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44b548dda8
And most of the tools. Patch by Emanual Barry, reviewed by me, Serhiy Storchaka, and Martin Panter.
1645 lines
55 KiB
Python
1645 lines
55 KiB
Python
"""Lightweight XML support for Python.
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XML is an inherently hierarchical data format, and the most natural way to
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represent it is with a tree. This module has two classes for this purpose:
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1. ElementTree represents the whole XML document as a tree and
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2. Element represents a single node in this tree.
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Interactions with the whole document (reading and writing to/from files) are
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usually done on the ElementTree level. Interactions with a single XML element
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and its sub-elements are done on the Element level.
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Element is a flexible container object designed to store hierarchical data
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structures in memory. It can be described as a cross between a list and a
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dictionary. Each Element has a number of properties associated with it:
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'tag' - a string containing the element's name.
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'attributes' - a Python dictionary storing the element's attributes.
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'text' - a string containing the element's text content.
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'tail' - an optional string containing text after the element's end tag.
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And a number of child elements stored in a Python sequence.
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To create an element instance, use the Element constructor,
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or the SubElement factory function.
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You can also use the ElementTree class to wrap an element structure
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and convert it to and from XML.
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"""
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#---------------------------------------------------------------------
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# Licensed to PSF under a Contributor Agreement.
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# See http://www.python.org/psf/license for licensing details.
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#
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# ElementTree
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# Copyright (c) 1999-2008 by Fredrik Lundh. All rights reserved.
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#
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# fredrik@pythonware.com
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# http://www.pythonware.com
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# --------------------------------------------------------------------
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# The ElementTree toolkit is
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#
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# Copyright (c) 1999-2008 by Fredrik Lundh
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#
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# By obtaining, using, and/or copying this software and/or its
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# associated documentation, you agree that you have read, understood,
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# and will comply with the following terms and conditions:
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#
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# Permission to use, copy, modify, and distribute this software and
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# its associated documentation for any purpose and without fee is
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# hereby granted, provided that the above copyright notice appears in
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# all copies, and that both that copyright notice and this permission
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# notice appear in supporting documentation, and that the name of
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# Secret Labs AB or the author not be used in advertising or publicity
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# pertaining to distribution of the software without specific, written
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# prior permission.
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#
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# SECRET LABS AB AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD
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# TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANT-
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# ABILITY AND FITNESS. IN NO EVENT SHALL SECRET LABS AB OR THE AUTHOR
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# BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
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# DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
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# WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
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# ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
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# OF THIS SOFTWARE.
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# --------------------------------------------------------------------
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__all__ = [
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# public symbols
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"Comment",
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"dump",
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"Element", "ElementTree",
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"fromstring", "fromstringlist",
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"iselement", "iterparse",
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"parse", "ParseError",
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"PI", "ProcessingInstruction",
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"QName",
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"SubElement",
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"tostring", "tostringlist",
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"TreeBuilder",
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"VERSION",
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"XML", "XMLID",
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"XMLParser", "XMLPullParser",
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"register_namespace",
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]
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VERSION = "1.3.0"
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import sys
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import re
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import warnings
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import io
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import collections
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import contextlib
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from . import ElementPath
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class ParseError(SyntaxError):
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"""An error when parsing an XML document.
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In addition to its exception value, a ParseError contains
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two extra attributes:
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'code' - the specific exception code
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'position' - the line and column of the error
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"""
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pass
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# --------------------------------------------------------------------
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def iselement(element):
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"""Return True if *element* appears to be an Element."""
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return hasattr(element, 'tag')
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class Element:
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"""An XML element.
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This class is the reference implementation of the Element interface.
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An element's length is its number of subelements. That means if you
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want to check if an element is truly empty, you should check BOTH
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its length AND its text attribute.
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The element tag, attribute names, and attribute values can be either
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bytes or strings.
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*tag* is the element name. *attrib* is an optional dictionary containing
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element attributes. *extra* are additional element attributes given as
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keyword arguments.
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Example form:
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<tag attrib>text<child/>...</tag>tail
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"""
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tag = None
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"""The element's name."""
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attrib = None
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"""Dictionary of the element's attributes."""
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text = None
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"""
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Text before first subelement. This is either a string or the value None.
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Note that if there is no text, this attribute may be either
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None or the empty string, depending on the parser.
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"""
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tail = None
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"""
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Text after this element's end tag, but before the next sibling element's
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start tag. This is either a string or the value None. Note that if there
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was no text, this attribute may be either None or an empty string,
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depending on the parser.
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"""
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def __init__(self, tag, attrib={}, **extra):
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if not isinstance(attrib, dict):
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raise TypeError("attrib must be dict, not %s" % (
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attrib.__class__.__name__,))
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attrib = attrib.copy()
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attrib.update(extra)
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self.tag = tag
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self.attrib = attrib
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self._children = []
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def __repr__(self):
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return "<%s %r at %#x>" % (self.__class__.__name__, self.tag, id(self))
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def makeelement(self, tag, attrib):
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"""Create a new element with the same type.
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*tag* is a string containing the element name.
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*attrib* is a dictionary containing the element attributes.
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Do not call this method, use the SubElement factory function instead.
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"""
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return self.__class__(tag, attrib)
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def copy(self):
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"""Return copy of current element.
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This creates a shallow copy. Subelements will be shared with the
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original tree.
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"""
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elem = self.makeelement(self.tag, self.attrib)
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elem.text = self.text
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elem.tail = self.tail
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elem[:] = self
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return elem
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def __len__(self):
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return len(self._children)
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def __bool__(self):
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warnings.warn(
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"The behavior of this method will change in future versions. "
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"Use specific 'len(elem)' or 'elem is not None' test instead.",
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FutureWarning, stacklevel=2
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)
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return len(self._children) != 0 # emulate old behaviour, for now
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def __getitem__(self, index):
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return self._children[index]
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def __setitem__(self, index, element):
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# if isinstance(index, slice):
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# for elt in element:
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# assert iselement(elt)
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# else:
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# assert iselement(element)
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self._children[index] = element
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def __delitem__(self, index):
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del self._children[index]
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def append(self, subelement):
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"""Add *subelement* to the end of this element.
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The new element will appear in document order after the last existing
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subelement (or directly after the text, if it's the first subelement),
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but before the end tag for this element.
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"""
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self._assert_is_element(subelement)
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self._children.append(subelement)
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def extend(self, elements):
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"""Append subelements from a sequence.
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*elements* is a sequence with zero or more elements.
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"""
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for element in elements:
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self._assert_is_element(element)
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self._children.extend(elements)
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def insert(self, index, subelement):
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"""Insert *subelement* at position *index*."""
