xmldicts.py

from lxml import etree


def node_from_dict(tag, data=None):
    node = etree.Element(tag)
    if isinstance(data, dict):
        for key, value in data.items():
            if isinstance(value, list):
                for v in value:
                    node.append(node_from_dict(key, v))
            else:
                node.append(node_from_dict(key, value))
    else:
        node.text = data
    return node


def dict_from_nodes(nodes):
    data = {}
    for node in nodes:
        children = node.getchildren()
        key = node.tag
        value = dict_from_nodes(children) if children else node.text

        if key not in data:
            data[key] = value
        elif not isinstance(data[key], list):
            data[key] = [data[key], value]
        else:
            data[key].append(value)
    return data

Example usage:

>>> xml = "<?xml version='1.0' encoding='ASCII'?>\n<response><bleh>TRUE</bleh><foo>bar</foo><foo>qux</foo></response>"
>>> node = etree.fromstring(xml)
>>> data = dict_from_nodes(node.getchildren())
>>> data['foo']
['bar', 'qux']
>>> node = node_from_dict('response', data)
>>> xml == etree.tostring(node, xml_declaration=True)
True

License: CC0 http://creativecommons.org/publicdomain/zero/1.0/