268 lines
8.4 KiB
Python
268 lines
8.4 KiB
Python
# -*- test-case-name: twisted.web.test.test_domhelpers -*-
|
|
# Copyright (c) Twisted Matrix Laboratories.
|
|
# See LICENSE for details.
|
|
|
|
"""
|
|
A library for performing interesting tasks with DOM objects.
|
|
"""
|
|
|
|
import StringIO
|
|
|
|
from twisted.web import microdom
|
|
from twisted.web.microdom import getElementsByTagName, escape, unescape
|
|
|
|
|
|
class NodeLookupError(Exception):
|
|
pass
|
|
|
|
|
|
def substitute(request, node, subs):
|
|
"""
|
|
Look through the given node's children for strings, and
|
|
attempt to do string substitution with the given parameter.
|
|
"""
|
|
for child in node.childNodes:
|
|
if hasattr(child, 'nodeValue') and child.nodeValue:
|
|
child.replaceData(0, len(child.nodeValue), child.nodeValue % subs)
|
|
substitute(request, child, subs)
|
|
|
|
def _get(node, nodeId, nodeAttrs=('id','class','model','pattern')):
|
|
"""
|
|
(internal) Get a node with the specified C{nodeId} as any of the C{class},
|
|
C{id} or C{pattern} attributes.
|
|
"""
|
|
|
|
if hasattr(node, 'hasAttributes') and node.hasAttributes():
|
|
for nodeAttr in nodeAttrs:
|
|
if (str (node.getAttribute(nodeAttr)) == nodeId):
|
|
return node
|
|
if node.hasChildNodes():
|
|
if hasattr(node.childNodes, 'length'):
|
|
length = node.childNodes.length
|
|
else:
|
|
length = len(node.childNodes)
|
|
for childNum in range(length):
|
|
result = _get(node.childNodes[childNum], nodeId)
|
|
if result: return result
|
|
|
|
def get(node, nodeId):
|
|
"""
|
|
Get a node with the specified C{nodeId} as any of the C{class},
|
|
C{id} or C{pattern} attributes. If there is no such node, raise
|
|
L{NodeLookupError}.
|
|
"""
|
|
result = _get(node, nodeId)
|
|
if result: return result
|
|
raise NodeLookupError, nodeId
|
|
|
|
def getIfExists(node, nodeId):
|
|
"""
|
|
Get a node with the specified C{nodeId} as any of the C{class},
|
|
C{id} or C{pattern} attributes. If there is no such node, return
|
|
C{None}.
|
|
"""
|
|
return _get(node, nodeId)
|
|
|
|
def getAndClear(node, nodeId):
|
|
"""Get a node with the specified C{nodeId} as any of the C{class},
|
|
C{id} or C{pattern} attributes. If there is no such node, raise
|
|
L{NodeLookupError}. Remove all child nodes before returning.
|
|
"""
|
|
result = get(node, nodeId)
|
|
if result:
|
|
clearNode(result)
|
|
return result
|
|
|
|
def clearNode(node):
|
|
"""
|
|
Remove all children from the given node.
|
|
"""
|
|
node.childNodes[:] = []
|
|
|
|
def locateNodes(nodeList, key, value, noNesting=1):
|
|
"""
|
|
Find subnodes in the given node where the given attribute
|
|
has the given value.
|
|
"""
|
|
returnList = []
|
|
if not isinstance(nodeList, type([])):
|
|
return locateNodes(nodeList.childNodes, key, value, noNesting)
|
|
for childNode in nodeList:
|
|
if not hasattr(childNode, 'getAttribute'):
|
|
continue
|
|
if str(childNode.getAttribute(key)) == value:
|
|
returnList.append(childNode)
|
|
if noNesting:
|
|
continue
|
|
returnList.extend(locateNodes(childNode, key, value, noNesting))
|
|
return returnList
|
|
|
|
def superSetAttribute(node, key, value):
|
|
if not hasattr(node, 'setAttribute'): return
|
|
node.setAttribute(key, value)
|
|
if node.hasChildNodes():
|
|
for child in node.childNodes:
|
|
superSetAttribute(child, key, value)
|
|
|
|
def superPrependAttribute(node, key, value):
|
|
if not hasattr(node, 'setAttribute'): return
|
|
old = node.getAttribute(key)
|
|
if old:
|
|
node.setAttribute(key, value+'/'+old)
|
|
else:
|
|
node.setAttribute(key, value)
|
|
if node.hasChildNodes():
|
|
for child in node.childNodes:
|
|
superPrependAttribute(child, key, value)
|
|
|
|
def superAppendAttribute(node, key, value):
|
|
if not hasattr(node, 'setAttribute'): return
|
|
old = node.getAttribute(key)
|
|
if old:
|
|
node.setAttribute(key, old + '/' + value)
|
|
else:
|
|
node.setAttribute(key, value)
|
|
if node.hasChildNodes():
|
|
for child in node.childNodes:
|
|
superAppendAttribute(child, key, value)
|
|
|
|
def gatherTextNodes(iNode, dounescape=0, joinWith=""):
|
|
"""Visit each child node and collect its text data, if any, into a string.