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self._assert_is_element(subelement)
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self._children.insert(index, subelement)
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def _assert_is_element(self, e):
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# Need to refer to the actual Python implementation, not the
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# shadowing C implementation.
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if not isinstance(e, _Element_Py):
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raise TypeError('expected an Element, not %s' % type(e).__name__)
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def remove(self, subelement):
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"""Remove matching subelement.
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Unlike the find methods, this method compares elements based on
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identity, NOT ON tag value or contents. To remove subelements by
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other means, the easiest way is to use a list comprehension to
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select what elements to keep, and then use slice assignment to update
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the parent element.
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ValueError is raised if a matching element could not be found.
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"""
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# assert iselement(element)
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self._children.remove(subelement)
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def getchildren(self):
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"""(Deprecated) Return all subelements.
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Elements are returned in document order.
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"""
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warnings.warn(
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"This method will be removed in future versions. "
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"Use 'list(elem)' or iteration over elem instead.",
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DeprecationWarning, stacklevel=2
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)
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return self._children
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def find(self, path, namespaces=None):
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"""Find first matching element by tag name or path.
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*path* is a string having either an element tag or an XPath,
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*namespaces* is an optional mapping from namespace prefix to full name.
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Return the first matching element, or None if no element was found.
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"""
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return ElementPath.find(self, path, namespaces)
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def findtext(self, path, default=None, namespaces=None):
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"""Find text for first matching element by tag name or path.
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*path* is a string having either an element tag or an XPath,
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*default* is the value to return if the element was not found,
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*namespaces* is an optional mapping from namespace prefix to full name.
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Return text content of first matching element, or default value if
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none was found. Note that if an element is found having no text
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content, the empty string is returned.
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"""
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return ElementPath.findtext(self, path, default, namespaces)
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def findall(self, path, namespaces=None):
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"""Find all matching subelements by tag name or path.
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*path* is a string having either an element tag or an XPath,
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*namespaces* is an optional mapping from namespace prefix to full name.
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Returns list containing all matching elements in document order.
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"""
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return ElementPath.findall(self, path, namespaces)
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def iterfind(self, path, namespaces=None):
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"""Find all matching subelements by tag name or path.
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*path* is a string having either an element tag or an XPath,
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*namespaces* is an optional mapping from namespace prefix to full name.
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Return an iterable yielding all matching elements in document order.
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"""
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return ElementPath.iterfind(self, path, namespaces)
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def clear(self):
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"""Reset element.
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This function removes all subelements, clears all attributes, and sets
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the text and tail attributes to None.
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"""
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self.attrib.clear()
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self._children = []
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self.text = self.tail = None
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def get(self, key, default=None):
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"""Get element attribute.
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Equivalent to attrib.get, but some implementations may handle this a
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bit more efficiently. *key* is what attribute to look for, and
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*default* is what to return if the attribute was not found.
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Returns a string containing the attribute value, or the default if
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attribute was not found.
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"""
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return self.attrib.get(key, default)
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def set(self, key, value):
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"""Set element attribute.
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Equivalent to attrib[key] = value, but some implementations may handle
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this a bit more efficiently. *key* is what attribute to set, and
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*value* is the attribute value to set it to.
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"""
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self.attrib[key] = value
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def keys(self):
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"""Get list of attribute names.
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Names are returned in an arbitrary order, just like an ordinary
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Python dict. Equivalent to attrib.keys()
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"""
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return self.attrib.keys()
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def items(self):
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"""Get element attributes as a sequence.
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The attributes are returned in arbitrary order. Equivalent to
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attrib.items().
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Return a list of (name, value) tuples.
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"""
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return self.attrib.items()
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def iter(self, tag=None):
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"""Create tree iterator.
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The iterator loops over the element and all subelements in document
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order, returning all elements with a matching tag.
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If the tree structure is modified during iteration, new or removed
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elements may or may not be included. To get a stable set, use the
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list() function on the iterator, and loop over the resulting list.
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*tag* is what tags to look for (default is to return all elements)
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Return an iterator containing all the matching elements.
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"""
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if tag == "*":
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tag = None
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if tag is None or self.tag == tag:
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yield self
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for e in self._children:
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yield from e.iter(tag)
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# compatibility
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def getiterator(self, tag=None):
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# Change for a DeprecationWarning in 1.4
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warnings.warn(
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"This method will be removed in future versions. "
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"Use 'elem.iter()' or 'list(elem.iter())' instead.",
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PendingDeprecationWarning, stacklevel=2
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)
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return list(self.iter(tag))
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def itertext(self):
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"""Create text iterator.
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The iterator loops over the element and all subelements in document
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order, returning all inner text.
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"""
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tag = self.tag
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if not isinstance(tag, str) and tag is not None:
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return
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t = self.text
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if t:
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yield t
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for e in self:
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yield from e.itertext()
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t = e.tail
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if t:
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yield t
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def SubElement(parent, tag, attrib={}, **extra):
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"""Subelement factory which creates an element instance, and appends it
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to an existing parent.
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The element tag, attribute names, and attribute values can be either
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bytes or Unicode strings.
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*parent* is the parent element, *tag* is the subelements name, *attrib* is
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an optional directory containing element attributes, *extra* are
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additional attributes given as keyword arguments.
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"""
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attrib = attrib.copy()
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attrib.update(extra)
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element = parent.makeelement(tag, attrib)
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parent.append(element)
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return element
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def Comment(text=None):
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"""Comment element factory.
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This function creates a special element which the standard serializer
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serializes as an XML comment.
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*text* is a string containing the comment string.
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"""
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element = Element(Comment)
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element.text = text
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return element
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|
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def ProcessingInstruction(target, text=None):
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"""Processing Instruction element factory.
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This function creates a special element which the standard serializer
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serializes as an XML comment.
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*target* is a string containing the processing instruction, *text* is a
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string containing the processing instruction contents, if any.
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"""
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element = Element(ProcessingInstruction)
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element.text = target
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if text:
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element.text = element.text + " " + text
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return element
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PI = ProcessingInstruction
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|
|
|
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class QName:
|
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"""Qualified name wrapper.
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|
|
This class can be used to wrap a QName attribute value in order to get
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proper namespace handing on output.
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|
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*text_or_uri* is a string containing the QName value either in the form
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{uri}local, or if the tag argument is given, the URI part of a QName.
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|
*tag* is an optional argument which if given, will make the first
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argument (text_or_uri) be interpreted as a URI, and this argument (tag)
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be interpreted as a local name.
