mirror of
https://github.com/moparisthebest/SickRage
synced 2024-12-14 20:12:19 -05:00
77 lines
3.3 KiB
Python
77 lines
3.3 KiB
Python
"""A collection of modules for building different kinds of tree from
|
|
HTML documents.
|
|
|
|
To create a treebuilder for a new type of tree, you need to do
|
|
implement several things:
|
|
|
|
1) A set of classes for various types of elements: Document, Doctype,
|
|
Comment, Element. These must implement the interface of
|
|
_base.treebuilders.Node (although comment nodes have a different
|
|
signature for their constructor, see treebuilders.etree.Comment)
|
|
Textual content may also be implemented as another node type, or not, as
|
|
your tree implementation requires.
|
|
|
|
2) A treebuilder object (called TreeBuilder by convention) that
|
|
inherits from treebuilders._base.TreeBuilder. This has 4 required attributes:
|
|
documentClass - the class to use for the bottommost node of a document
|
|
elementClass - the class to use for HTML Elements
|
|
commentClass - the class to use for comments
|
|
doctypeClass - the class to use for doctypes
|
|
It also has one required method:
|
|
getDocument - Returns the root node of the complete document tree
|
|
|
|
3) If you wish to run the unit tests, you must also create a
|
|
testSerializer method on your treebuilder which accepts a node and
|
|
returns a string containing Node and its children serialized according
|
|
to the format used in the unittests
|
|
"""
|
|
|
|
from __future__ import absolute_import, division, unicode_literals
|
|
|
|
from ..utils import default_etree
|
|
|
|
treeBuilderCache = {}
|
|
|
|
|
|
def getTreeBuilder(treeType, implementation=None, **kwargs):
|
|
"""Get a TreeBuilder class for various types of tree with built-in support
|
|
|
|
treeType - the name of the tree type required (case-insensitive). Supported
|
|
values are:
|
|
|
|
"dom" - A generic builder for DOM implementations, defaulting to
|
|
a xml.dom.minidom based implementation.
|
|
"etree" - A generic builder for tree implementations exposing an
|
|
ElementTree-like interface, defaulting to
|
|
xml.etree.cElementTree if available and
|
|
xml.etree.ElementTree if not.
|
|
"lxml" - A etree-based builder for lxml.etree, handling
|
|
limitations of lxml's implementation.
|
|
|
|
implementation - (Currently applies to the "etree" and "dom" tree types). A
|
|
module implementing the tree type e.g.
|
|
xml.etree.ElementTree or xml.etree.cElementTree."""
|
|
|
|
treeType = treeType.lower()
|
|
if treeType not in treeBuilderCache:
|
|
if treeType == "dom":
|
|
from . import dom
|
|
# Come up with a sane default (pref. from the stdlib)
|
|
if implementation is None:
|
|
from xml.dom import minidom
|
|
implementation = minidom
|
|
# NEVER cache here, caching is done in the dom submodule
|
|
return dom.getDomModule(implementation, **kwargs).TreeBuilder
|
|
elif treeType == "lxml":
|
|
from . import etree_lxml
|
|
treeBuilderCache[treeType] = etree_lxml.TreeBuilder
|
|
elif treeType == "etree":
|
|
from . import etree
|
|
if implementation is None:
|
|
implementation = default_etree
|
|
# NEVER cache here, caching is done in the etree submodule
|
|
return etree.getETreeModule(implementation, **kwargs).TreeBuilder
|
|
else:
|
|
raise ValueError("""Unrecognised treebuilder "%s" """ % treeType)
|
|
return treeBuilderCache.get(treeType)
|