minidom.py

Python Development Environment (Python IDE plugin for Eclipse). Features editor, code completion, re

"""\
minidom.py -- a lightweight DOM implementation.

parse("foo.xml")

parseString("<foo><bar/></foo>")

Todo:
=====
 * convenience methods for getting elements and text.
 * more testing
 * bring some of the writer and linearizer code into conformance with this
        interface
 * SAX 2 namespaces
"""

import string
_string = string
del string

from xml.dom import HierarchyRequestErr

# localize the types, and allow support for Unicode values if available:
import types
_TupleType = types.TupleType
try:
    _StringTypes = (types.StringType, types.UnicodeType)
except AttributeError:
    _StringTypes = (types.StringType,)
del types

import xml.dom
_Node = xml.dom.Node

class Node(_Node):
    allnodes = {}
    _debug = 0
    _makeParentNodes = 1
    debug = None
    childNodeTypes = ()
    namespaceURI = None # this is non-null only for elements and attributes

    def __init__(self):
        self.childNodes = []
        self.parentNode = self.ownerDocument = None
        if Node._debug:
            index = repr(id(self)) + repr(self.__class__)
            Node.allnodes[index] = repr(self.__dict__)
            if Node.debug is None:
                Node.debug = _get_StringIO()
                #open("debug4.out", "w")
            Node.debug.write("create %s\n" % index)

    def __getattr__(self, key):
        if key[0:2] == "__":
            raise AttributeError, key
        # getattr should never call getattr!
        if self.__dict__.has_key("inGetAttr"):
            del self.inGetAttr
            raise AttributeError, key

        prefix, attrname = key[:5], key[5:]
        if prefix == "_get_":
            self.inGetAttr = 1
            if hasattr(self, attrname):
                del self.inGetAttr
                return (lambda self=self, attrname=attrname:
                                getattr(self, attrname))
            else:
                del self.inGetAttr
                raise AttributeError, key
        else:
            self.inGetAttr = 1
            try:
                func = getattr(self, "_get_" + key)
            except AttributeError:
                raise AttributeError, key
            del self.inGetAttr
            return func()

    def __nonzero__(self):
        return 1

    def toxml(self):
        writer = _get_StringIO()
        self.writexml(writer)
        return writer.getvalue()

    def toprettyxml(self, indent="\t", newl="\n"):
        # indent = the indentation string to prepend, per level
        # newl = the newline string to append
        writer = _get_StringIO()
        self.writexml(writer, "", indent, newl)
        return writer.getvalue()

    def hasChildNodes(self):
        if self.childNodes:
            return 1
        else:
            return 0

    def _get_firstChild(self):
        if self.childNodes:
            return self.childNodes[0]

    def _get_lastChild(self):
        if self.childNodes:
            return self.childNodes[-1]

    def insertBefore(self, newChild, refChild):
        if newChild.nodeType == self.DOCUMENT_FRAGMENT_NODE:
            for c in newChild.childNodes:
                self.insertBefore(c, refChild)
            ### The DOM does not clearly specify what to return in this case
            return newChild
        if newChild.nodeType not in self.childNodeTypes:
            raise HierarchyRequestErr, \
                  "%s cannot be child of %s" % (repr(newChild), repr(self))
        if newChild.parentNode is not None:
            newChild.parentNode.removeChild(newChild)
        if refChild is None:
            self.appendChild(newChild)
        else:
            index = self.childNodes.index(refChild)
            self.childNodes.insert(index, newChild)
            newChild.nextSibling = refChild
            refChild.previousSibling = newChild
            if index:
                node = self.childNodes[index-1]
                node.nextSibling = newChild
                newChild.previousSibling = node
            else:
                newChild.previousSibling = None
            if self._makeParentNodes:
                newChild.parentNode = self
        return newChild

    def appendChild(self, node):
        if node.nodeType == self.DOCUMENT_FRAGMENT_NODE:
            for c in node.childNodes:
                self.appendChild(c)
            ### The DOM does not clearly specify what to return in this case
            return node
        if node.nodeType not in self.childNodeTypes:
            raise HierarchyRequestErr, \
                  "%s cannot be child of %s" % (repr(node), repr(self))
        if node.parentNode is not None:
            node.parentNode.removeChild(node)
        if self.childNodes:
            last = self.lastChild
            node.previousSibling = last
            last.nextSibling = node
        else:
            node.previousSibling = None
        node.nextSibling = None
        self.childNodes.append(node)
        if self._makeParentNodes:
            node.parentNode = self
        return node