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|
"""
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def __init__(self, text_or_uri, tag=None):
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if tag:
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text_or_uri = "{%s}%s" % (text_or_uri, tag)
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self.text = text_or_uri
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def __str__(self):
|
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return self.text
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def __repr__(self):
|
|
return '<%s %r>' % (self.__class__.__name__, self.text)
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|
def __hash__(self):
|
|
return hash(self.text)
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|
def __le__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text <= other.text
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return self.text <= other
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def __lt__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text < other.text
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|
return self.text < other
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def __ge__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text >= other.text
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|
return self.text >= other
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def __gt__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text > other.text
|
|
return self.text > other
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|
def __eq__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text == other.text
|
|
return self.text == other
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|
|
# --------------------------------------------------------------------
|
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|
|
|
|
class ElementTree:
|
|
"""An XML element hierarchy.
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|
|
This class also provides support for serialization to and from
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|
standard XML.
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|
|
*element* is an optional root element node,
|
|
*file* is an optional file handle or file name of an XML file whose
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|
contents will be used to initialize the tree with.
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|
|
"""
|
|
def __init__(self, element=None, file=None):
|
|
# assert element is None or iselement(element)
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self._root = element # first node
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|
if file:
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self.parse(file)
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|
|
def getroot(self):
|
|
"""Return root element of this tree."""
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|
return self._root
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|
|
def _setroot(self, element):
|
|
"""Replace root element of this tree.
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|
|
This will discard the current contents of the tree and replace it
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|
with the given element. Use with care!
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|
|
|
"""
|
|
# assert iselement(element)
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|
self._root = element
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|
|
def parse(self, source, parser=None):
|
|
"""Load external XML document into element tree.
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|
|
*source* is a file name or file object, *parser* is an optional parser
|
|
instance that defaults to XMLParser.
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|
|
ParseError is raised if the parser fails to parse the document.
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|
|
Returns the root element of the given source document.
|
|
|
|
"""
|
|
close_source = False
|
|
if not hasattr(source, "read"):
|
|
source = open(source, "rb")
|
|
close_source = True
|
|
try:
|
|
if parser is None:
|
|
# If no parser was specified, create a default XMLParser
|
|
parser = XMLParser()
|
|
if hasattr(parser, '_parse_whole'):
|
|
# The default XMLParser, when it comes from an accelerator,
|
|
# can define an internal _parse_whole API for efficiency.
|
|
# It can be used to parse the whole source without feeding
|
|
# it with chunks.
|
|
self._root = parser._parse_whole(source)
|
|
return self._root
|
|
while True:
|
|
data = source.read(65536)
|
|
if not data:
|
|
break
|
|
parser.feed(data)
|
|
self._root = parser.close()
|
|
return self._root
|
|
finally:
|
|
if close_source:
|
|
source.close()
|
|
|
|
def iter(self, tag=None):
|
|
"""Create and return tree iterator for the root element.
|
|
|
|
The iterator loops over all elements in this tree, in document order.
|
|
|
|
*tag* is a string with the tag name to iterate over
|
|
(default is to return all elements).
|
|
|
|
"""
|
|
# assert self._root is not None
|
|
return self._root.iter(tag)
|
|
|
|
# compatibility
|
|
def getiterator(self, tag=None):
|
|
# Change for a DeprecationWarning in 1.4
|
|
warnings.warn(
|
|
"This method will be removed in future versions. "
|
|
"Use 'tree.iter()' or 'list(tree.iter())' instead.",
|
|
PendingDeprecationWarning, stacklevel=2
|
|
)
|
|
return list(self.iter(tag))
|
|
|
|
def find(self, path, namespaces=None):
|
|
"""Find first matching element by tag name or path.
|
|
|
|
Same as getroot().find(path), which is Element.find()
|
|
|
|
*path* is a string having either an element tag or an XPath,
|
|
*namespaces* is an optional mapping from namespace prefix to full name.
|
|
|
|
Return the first matching element, or None if no element was found.
|
|
|
|
"""
|
|
# assert self._root is not None
|
|
if path[:1] == "/":
|
|
path = "." + path
|
|
warnings.warn(
|
|
"This search is broken in 1.3 and earlier, and will be "
|
|
"fixed in a future version. If you rely on the current "
|
|
"behaviour, change it to %r" % path,
|
|
FutureWarning, stacklevel=2
|
|
)
|
|
return self._root.find(path, namespaces)
|
|
|
|
def findtext(self, path, default=None, namespaces=None):
|
|
"""Find first matching element by tag name or path.
|
|
|
|
Same as getroot().findtext(path), which is Element.findtext()
|
|
|
|
*path* is a string having either an element tag or an XPath,
|
|
*namespaces* is an optional mapping from namespace prefix to full name.
|
|
|
|
Return the first matching element, or None if no element was found.
|
|
|
|
"""
|
|
# assert self._root is not None
|
|
if path[:1] == "/":
|
|
path = "." + path
|
|
warnings.warn(
|
|
"This search is broken in 1.3 and earlier, and will be "
|
|
"fixed in a future version. If you rely on the current "
|
|
"behaviour, change it to %r" % path,
|
|
FutureWarning, stacklevel=2
|
|
)
|
|
return self._root.findtext(path, default, namespaces)
|
|
|
|
def findall(self, path, namespaces=None):
|
|
"""Find all matching subelements by tag name or path.
|
|
|
|
Same as getroot().findall(path), which is Element.findall().
|
|
|
|
*path* is a string having either an element tag or an XPath,
|
|
*namespaces* is an optional mapping from namespace prefix to full name.
|
|
|
|
Return list containing all matching elements in document order.
|
|
|
|
"""
|
|
# assert self._root is not None
|
|
if path[:1] == "/":
|
|
path = "." + path
|
|
warnings.warn(
|
|
"This search is broken in 1.3 and earlier, and will be "
|
|
"fixed in a future version. If you rely on the current "
|
|
"behaviour, change it to %r" % path,
|
|
FutureWarning, stacklevel=2
|
|
)
|
|
return self._root.findall(path, namespaces)
|
|
|
|
def iterfind(self, path, namespaces=None):
|
|
"""Find all matching subelements by tag name or path.
|
|
|
|
Same as getroot().iterfind(path), which is element.iterfind()
|
|
|
|
*path* is a string having either an element tag or an XPath,
|
|
*namespaces* is an optional mapping from namespace prefix to full name.
|
|
|
|
Return an iterable yielding all matching elements in document order.
|
|
|
|
"""
|
|
# assert self._root is not None
|
|
if path[:1] == "/":
|
|
path = "." + path
|
|
warnings.warn(
|
|
"This search is broken in 1.3 and earlier, and will be "
|
|
"fixed in a future version. If you rely on the current "
|
|
"behaviour, change it to %r" % path,
|
|
FutureWarning, stacklevel=2
|
|
)
|
|
return self._root.iterfind(path, namespaces)
|
|
|
|
def write(self, file_or_filename,
|
|
encoding=None,
|
|
xml_declaration=None,
|
|
default_namespace=None,
|
|
method=None, *,
|
|
short_empty_elements=True):
|
|
"""Write element tree to a file as XML.
