Lib/xml/dom/minidom.py

Source:

cpython 3.14 @ ab2d84fe1023/Lib/xml/dom/minidom.py ↗

xml.dom.minidom is a lightweight DOM (Document Object Model) implementation. It is primarily used for generating and modifying XML documents.

Map

Lines	Symbol	Role
1-100	Node	Base class: nodeType, parentNode, childNodes, firstChild
101-300	Document	Root node: documentElement, createElement, createTextNode
301-600	Element	tagName, getAttribute, setAttribute, appendChild
601-800	Text, Comment, CDATA	Leaf node types
801-1000	Attr	Attribute node: name, value
1001-1300	parse, parseString	SAX-driven parsing into DOM tree
1301-1600	toxml, toprettyxml	Serialize DOM back to XML string
1601-1900	Namespace support	createElementNS, createAttributeNS

Reading

Node tree

# CPython: Lib/xml/dom/minidom.py:55 Node
class Node(xml.dom.Node):
    namespaceURI = None
    parentNode = None
    ownerDocument = None
    nextSibling = None
    previousSibling = None

    def insertBefore(self, newChild, refChild):
        ...
        if refChild is None:
            return self.appendChild(newChild)
        ...

parse and parseString

# CPython: Lib/xml/dom/minidom.py:1040 parse
def parse(file, parser=None, bufsize=None):
    """Return a Document from the given input.
    Uses expat via xml.sax under the hood.
    """
    if isinstance(file, str):
        with open(file, 'rb') as fp:
            return _do_pulldom_parse(fp.read(), parser)
    return _do_pulldom_parse(file.read(), parser)

def parseString(string, parser=None):
    return _do_pulldom_parse(string, parser)

Both functions use xml.dom.pulldom which drives a SAX parser and builds the DOM lazily.

Element.getAttribute

# CPython: Lib/xml/dom/minidom.py:480 getAttribute
def getAttribute(self, attname):
    try:
        return self._attrs[attname].value
    except KeyError:
        return ""

Attributes are stored in _attrs = {} (a dict mapping name to Attr nodes). Missing attributes return "" per DOM spec.

toxml

# CPython: Lib/xml/dom/minidom.py:1350 toxml
def toxml(self, encoding=None, standalone=None):
    """Return the XML as a string.
    If encoding is given, return bytes; otherwise return str.
    """
    writer = io.StringIO()
    if self.nodeType == Node.DOCUMENT_NODE:
        self.writexml(writer, encoding=encoding, standalone=standalone)
    else:
        self.writexml(writer)
    return writer.getvalue()

toprettyxml

# CPython: Lib/xml/dom/minidom.py:1395 toprettyxml
def toprettyxml(self, indent="\t", newl="\n", encoding=None, standalone=None):
    """Return indented XML.
    Adds whitespace-only text nodes to simulate indentation.
    """
    ...

toprettyxml adds whitespace text nodes, which can cause issues if the original document used mixed content (text + elements). For pure structured data it works well.

gopy notes

xml.dom.minidom is pure Python and importable when xml.sax, xml.dom, io, and codecs work. The DOM tree is plain Python objects with no C acceleration. For high-performance XML, xml.etree.ElementTree (Modules/_elementtree.c) is preferred.