    def replaceChild(self, newChild, oldChild):
        if newChild.nodeType == self.DOCUMENT_FRAGMENT_NODE:
            refChild = oldChild.nextSibling
            self.removeChild(oldChild)
            return self.insertBefore(newChild, refChild)
        if newChild.nodeType not in self.childNodeTypes:
            raise HierarchyRequestErr, \
                  "%s cannot be child of %s" % (repr(newChild), repr(self))
        if newChild.parentNode is not None:
            newChild.parentNode.removeChild(newChild)
        if newChild is oldChild:
            return
        index = self.childNodes.index(oldChild)
        self.childNodes[index] = newChild
        if self._makeParentNodes:
            newChild.parentNode = self
            oldChild.parentNode = None
        newChild.nextSibling = oldChild.nextSibling
        newChild.previousSibling = oldChild.previousSibling
        oldChild.nextSibling = None
        oldChild.previousSibling = None
        if newChild.previousSibling:
            newChild.previousSibling.nextSibling = newChild
        if newChild.nextSibling:
            newChild.nextSibling.previousSibling = newChild
        return oldChild

    def removeChild(self, oldChild):
        self.childNodes.remove(oldChild)
        if oldChild.nextSibling is not None:
            oldChild.nextSibling.previousSibling = oldChild.previousSibling
        if oldChild.previousSibling is not None:
            oldChild.previousSibling.nextSibling = oldChild.nextSibling
        oldChild.nextSibling = oldChild.previousSibling = None

        if self._makeParentNodes:
            oldChild.parentNode = None
        return oldChild

    def normalize(self):
        L = []
        for child in self.childNodes:
            if child.nodeType == Node.TEXT_NODE:
                data = child.data
                if data and L and L[-1].nodeType == child.nodeType:
                    # collapse text node
                    node = L[-1]
                    node.data = node.nodeValue = node.data + child.data
                    node.nextSibling = child.nextSibling
                    child.unlink()
                elif data:
                    if L:
                        L[-1].nextSibling = child
                        child.previousSibling = L[-1]
                    else:
                        child.previousSibling = None
                    L.append(child)
                else:
                    # empty text node; discard
                    child.unlink()
            else:
                if L:
                    L[-1].nextSibling = child
                    child.previousSibling = L[-1]
                else:
                    child.previousSibling = None
                L.append(child)
                if child.nodeType == Node.ELEMENT_NODE:
                    child.normalize()
        self.childNodes[:] = L

    def cloneNode(self, deep):
        import new
        clone = new.instance(self.__class__, self.__dict__.copy())
        if self._makeParentNodes:
            clone.parentNode = None
        clone.childNodes = []
        if deep:
            for child in self.childNodes:
                clone.appendChild(child.cloneNode(1))
        return clone

    # DOM Level 3 (Working Draft 2001-Jan-26)

    def isSameNode(self, other):
        return self is other

    # minidom-specific API:

    def unlink(self):
        self.parentNode = self.ownerDocument = None
        for child in self.childNodes:
            child.unlink()
        self.childNodes = None
        self.previousSibling = None
        self.nextSibling = None
        if Node._debug:
            index = repr(id(self)) + repr(self.__class__)
            self.debug.write("Deleting: %s\n" % index)
            del Node.allnodes[index]

def _write_data(writer, data):
    "Writes datachars to writer."
    replace = _string.replace
    data = replace(data, "&", "&amp;")
    data = replace(data, "<", "&lt;")
    data = replace(data, "\"", "&quot;")
    data = replace(data, ">", "&gt;")
    writer.write(data)

def _getElementsByTagNameHelper(parent, name, rc):
    for node in parent.childNodes:
        if node.nodeType == Node.ELEMENT_NODE and \
            (name == "*" or node.tagName == name):
            rc.append(node)
        _getElementsByTagNameHelper(node, name, rc)
    return rc

def _getElementsByTagNameNSHelper(parent, nsURI, localName, rc):
    for node in parent.childNodes:
        if node.nodeType == Node.ELEMENT_NODE:
            if ((localName == "*" or node.localName == localName) and
                (nsURI == "*" or node.namespaceURI == nsURI)):
                rc.append(node)
            _getElementsByTagNameNSHelper(node, nsURI, localName, rc)
    return rc

class DocumentFragment(Node):
    nodeType = Node.DOCUMENT_FRAGMENT_NODE
    nodeName = "#document-fragment"
    nodeValue = None
    attributes = None
    parentNode = None
    childNodeTypes = (Node.ELEMENT_NODE,
                      Node.TEXT_NODE,
                      Node.CDATA_SECTION_NODE,
                      Node.ENTITY_REFERENCE_NODE,
                      Node.PROCESSING_INSTRUCTION_NODE,
                      Node.COMMENT_NODE,
                      Node.NOTATION_NODE)


class Attr(Node):
    nodeType = Node.ATTRIBUTE_NODE
    attributes = None
    ownerElement = None