|
|
|
|
Arguments:
|
|
*file_or_filename* -- file name or a file object opened for writing
|
|
|
|
*encoding* -- the output encoding (default: US-ASCII)
|
|
|
|
*xml_declaration* -- bool indicating if an XML declaration should be
|
|
added to the output. If None, an XML declaration
|
|
is added if encoding IS NOT either of:
|
|
US-ASCII, UTF-8, or Unicode
|
|
|
|
*default_namespace* -- sets the default XML namespace (for "xmlns")
|
|
|
|
*method* -- either "xml" (default), "html, "text", or "c14n"
|
|
|
|
*short_empty_elements* -- controls the formatting of elements
|
|
that contain no content. If True (default)
|
|
they are emitted as a single self-closed
|
|
tag, otherwise they are emitted as a pair
|
|
of start/end tags
|
|
|
|
"""
|
|
if not method:
|
|
method = "xml"
|
|
elif method not in _serialize:
|
|
raise ValueError("unknown method %r" % method)
|
|
if not encoding:
|
|
if method == "c14n":
|
|
encoding = "utf-8"
|
|
else:
|
|
encoding = "us-ascii"
|
|
enc_lower = encoding.lower()
|
|
with _get_writer(file_or_filename, enc_lower) as write:
|
|
if method == "xml" and (xml_declaration or
|
|
(xml_declaration is None and
|
|
enc_lower not in ("utf-8", "us-ascii", "unicode"))):
|
|
declared_encoding = encoding
|
|
if enc_lower == "unicode":
|
|
# Retrieve the default encoding for the xml declaration
|
|
import locale
|
|
declared_encoding = locale.getpreferredencoding()
|
|
write("<?xml version='1.0' encoding='%s'?>\n" % (
|
|
declared_encoding,))
|
|
if method == "text":
|
|
_serialize_text(write, self._root)
|
|
else:
|
|
qnames, namespaces = _namespaces(self._root, default_namespace)
|
|
serialize = _serialize[method]
|
|
serialize(write, self._root, qnames, namespaces,
|
|
short_empty_elements=short_empty_elements)
|
|
|
|
def write_c14n(self, file):
|
|
# lxml.etree compatibility. use output method instead
|
|
return self.write(file, method="c14n")
|
|
|
|
# --------------------------------------------------------------------
|
|
# serialization support
|
|
|
|
@contextlib.contextmanager
|
|
def _get_writer(file_or_filename, encoding):
|
|
# returns text write method and release all resources after using
|
|
try:
|
|
write = file_or_filename.write
|
|
except AttributeError:
|
|
# file_or_filename is a file name
|
|
if encoding == "unicode":
|
|
file = open(file_or_filename, "w")
|
|
else:
|
|
file = open(file_or_filename, "w", encoding=encoding,
|
|
errors="xmlcharrefreplace")
|
|
with file:
|
|
yield file.write
|
|
else:
|
|
# file_or_filename is a file-like object
|
|
# encoding determines if it is a text or binary writer
|
|
if encoding == "unicode":
|
|
# use a text writer as is
|
|
yield write
|
|
else:
|
|
# wrap a binary writer with TextIOWrapper
|
|
with contextlib.ExitStack() as stack:
|
|
if isinstance(file_or_filename, io.BufferedIOBase):
|
|
file = file_or_filename
|
|
elif isinstance(file_or_filename, io.RawIOBase):
|
|
file = io.BufferedWriter(file_or_filename)
|
|
# Keep the original file open when the BufferedWriter is
|
|
# destroyed
|
|
stack.callback(file.detach)
|
|
else:
|
|
# This is to handle passed objects that aren't in the
|
|
# IOBase hierarchy, but just have a write method
|
|
file = io.BufferedIOBase()
|
|
file.writable = lambda: True
|
|
file.write = write
|
|
try:
|
|
# TextIOWrapper uses this methods to determine
|
|
# if BOM (for UTF-16, etc) should be added
|
|
file.seekable = file_or_filename.seekable
|
|
file.tell = file_or_filename.tell
|
|
except AttributeError:
|
|
pass
|
|
file = io.TextIOWrapper(file,
|
|
encoding=encoding,
|
|
errors="xmlcharrefreplace",
|
|
newline="\n")
|
|
# Keep the original file open when the TextIOWrapper is
|
|
# destroyed
|
|
stack.callback(file.detach)
|
|
yield file.write
|
|
|
|
def _namespaces(elem, default_namespace=None):
|
|
# identify namespaces used in this tree
|
|
|
|
# maps qnames to *encoded* prefix:local names
|
|
qnames = {None: None}
|
|
|
|
# maps uri:s to prefixes
|
|
namespaces = {}
|
|
if default_namespace:
|
|
namespaces[default_namespace] = ""
|
|
|
|
def add_qname(qname):
|
|
# calculate serialized qname representation
|
|
try:
|
|
if qname[:1] == "{":
|
|
uri, tag = qname[1:].rsplit("}", 1)
|
|
prefix = namespaces.get(uri)
|
|
if prefix is None:
|
|
prefix = _namespace_map.get(uri)
|
|
if prefix is None:
|
|
prefix = "ns%d" % len(namespaces)
|
|
if prefix != "xml":
|
|
namespaces[uri] = prefix
|
|
if prefix:
|
|
qnames[qname] = "%s:%s" % (prefix, tag)
|
|
else:
|
|
qnames[qname] = tag # default element
|
|
else:
|
|
if default_namespace:
