> isinstance(result, XMLSerializer)

In this case, the middleware can simply access the tree attribute of the result.

There are two convenience methods which can be used to parse a WSGI iterable of strings and build an XMLSerializer object, but avoids re-building the serializer if the input iterable is already an instance of XMLSerializer:

>>> from repoze.xmliter.utils import getXMLSerializer
>>> result = getXMLSerializer(result)

Or, if you are parsing HTML:

>>> from repoze.xmliter.utils import getHTMLSerializer
>>> result = getHTMLSerializer(result)

If result is not an XMLSerializer, it will be parsed using a feed parser, turned into an lxml tree, and wrapped up in an XMLSerializer, which is returned.

Changelog

0.3 - 2011-06-03

• Add doctype option to replace doctype on serialization. [Laurence]

0.2 - 2010-09-11

• Use document encoding by default. (This fixes test failure on Ubuntu 10.04.) [Laurence]

• Defer to xsl:output settings when serializing an XSLResultTree. [Laurence]

• Turn off pretty printing by default for HTML to avoid affecting rendering on the browser. [Laurence]

0.1 - 2010-04-21

• Initial release