|
|
For example::
|
|
>>> doc=microdom.parseString('<a>1<b>2<c>3</c>4</b></a>')
|
|
>>> gatherTextNodes(doc.documentElement)
|
|
'1234'
|
|
With dounescape=1, also convert entities back into normal characters.
|
|
@return: the gathered nodes as a single string
|
|
@rtype: str
|
|
"""
|
|
gathered=[]
|
|
gathered_append=gathered.append
|
|
slice=[iNode]
|
|
while len(slice)>0:
|
|
c=slice.pop(0)
|
|
if hasattr(c, 'nodeValue') and c.nodeValue is not None:
|
|
if dounescape:
|
|
val=unescape(c.nodeValue)
|
|
else:
|
|
val=c.nodeValue
|
|
gathered_append(val)
|
|
slice[:0]=c.childNodes
|
|
return joinWith.join(gathered)
|
|
|
|
class RawText(microdom.Text):
|
|
"""This is an evil and horrible speed hack. Basically, if you have a big
|
|
chunk of XML that you want to insert into the DOM, but you don't want to
|
|
incur the cost of parsing it, you can construct one of these and insert it
|
|
into the DOM. This will most certainly only work with microdom as the API
|
|
for converting nodes to xml is different in every DOM implementation.
|
|
|
|
This could be improved by making this class a Lazy parser, so if you
|
|
inserted this into the DOM and then later actually tried to mutate this
|
|
node, it would be parsed then.
|
|
"""
|
|
|
|
def writexml(self, writer, indent="", addindent="", newl="", strip=0, nsprefixes=None, namespace=None):
|
|
writer.write("%s%s%s" % (indent, self.data, newl))
|
|
|
|
def findNodes(parent, matcher, accum=None):
|
|
if accum is None:
|
|
accum = []
|
|
if not parent.hasChildNodes():
|
|
return accum
|
|
for child in parent.childNodes:
|
|
# print child, child.nodeType, child.nodeName
|
|
if matcher(child):
|
|
accum.append(child)
|
|
findNodes(child, matcher, accum)
|
|
return accum
|
|
|
|
|
|
def findNodesShallowOnMatch(parent, matcher, recurseMatcher, accum=None):
|
|
if accum is None:
|
|
accum = []
|
|
if not parent.hasChildNodes():
|
|
return accum
|
|
for child in parent.childNodes:
|
|
# print child, child.nodeType, child.nodeName
|
|
if matcher(child):
|
|
accum.append(child)
|
|
if recurseMatcher(child):
|
|
findNodesShallowOnMatch(child, matcher, recurseMatcher, accum)
|
|
return accum
|
|
|
|
def findNodesShallow(parent, matcher, accum=None):
|
|
if accum is None:
|
|
accum = []
|
|
if not parent.hasChildNodes():
|
|
return accum
|
|
for child in parent.childNodes:
|
|
if matcher(child):
|
|
accum.append(child)
|
|
else:
|
|
findNodes(child, matcher, accum)
|
|
return accum
|
|
|
|
|
|
def findElementsWithAttributeShallow(parent, attribute):
|
|
"""
|
|
Return an iterable of the elements which are direct children of C{parent}
|
|
and which have the C{attribute} attribute.
|
|
"""
|
|
return findNodesShallow(parent,
|
|
lambda n: getattr(n, 'tagName', None) is not None and
|
|
n.hasAttribute(attribute))
|
|
|
|
|
|
def findElements(parent, matcher):
|
|
"""
|
|
Return an iterable of the elements which are children of C{parent} for
|
|
which the predicate C{matcher} returns true.
|
|
"""
|
|
return findNodes(
|
|
parent,
|
|
lambda n, matcher=matcher: getattr(n, 'tagName', None) is not None and
|
|
matcher(n))
|
|
|
|
def findElementsWithAttribute(parent, attribute, value=None):
|
|
if value:
|
|
return findElements(
|
|
parent,
|
|
lambda n, attribute=attribute, value=value:
|
|
n.hasAttribute(attribute) and n.getAttribute(attribute) == value)
|
|
else:
|
|
return findElements(
|
|
parent,
|
|
lambda n, attribute=attribute: n.hasAttribute(attribute))
|
|
|
|
|
|
def findNodesNamed(parent, name):
|
|
return findNodes(parent, lambda n, name=name: n.nodeName == name)
|
|
|
|
|
|
def writeNodeData(node, oldio):
|
|
for subnode in node.childNodes:
|
|
if hasattr(subnode, 'data'):
|
|
oldio.write(subnode.data)
|
|
else:
|
|
writeNodeData(subnode, oldio)
|
|
|
|
|
|
def getNodeText(node):
|
|
oldio = StringIO.StringIO()
|
|
writeNodeData(node, oldio)
|
|
return oldio.getvalue()
|
|
|
|
|
|
def getParents(node):
|
|
l = []
|
|
while node:
|
|
l.append(node)
|
|
node = node.parentNode
|
|
return l
|
|
|
|
def namedChildren(parent, nodeName):
|
|
"""namedChildren(parent, nodeName) -> children (not descendants) of parent
|
|
that have tagName == nodeName
|
|
"""
|
|
return [n for n in parent.childNodes if getattr(n, 'tagName', '')==nodeName]
|