|
|
# FIXME: can this be handled in XML 1.0?
|
|
raise ValueError(
|
|
"cannot use non-qualified names with "
|
|
"default_namespace option"
|
|
)
|
|
qnames[qname] = qname
|
|
except TypeError:
|
|
_raise_serialization_error(qname)
|
|
|
|
# populate qname and namespaces table
|
|
for elem in elem.iter():
|
|
tag = elem.tag
|
|
if isinstance(tag, QName):
|
|
if tag.text not in qnames:
|
|
add_qname(tag.text)
|
|
elif isinstance(tag, str):
|
|
if tag not in qnames:
|
|
add_qname(tag)
|
|
elif tag is not None and tag is not Comment and tag is not PI:
|
|
_raise_serialization_error(tag)
|
|
for key, value in elem.items():
|
|
if isinstance(key, QName):
|
|
key = key.text
|
|
if key not in qnames:
|
|
add_qname(key)
|
|
if isinstance(value, QName) and value.text not in qnames:
|
|
add_qname(value.text)
|
|
text = elem.text
|
|
if isinstance(text, QName) and text.text not in qnames:
|
|
add_qname(text.text)
|
|
return qnames, namespaces
|
|
|
|
def _serialize_xml(write, elem, qnames, namespaces,
|
|
short_empty_elements, **kwargs):
|
|
tag = elem.tag
|
|
text = elem.text
|
|
if tag is Comment:
|
|
write("<!--%s-->" % text)
|
|
elif tag is ProcessingInstruction:
|
|
write("<?%s?>" % text)
|
|
else:
|
|
tag = qnames[tag]
|
|
if tag is None:
|
|
if text:
|
|
write(_escape_cdata(text))
|
|
for e in elem:
|
|
_serialize_xml(write, e, qnames, None,
|
|
short_empty_elements=short_empty_elements)
|
|
else:
|
|
write("<" + tag)
|
|
items = list(elem.items())
|
|
if items or namespaces:
|
|
if namespaces:
|
|
for v, k in sorted(namespaces.items(),
|
|
key=lambda x: x[1]): # sort on prefix
|
|
if k:
|
|
k = ":" + k
|
|
write(" xmlns%s=\"%s\"" % (
|
|
k,
|
|
_escape_attrib(v)
|
|
))
|
|
for k, v in sorted(items): # lexical order
|
|
if isinstance(k, QName):
|
|
k = k.text
|
|
if isinstance(v, QName):
|
|
v = qnames[v.text]
|
|
else:
|
|
v = _escape_attrib(v)
|
|
write(" %s=\"%s\"" % (qnames[k], v))
|
|
if text or len(elem) or not short_empty_elements:
|
|
write(">")
|
|
if text:
|
|
write(_escape_cdata(text))
|
|
for e in elem:
|
|
_serialize_xml(write, e, qnames, None,
|
|
short_empty_elements=short_empty_elements)
|
|
write("</" + tag + ">")
|
|
else:
|
|
write(" />")
|
|
if elem.tail:
|
|
write(_escape_cdata(elem.tail))
|
|
|
|
HTML_EMPTY = ("area", "base", "basefont", "br", "col", "frame", "hr",
|
|
"img", "input", "isindex", "link", "meta", "param")
|
|
|
|
try:
|
|
HTML_EMPTY = set(HTML_EMPTY)
|
|
except NameError:
|
|
pass
|
|
|
|
def _serialize_html(write, elem, qnames, namespaces, **kwargs):
|
|
tag = elem.tag
|
|
text = elem.text
|
|
if tag is Comment:
|
|
write("<!--%s-->" % _escape_cdata(text))
|
|
elif tag is ProcessingInstruction:
|
|
write("<?%s?>" % _escape_cdata(text))
|
|
else:
|
|
tag = qnames[tag]
|
|
if tag is None:
|
|
if text:
|
|
write(_escape_cdata(text))
|
|
for e in elem:
|
|
_serialize_html(write, e, qnames, None)
|
|
else:
|
|
write("<" + tag)
|
|
items = list(elem.items())
|
|
if items or namespaces:
|
|
if namespaces:
|
|
for v, k in sorted(namespaces.items(),
|
|
key=lambda x: x[1]): # sort on prefix
|
|
if k:
|
|
k = ":" + k
|
|
write(" xmlns%s=\"%s\"" % (
|
|
k,
|
|
_escape_attrib(v)
|
|
))
|
|
for k, v in sorted(items): # lexical order
|
|
if isinstance(k, QName):
|
|
k = k.text
|
|
if isinstance(v, QName):
|
|
v = qnames[v.text]
|
|
else:
|
|
v = _escape_attrib_html(v)
|
|
# FIXME: handle boolean attributes
|
|
write(" %s=\"%s\"" % (qnames[k], v))
|
|
write(">")
|
|
ltag = tag.lower()
|
|
if text:
|
|
if ltag == "script" or ltag == "style":
|
|
write(text)
|
|
else:
|
|
write(_escape_cdata(text))
|
|
for e in elem:
|
|
_serialize_html(write, e, qnames, None)
|
|
if ltag not in HTML_EMPTY:
|
|
write("</" + tag + ">")
|
|
if elem.tail:
|
|
write(_escape_cdata(elem.tail))
|
|
|
|
def _serialize_text(write, elem):
|
|
for part in elem.itertext():
|
|
write(part)
|
|
if elem.tail:
|
|
write(elem.tail)
|
|
|
|
_serialize = {
|
|
"xml": _serialize_xml,
|
|
"html": _serialize_html,
|
|
"text": _serialize_text,
|
|
# this optional method is imported at the end of the module
|
|
# "c14n": _serialize_c14n,
|
|
}
|
|
|
|
|
|
def register_namespace(prefix, uri):
|
|
"""Register a namespace prefix.
|
|
|
|
The registry is global, and any existing mapping for either the
|
|
given prefix or the namespace URI will be removed.
|
|
|
|
*prefix* is the namespace prefix, *uri* is a namespace uri. Tags and
|
|
attributes in this namespace will be serialized with prefix if possible.
|
|
|
|
ValueError is raised if prefix is reserved or is invalid.
|
|
|
|
"""
|
|
if re.match(r"ns\d+$", prefix):
|
|
raise ValueError("Prefix format reserved for internal use")
|
|
for k, v in list(_namespace_map.items()):
|
|
if k == uri or v == prefix:
|
|
del _namespace_map[k]
|
|
_namespace_map[uri] = prefix
|
|
|
|
_namespace_map = {
|
|
# "well-known" namespace prefixes
|
|
"http://www.w3.org/XML/1998/namespace": "xml",
|
|
"http://www.w3.org/1999/xhtml": "html",
|
|
"http://www.w3.org/1999/02/22-rdf-syntax-ns#": "rdf",
|
|
"http://schemas.xmlsoap.org/wsdl/": "wsdl",
|
|
# xml schema
|
|
"http://www.w3.org/2001/XMLSchema": "xs",
|
|
"http://www.w3.org/2001/XMLSchema-instance": "xsi",
|
|
# dublin core
|
|
"http://purl.org/dc/elements/1.1/": "dc",
|
|
}
|
|
# For tests and troubleshooting
|
|
register_namespace._namespace_map = _namespace_map
|
|
|
|
def _raise_serialization_error(text):
|
|
raise TypeError(
|
|
"cannot serialize %r (type %s)" % (text, type(text).__name__)
|
|
)
|
|
|
|
def _escape_cdata(text):
|
|
# escape character data
|
|
try:
