Source code for taf.testlib.xmltodict

#!/usr/bin/env python

from xml.parsers import expat
from xml.sax.saxutils import XMLGenerator
from xml.sax.xmlreader import AttributesImpl

"Makes working with XML feel like you are working with JSON"
"""
Copyright (C) 2012 Martin Blech and individual contributors.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
"""


try:  # pragma no cover
    from io import StringIO
except ImportError:  # pragma no cover
    try:
        from io import StringIO
    except ImportError:
        from io import StringIO
try:  # pragma no cover
    from collections import OrderedDict
except ImportError:  # pragma no cover
    OrderedDict = dict

try:  # pragma no cover
    _basestring = str
except NameError:  # pragma no cover
    _basestring = str
try:  # pragma no cover
    _unicode = str
except NameError:  # pragma no cover
    _unicode = str

__author__ = 'Martin Blech'
__version__ = '0.5.0'
__license__ = 'MIT'


[docs]class ParsingInterrupted(Exception): pass
class _DictSAXHandler(object): def __init__(self, item_depth=0, item_callback=lambda *args: True, xml_attribs=True, attr_prefix='@', cdata_key='#text', force_cdata=False, cdata_separator='', postprocessor=None, dict_constructor=OrderedDict, strip_whitespace=True): self.path = [] self.stack = [] self.data = None self.item = None self.item_depth = item_depth self.xml_attribs = xml_attribs self.item_callback = item_callback self.attr_prefix = attr_prefix self.cdata_key = cdata_key self.force_cdata = force_cdata self.cdata_separator = cdata_separator self.postprocessor = postprocessor self.dict_constructor = dict_constructor self.strip_whitespace = strip_whitespace def startElement(self, name, attrs): attrs = self.dict_constructor(list(zip(attrs[0::2], attrs[1::2]))) self.path.append((name, attrs or None)) if len(self.path) > self.item_depth: self.stack.append((self.item, self.data)) if self.xml_attribs: attrs = self.dict_constructor( (self.attr_prefix+key, value) for (key, value) in list(attrs.items())) else: attrs = None self.item = attrs or None self.data = None def endElement(self, name): if len(self.path) == self.item_depth: item = self.item if item is None: item = self.data should_continue = self.item_callback(self.path, item) if not should_continue: raise ParsingInterrupted() if len(self.stack): item, data = self.item, self.data self.item, self.data = self.stack.pop() if self.strip_whitespace and data is not None: data = data.strip() or None if data and self.force_cdata and item is None: item = self.dict_constructor() if item is not None: if data: self.push_data(item, self.cdata_key, data) self.item = self.push_data(self.item, name, item) else: self.item = self.push_data(self.item, name, data) else: self.item = self.data = None self.path.pop() def characters(self, data): if not self.data: self.data = data else: self.data += self.cdata_separator + data def push_data(self, item, key, data): if self.postprocessor is not None: result = self.postprocessor(self.path, key, data) if result is None: return item key, data = result if item is None: item = self.dict_constructor() try: value = item[key] if isinstance(value, list): value.append(data) else: item[key] = [value, data] except KeyError: item[key] = data return item
[docs]def parse(xml_input, encoding='utf-8', expat=expat, *args, **kwargs): """Parse the given XML input and convert it into a dictionary. `xml_input` can either be a `string` or a file-like object. If `xml_attribs` is `True`, element attributes are put in the dictionary among regular child elements, using `@` as a prefix to avoid collisions. If set to `False`, they are just ignored. Simple example:: >>> doc = xmltodict.parse(\"\"\" ... <a prop="x"> ... <b>1</b> ... <b>2</b> ... </a> ... \"\"\") >>> doc['a']['@property'] u'x' >>> doc['a']['b'] [u'1', u'2'] If `item_depth` is `0`, the function