|
|
# it's worth avoiding do-nothing calls for strings that are
|
|
# shorter than 500 character, or so. assume that's, by far,
|
|
# the most common case in most applications.
|
|
if "&" in text:
|
|
text = text.replace("&", "&")
|
|
if "<" in text:
|
|
text = text.replace("<", "<")
|
|
if ">" in text:
|
|
text = text.replace(">", ">")
|
|
return text
|
|
except (TypeError, AttributeError):
|
|
_raise_serialization_error(text)
|
|
|
|
def _escape_attrib(text):
|
|
# escape attribute value
|
|
try:
|
|
if "&" in text:
|
|
text = text.replace("&", "&")
|
|
if "<" in text:
|
|
text = text.replace("<", "<")
|
|
if ">" in text:
|
|
text = text.replace(">", ">")
|
|
if "\"" in text:
|
|
text = text.replace("\"", """)
|
|
if "\n" in text:
|
|
text = text.replace("\n", " ")
|
|
return text
|
|
except (TypeError, AttributeError):
|
|
_raise_serialization_error(text)
|
|
|
|
def _escape_attrib_html(text):
|
|
# escape attribute value
|
|
try:
|
|
if "&" in text:
|
|
text = text.replace("&", "&")
|
|
if ">" in text:
|
|
text = text.replace(">", ">")
|
|
if "\"" in text:
|
|
text = text.replace("\"", """)
|
|
return text
|
|
except (TypeError, AttributeError):
|
|
_raise_serialization_error(text)
|
|
|
|
# --------------------------------------------------------------------
|
|
|
|
def tostring(element, encoding=None, method=None, *,
|
|
short_empty_elements=True):
|
|
"""Generate string representation of XML element.
|
|
|
|
All subelements are included. If encoding is "unicode", a string
|
|
is returned. Otherwise a bytestring is returned.
|
|
|
|
*element* is an Element instance, *encoding* is an optional output
|
|
encoding defaulting to US-ASCII, *method* is an optional output which can
|
|
be one of "xml" (default), "html", "text" or "c14n".
|
|
|
|
Returns an (optionally) encoded string containing the XML data.
|
|
|
|
"""
|
|
stream = io.StringIO() if encoding == 'unicode' else io.BytesIO()
|
|
ElementTree(element).write(stream, encoding, method=method,
|
|
short_empty_elements=short_empty_elements)
|
|
return stream.getvalue()
|
|
|
|
class _ListDataStream(io.BufferedIOBase):
|
|
"""An auxiliary stream accumulating into a list reference."""
|
|
def __init__(self, lst):
|
|
self.lst = lst
|
|
|
|
def writable(self):
|
|
return True
|
|
|
|
def seekable(self):
|
|
return True
|
|
|
|
def write(self, b):
|
|
self.lst.append(b)
|
|
|
|
def tell(self):
|
|
return len(self.lst)
|
|
|
|
def tostringlist(element, encoding=None, method=None, *,
|
|
short_empty_elements=True):
|
|
lst = []
|
|
stream = _ListDataStream(lst)
|
|
ElementTree(element).write(stream, encoding, method=method,
|
|
short_empty_elements=short_empty_elements)
|
|
return lst
|
|
|
|
|
|
def dump(elem):
|
|
"""Write element tree or element structure to sys.stdout.
|
|
|
|
This function should be used for debugging only.
|
|
|
|
*elem* is either an ElementTree, or a single Element. The exact output
|
|
format is implementation dependent. In this version, it's written as an
|
|
ordinary XML file.
|
|
|
|
"""
|
|
# debugging
|
|
if not isinstance(elem, ElementTree):
|
|
elem = ElementTree(elem)
|
|
elem.write(sys.stdout, encoding="unicode")
|
|
tail = elem.getroot().tail
|
|
if not tail or tail[-1] != "\n":
|
|
sys.stdout.write("\n")
|
|
|
|
# --------------------------------------------------------------------
|
|
# parsing
|
|
|
|
|
|
def parse(source, parser=None):
|
|
"""Parse XML document into element tree.
|
|
|
|
*source* is a filename or file object containing XML data,
|
|
*parser* is an optional parser instance defaulting to XMLParser.
|
|
|
|
Return an ElementTree instance.
|
|
|
|
"""
|
|
tree = ElementTree()
|
|
tree.parse(source, parser)
|
|
return tree
|
|
|
|
|
|
def iterparse(source, events=None, parser=None):
|
|
"""Incrementally parse XML document into ElementTree.
|
|
|
|
This class also reports what's going on to the user based on the
|
|
*events* it is initialized with. The supported events are the strings
|
|
"start", "end", "start-ns" and "end-ns" (the "ns" events are used to get
|
|
detailed namespace information). If *events* is omitted, only
|
|
"end" events are reported.
|
|
|
|
*source* is a filename or file object containing XML data, *events* is
|
|
a list of events to report back, *parser* is an optional parser instance.
|
|
|
|
Returns an iterator providing (event, elem) pairs.
|
|
|
|
"""
|
|
# Use the internal, undocumented _parser argument for now; When the
|
|
# parser argument of iterparse is removed, this can be killed.
|
|
pullparser = XMLPullParser(events=events, _parser=parser)
|
|
def iterator():
|
|
try:
|
|
while True:
|
|
yield from pullparser.read_events()
|
|
# load event buffer
|
|
data = source.read(16 * 1024)
|
|
if not data:
|
|
break
|
|
pullparser.feed(data)
|
|
root = pullparser._close_and_return_root()
|
|
yield from pullparser.read_events()
|
|
it.root = root
|
|
finally:
|
|
if close_source:
|
|
source.close()
|
|
|
|
class IterParseIterator(collections.Iterator):
|
|
__next__ = iterator().__next__
|
|
it = IterParseIterator()
|
|
it.root = None
|
|
del iterator, IterParseIterator
|
|
|
|
close_source = False
|
|
if not hasattr(source, "read"):
|
|
source = open(source, "rb")
|
|
close_source = True
|
|
|
|
return it
|
|
|
|
|
|
class XMLPullParser:
|
|
|
|
def __init__(self, events=None, *, _parser=None):
|
|
# The _parser argument is for internal use only and must not be relied
|
|
# upon in user code. It will be removed in a future release.
|
|
# See http://bugs.python.org/issue17741 for more details.
|
|
|
|
self._events_queue = collections.deque()
|
|
self._parser = _parser or XMLParser(target=TreeBuilder())
|
|
# wire up the parser for event reporting
|
|
if events is None:
|
|
events = ("end",)
|
|
self._parser._setevents(self._events_queue, events)
|
|
|
|
def feed(self, data):
|
|
"""Feed encoded data to parser."""
|
|
if self._parser is None:
|
|
raise ValueError("feed() called after end of stream")
|
|
if data:
|
|
try:
|
|
self._parser.feed(data)
|
|
except SyntaxError as exc:
|
|
self._events_queue.append(exc)
|
|
|
|
def _close_and_return_root(self):
|
|
# iterparse needs this to set its root attribute properly :(
|
|
root = self._parser.close()
|
|
self._parser = None
|
|
return root
|
|
|
|
def close(self):
|
|
"""Finish feeding data to parser.
|
|
|
|
Unlike XMLParser, does not return the root element. Use
|
|
read_events() to consume elements from XMLPullParser.
|
|
"""
|
|
self._close_and_return_root()
|
|
|
|
def read_events(self):
|
|
"""Return an iterator over currently available (event, elem) pairs.
|
|
|
|
Events are consumed from the internal event queue as they are
|
|
retrieved from the iterator.
|
|
"""
|
|
events = self._events_queue
|
|
while events:
|
|
event = events.popleft()
|
|
if isinstance(event, Exception):
|
|
raise event
|
|
else:
|
|
yield event
|
|
|
|
|
|
def XML(text, parser=None):
|
|
"""Parse XML document from string constant.
|
|
|
|
This function can be used to embed "XML Literals" in Python code.
|
|
|
|
*text* is a string containing XML data, *parser* is an
|
|
optional parser instance, defaulting to the standard XMLParser.
|
|
|
|
Returns an Element instance.
|
|
|
|
"""
|
|
if not parser:
|
|
parser = XMLParser(target=TreeBuilder())
|
|
parser.feed(text)
|
|
return parser.close()
|
|
|
|
|
|
def XMLID(text, parser=None):
|
|
"""Parse XML document from string constant for its IDs.
|
|
|
|
*text* is a string containing XML data, *parser* is an
|
|
optional parser instance, defaulting to the standard XMLParser.
|
|
|
|
Returns an (Element, dict) tuple, in which the
|
|
dict maps element id:s to elements.
|
|
|
|
"""
|
|
if not parser:
|
|
parser = XMLParser(target=TreeBuilder())
|
|
parser.feed(text)
|
|
tree = parser.close()
|
|
ids = {}
|
|
for elem in tree.iter():
|
|
id = elem.get("id")
|
|
if id:
|
|
ids[id] = elem
|
|
return tree, ids
|
|
|
|
# Parse XML document from string constant. Alias for XML().
|
|
fromstring = XML
|
|
|
|
def fromstringlist(sequence, parser=None):
|
|
"""Parse XML document from sequence of string fragments.
|
|
|
|
*sequence* is a list of other sequence, *parser* is an optional parser
|
|
instance, defaulting to the standard XMLParser.
|
|
|
|
Returns an Element instance.
|
|
|
|
"""
|
|
if not parser:
|
|
parser = XMLParser(target=TreeBuilder())
|
|
for text in sequence:
|
|
parser.feed(text)
|
|
return parser.close()
|
|
|
|
# --------------------------------------------------------------------
|
|
|
|
|
|
class TreeBuilder:
|
|
"""Generic element structure builder.
|
|
|
|
This builder converts a sequence of start, data, and end method
|
|
calls to a well-formed element structure.
|
|
|
|
You can use this class to build an element structure using a custom XML
|
|
parser, or a parser for some other XML-like format.
|
|
|
|
*element_factory* is an optional element factory which is called
|
|
to create new Element instances, as necessary.
|
|
|
|
"""
|
|
def __init__(self, element_factory=None):
|
|
self._data = [] # data collector
|
|
self._elem = [] # element stack
|
|
self._last = None # last element
|
|
self._tail = None # true if we're after an end tag
|
|
if element_factory is None:
|
|
element_factory = Element
|
|
self._factory = element_factory
|
|
|
|
def close(self):
|
|
"""Flush builder buffers and return toplevel document Element."""
|
|
assert len(self._elem) == 0, "missing end tags"
|
|
assert self._last is not None, "missing toplevel element"
|
|
return self._last
|
|
|
|
def _flush(self):
|
|
if self._data:
|
|
if self._last is not None:
|
|
text = "".join(self._data)
|
|
if self._tail:
|
|
assert self._last.tail is None, "internal error (tail)"
|
|
self._last.tail = text
|
|
else:
|
|
assert self._last.text is None, "internal error (text)"
|
|
self._last.text = text
|
|
self._data = []
|
|
|
|
def data(self, data):
|
|
"""Add text to current element."""
|
|
self._data.append(data)
|
|
|
|
def start(self, tag, attrs):
|
|
"""Open new element and return it.
|
|
|
|
*tag* is the element name, *attrs* is a dict containing element
|
|
attributes.
|
|
|
|
"""
|
|
self._flush()
|
|
self._last = elem = self._factory(tag, attrs)
|
|
if self._elem:
|
|
self._elem[-1].append(elem)
|
|
self._elem.append(elem)
|
|
self._tail = 0
|
|
return elem
|
|
|
|
def end(self, tag):
|
|
"""Close and return current Element.
|
|
|
|
*tag* is the element name.
|
|
|
|
"""
|
|
self._flush()
|
|
self._last = self._elem.pop()
|
|
assert self._last.tag == tag,\
|
|
"end tag mismatch (expected %s, got %s)" % (
|
|
self._last.tag, tag)
|
|
self._tail = 1
|
|
return self._last
|
|
|
|
|
|
# also see ElementTree and TreeBuilder
|
|
class XMLParser:
|
|
"""Element structure builder for XML source data based on the expat parser.
|
|
|
|
*html* are predefined HTML entities (deprecated and not supported),
|
|
*target* is an optional target object which defaults to an instance of the
|
|
standard TreeBuilder class, *encoding* is an optional encoding string
|
|
which if given, overrides the encoding specified in the XML file:
|
|
http://www.iana.org/assignments/character-sets
|
|
|
|
"""
|
|
|
|
def __init__(self, html=0, target=None, encoding=None):
|
|
try:
|
|
from xml.parsers import expat
|
|
except ImportError:
|
|
try:
|
|
import pyexpat as expat
|
|
except ImportError:
|
|
raise ImportError(
|
|
"No module named expat; use SimpleXMLTreeBuilder instead"
|
|
)
|
|
parser = expat.ParserCreate(encoding, "}")
|
|
if target is None:
|
|
target = TreeBuilder()
|
|
# underscored names are provided for compatibility only
|
|
self.parser = self._parser = parser
|
|
self.target = self._target = target
|
|
self._error = expat.error
|
|
self._names = {} # name memo cache
|
|
# main callbacks
|
|
parser.DefaultHandlerExpand = self._default
|
|
if hasattr(target, 'start'):
|
|
parser.StartElementHandler = self._start
|
|
if hasattr(target, 'end'):
|
|
parser.EndElementHandler = self._end
|
|
if hasattr(target, 'data'):
|
|
parser.CharacterDataHandler = target.data
|
|
# miscellaneous callbacks
|
|
if hasattr(target, 'comment'):
|
|
parser.CommentHandler = target.comment
|
|
if hasattr(target, 'pi'):