returns a dictionary for the root element (default behavior). Otherwise, it calls `item_callback` every time an item at the specified depth is found and returns `None` in the end (streaming mode). The callback function receives two parameters: the `path` from the document root to the item (name-attribs pairs), and the `item` (dict). If the callback's return value is false-ish, parsing will be stopped with the :class:`ParsingInterrupted` exception. Streaming example:: >>> def handle(path, item): ... print 'path:%s item:%s' % (path, item) ... return True ... >>> xmltodict.parse(\"\"\" ... <a prop="x"> ... <b>1</b> ... <b>2</b> ... </a>\"\"\", item_depth=2, item_callback=handle) path:[(u'a', {u'prop': u'x'}), (u'b', None)] item:1 path:[(u'a', {u'prop': u'x'}), (u'b', None)] item:2 The optional argument `postprocessor` is a function that takes `path`, `key` and `value` as positional arguments and returns a new `(key, value)` pair where both `key` and `value` may have changed. Usage example:: >>> def postprocessor(path, key, value): ... try: ... return key + ':int', int(value) ... except (ValueError, TypeError): ... return key, value >>> xmltodict.parse('<a><b>1</b><b>2</b><b>x</b></a>', ... postprocessor=postprocessor) OrderedDict([(u'a', OrderedDict([(u'b:int', [1, 2]), (u'b', u'x')]))]) You can pass an alternate version of `expat` (such as `defusedexpat`) by using the `expat` parameter. E.g: >>> import defusedexpat >>> xmltodict.parse('<a>hello</a>', expat=defusedexpat.pyexpat) OrderedDict([(u'a', u'hello')]) """ handler = _DictSAXHandler(*args, **kwargs) parser = expat.ParserCreate() parser.ordered_attributes = True parser.StartElementHandler = handler.startElement parser.EndElementHandler = handler.endElement parser.CharacterDataHandler = handler.characters try: parser.ParseFile(xml_input) except (TypeError, AttributeError): if isinstance(xml_input, _unicode): xml_input = xml_input.encode(encoding) parser.Parse(xml_input, True) return handler.item
def _emit(key, value, content_handler, attr_prefix='@', cdata_key='#text', root=True, preprocessor=None): if preprocessor is not None: result = preprocessor(key, value) if result is None: return key, value = result if not isinstance(value, (list, tuple)): value = [value] if root and len(value) > 1: raise ValueError('document with multiple roots') for v in value: if v is None: v = OrderedDict() elif not isinstance(v, dict): v = _unicode(v) if isinstance(v, _basestring): v = OrderedDict(((cdata_key, v),)) cdata = None attrs = OrderedDict() children = [] for ik, iv in list(v.items()): if ik == cdata_key: cdata = iv continue if ik.startswith(attr_prefix): attrs[ik[len(attr_prefix):]] = iv continue children.append((ik, iv)) content_handler.startElement(key, AttributesImpl(attrs)) for child_key, child_value in children: _emit(child_key, child_value, content_handler, attr_prefix, cdata_key, False, preprocessor) if cdata is not None: content_handler.characters(cdata) content_handler.endElement(key)
[docs]def unparse(item, output=None, encoding='utf-8', **kwargs): ((key, value),) = list(item.items()) must_return = False if output is None: output = StringIO() must_return = True content_handler = XMLGenerator(output, encoding) content_handler.startDocument() _emit(key, value, content_handler, **kwargs) content_handler.endDocument() if must_return: value = output.getvalue() try: # pragma no cover value = value.decode(encoding) except AttributeError: # pragma no cover pass return value
if __name__ == '__main__': # pragma: no cover import sys import marshal (item_depth,) = sys.argv[1:] item_depth = int(item_depth) def handle_item(path, item): marshal.dump((path, item), sys.stdout) return True try: root = parse(sys.stdin, item_depth=item_depth, item_callback=handle_item, dict_constructor=dict) if item_depth == 0: handle_item([], root) except KeyboardInterrupt: pass