|
|
parser.ProcessingInstructionHandler = target.pi
|
|
# Configure pyexpat: buffering, new-style attribute handling.
|
|
parser.buffer_text = 1
|
|
parser.ordered_attributes = 1
|
|
parser.specified_attributes = 1
|
|
self._doctype = None
|
|
self.entity = {}
|
|
try:
|
|
self.version = "Expat %d.%d.%d" % expat.version_info
|
|
except AttributeError:
|
|
pass # unknown
|
|
|
|
def _setevents(self, events_queue, events_to_report):
|
|
# Internal API for XMLPullParser
|
|
# events_to_report: a list of events to report during parsing (same as
|
|
# the *events* of XMLPullParser's constructor.
|
|
# events_queue: a list of actual parsing events that will be populated
|
|
# by the underlying parser.
|
|
#
|
|
parser = self._parser
|
|
append = events_queue.append
|
|
for event_name in events_to_report:
|
|
if event_name == "start":
|
|
parser.ordered_attributes = 1
|
|
parser.specified_attributes = 1
|
|
def handler(tag, attrib_in, event=event_name, append=append,
|
|
start=self._start):
|
|
append((event, start(tag, attrib_in)))
|
|
parser.StartElementHandler = handler
|
|
elif event_name == "end":
|
|
def handler(tag, event=event_name, append=append,
|
|
end=self._end):
|
|
append((event, end(tag)))
|
|
parser.EndElementHandler = handler
|
|
elif event_name == "start-ns":
|
|
def handler(prefix, uri, event=event_name, append=append):
|
|
append((event, (prefix or "", uri or "")))
|
|
parser.StartNamespaceDeclHandler = handler
|
|
elif event_name == "end-ns":
|
|
def handler(prefix, event=event_name, append=append):
|
|
append((event, None))
|
|
parser.EndNamespaceDeclHandler = handler
|
|
else:
|
|
raise ValueError("unknown event %r" % event_name)
|
|
|
|
def _raiseerror(self, value):
|
|
err = ParseError(value)
|
|
err.code = value.code
|
|
err.position = value.lineno, value.offset
|
|
raise err
|
|
|
|
def _fixname(self, key):
|
|
# expand qname, and convert name string to ascii, if possible
|
|
try:
|
|
name = self._names[key]
|
|
except KeyError:
|
|
name = key
|
|
if "}" in name:
|
|
name = "{" + name
|
|
self._names[key] = name
|
|
return name
|
|
|
|
def _start(self, tag, attr_list):
|
|
# Handler for expat's StartElementHandler. Since ordered_attributes
|
|
# is set, the attributes are reported as a list of alternating
|
|
# attribute name,value.
|
|
fixname = self._fixname
|
|
tag = fixname(tag)
|
|
attrib = {}
|
|
if attr_list:
|
|
for i in range(0, len(attr_list), 2):
|
|
attrib[fixname(attr_list[i])] = attr_list[i+1]
|
|
return self.target.start(tag, attrib)
|
|
|
|
def _end(self, tag):
|
|
return self.target.end(self._fixname(tag))
|
|
|
|
def _default(self, text):
|
|
prefix = text[:1]
|
|
if prefix == "&":
|
|
# deal with undefined entities
|
|
try:
|
|
data_handler = self.target.data
|
|
except AttributeError:
|
|
return
|
|
try:
|
|
data_handler(self.entity[text[1:-1]])
|
|
except KeyError:
|
|
from xml.parsers import expat
|
|
err = expat.error(
|
|
"undefined entity %s: line %d, column %d" %
|
|
(text, self.parser.ErrorLineNumber,
|
|
self.parser.ErrorColumnNumber)
|
|
)
|
|
err.code = 11 # XML_ERROR_UNDEFINED_ENTITY
|
|
err.lineno = self.parser.ErrorLineNumber
|
|
err.offset = self.parser.ErrorColumnNumber
|
|
raise err
|
|
elif prefix == "<" and text[:9] == "<!DOCTYPE":
|
|
self._doctype = [] # inside a doctype declaration
|
|
elif self._doctype is not None:
|
|
# parse doctype contents
|
|
if prefix == ">":
|
|
self._doctype = None
|
|
return
|
|
text = text.strip()
|
|
if not text:
|
|
return
|
|
self._doctype.append(text)
|
|
n = len(self._doctype)
|
|
if n > 2:
|
|
type = self._doctype[1]
|
|
if type == "PUBLIC" and n == 4:
|
|
name, type, pubid, system = self._doctype
|
|
if pubid:
|
|
pubid = pubid[1:-1]
|
|
elif type == "SYSTEM" and n == 3:
|
|
name, type, system = self._doctype
|
|
pubid = None
|
|
else:
|
|
return
|
|
if hasattr(self.target, "doctype"):
|
|
self.target.doctype(name, pubid, system[1:-1])
|
|
elif self.doctype != self._XMLParser__doctype:
|
|
# warn about deprecated call
|
|
self._XMLParser__doctype(name, pubid, system[1:-1])
|
|
self.doctype(name, pubid, system[1:-1])
|
|
self._doctype = None
|
|
|
|
def doctype(self, name, pubid, system):
|
|
"""(Deprecated) Handle doctype declaration
|
|
|
|
*name* is the Doctype name, *pubid* is the public identifier,
|
|
and *system* is the system identifier.
|
|
|
|
"""
|
|
warnings.warn(
|
|
"This method of XMLParser is deprecated. Define doctype() "
|
|
"method on the TreeBuilder target.",
|
|
DeprecationWarning,
|
|
)
|
|
|
|
# sentinel, if doctype is redefined in a subclass
|
|
__doctype = doctype
|
|
|
|
def feed(self, data):
|
|
"""Feed encoded data to parser."""
|
|
try:
|
|
self.parser.Parse(data, 0)
|
|
except self._error as v:
|
|
self._raiseerror(v)
|
|
|
|
def close(self):
|
|
"""Finish feeding data to parser and return element structure."""
|
|
try:
|
|
self.parser.Parse("", 1) # end of data
|
|
except self._error as v:
|
|
self._raiseerror(v)
|
|
try:
|
|
close_handler = self.target.close
|
|
except AttributeError:
|
|
pass
|
|
else:
|
|
return close_handler()
|
|
finally:
|
|
# get rid of circular references
|
|
del self.parser, self._parser
|
|
del self.target, self._target
|
|
|
|
|
|
# Import the C accelerators
|
|
try:
|
|
# Element is going to be shadowed by the C implementation. We need to keep
|
|
# the Python version of it accessible for some "creative" by external code
|
|
# (see tests)
|
|
_Element_Py = Element
|
|
|
|
# Element, SubElement, ParseError, TreeBuilder, XMLParser
|
|
from _elementtree import *
|
|
except ImportError:
|
|
pass
|