mirror of https://github.com/python/cpython
1781 lines
59 KiB
Python
1781 lines
59 KiB
Python
#
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# ElementTree
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# $Id: ElementTree.py 3440 2008-07-18 14:45:01Z fredrik $
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#
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# light-weight XML support for Python 2.3 and later.
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#
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# history (since 1.2.6):
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# 2005-11-12 fl added tostringlist/fromstringlist helpers
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# 2006-07-05 fl merged in selected changes from the 1.3 sandbox
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# 2006-07-05 fl removed support for 2.1 and earlier
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# 2007-06-21 fl added deprecation/future warnings
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# 2007-08-25 fl added doctype hook, added parser version attribute etc
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# 2007-08-26 fl added new serializer code (better namespace handling, etc)
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# 2007-08-27 fl warn for broken /tag searches on tree level
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# 2007-09-02 fl added html/text methods to serializer (experimental)
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# 2007-09-05 fl added method argument to tostring/tostringlist
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# 2007-09-06 fl improved error handling
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# 2007-09-13 fl added itertext, iterfind; assorted cleanups
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# 2007-12-15 fl added C14N hooks, copy method (experimental)
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#
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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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# --------------------------------------------------------------------
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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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# 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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__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", "XMLTreeBuilder",
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"register_namespace",
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]
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VERSION = "1.3.0"
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##
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# The <b>Element</b> type is a flexible container object, designed to
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# store hierarchical data structures in memory. The type can be
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# described as a cross between a list and a dictionary.
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# <p>
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# Each element has a number of properties associated with it:
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# <ul>
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# <li>a <i>tag</i>. This is a string identifying what kind of data
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# this element represents (the element type, in other words).</li>
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# <li>a number of <i>attributes</i>, stored in a Python dictionary.</li>
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# <li>a <i>text</i> string.</li>
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# <li>an optional <i>tail</i> string.</li>
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# <li>a number of <i>child elements</i>, stored in a Python sequence</li>
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# </ul>
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#
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# To create an element instance, use the {@link #Element} constructor
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# or the {@link #SubElement} factory function.
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# <p>
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# The {@link #ElementTree} class can be used to wrap an element
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# structure, and convert it from and to XML.
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##
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import sys
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import re
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import warnings
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class _SimpleElementPath:
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# emulate pre-1.2 find/findtext/findall behaviour
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def find(self, element, tag, namespaces=None):
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for elem in element:
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if elem.tag == tag:
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return elem
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return None
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def findtext(self, element, tag, default=None, namespaces=None):
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elem = self.find(element, tag)
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if elem is None:
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return default
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return elem.text or ""
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def iterfind(self, element, tag, namespaces=None):
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if tag[:3] == ".//":
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for elem in element.iter(tag[3:]):
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yield elem
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for elem in element:
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if elem.tag == tag:
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yield elem
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def findall(self, element, tag, namespaces=None):
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return list(self.iterfind(element, tag, namespaces))
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try:
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from . import ElementPath
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except ImportError:
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ElementPath = _SimpleElementPath()
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##
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# Parser error. This is a subclass of <b>SyntaxError</b>.
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# <p>
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# In addition to the exception value, an exception instance contains a
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# specific exception code in the <b>code</b> attribute, and the line and
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# column of the error in the <b>position</b> attribute.
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class ParseError(SyntaxError):
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pass
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# --------------------------------------------------------------------
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##
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# Checks if an object appears to be a valid element object.
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#
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# @param An element instance.
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# @return A true value if this is an element object.
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# @defreturn flag
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def iselement(element):
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# FIXME: not sure about this;
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# isinstance(element, Element) or look for tag/attrib/text attributes
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return hasattr(element, 'tag')
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##
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# Element class. This class defines the Element interface, and
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# provides a reference implementation of this interface.
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# <p>
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# The element name, attribute names, and attribute values can be
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# either ASCII strings (ordinary Python strings containing only 7-bit
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# ASCII characters) or Unicode strings.
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#
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# @param tag The element name.
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# @param attrib An optional dictionary, containing element attributes.
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# @param **extra Additional attributes, given as keyword arguments.
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# @see Element
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# @see SubElement
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# @see Comment
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# @see ProcessingInstruction
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class Element:
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# <tag attrib>text<child/>...</tag>tail
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##
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# (Attribute) Element tag.
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tag = None
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##
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# (Attribute) Element attribute dictionary. Where possible, use
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# {@link #Element.get},
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# {@link #Element.set},
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# {@link #Element.keys}, and
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# {@link #Element.items} to access
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# element attributes.
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attrib = None
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##
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# (Attribute) Text before first subelement. This is either a
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# string or the value None. Note that if there was no text, this
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# attribute may be either None or an empty string, depending on
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# the parser.
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text = None
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##
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# (Attribute) Text after this element's end tag, but before the
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# next sibling element's start tag. This is either a string or
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# the value None. Note that if there was no text, this attribute
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# may be either None or an empty string, depending on the parser.
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tail = None # text after end tag, if any
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# constructor
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def __init__(self, tag, attrib={}, **extra):
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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 "<Element %s at 0x%x>" % (repr(self.tag), id(self))
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##
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# Creates a new element object of the same type as this element.
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#
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# @param tag Element tag.
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# @param attrib Element attributes, given as a dictionary.
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# @return A new element instance.
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def makeelement(self, tag, attrib):
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return self.__class__(tag, attrib)
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##
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# (Experimental) Copies the current element. This creates a
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# shallow copy; subelements will be shared with the original tree.
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#
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# @return A new element instance.
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def copy(self):
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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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##
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# Returns the number of subelements. Note that this only counts
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# full elements; to check if there's any content in an element, you
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# have to check both the length and the <b>text</b> attribute.
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#
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# @return The number of subelements.
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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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##
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# Returns the given subelement, by index.
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#
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# @param index What subelement to return.
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# @return The given subelement.
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# @exception IndexError If the given element does not exist.
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def __getitem__(self, index):
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return self._children[index]
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##
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# Replaces the given subelement, by index.
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#
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# @param index What subelement to replace.
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# @param element The new element value.
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# @exception IndexError If the given element does not exist.
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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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##
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# Deletes the given subelement, by index.
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#
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# @param index What subelement to delete.
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# @exception IndexError If the given element does not exist.
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def __delitem__(self, index):
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del self._children[index]
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##
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# Adds a subelement to the end of this element. In document order,
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# the new element will appear after the last existing subelement (or
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# directly after the text, if it's the first subelement), but before
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# the end tag for this element.
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#
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# @param element The element to add.
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def append(self, element):
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self._assert_is_element(element)
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self._children.append(element)
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##
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# Appends subelements from a sequence.
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#
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# @param elements A sequence object with zero or more elements.
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# @since 1.3
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def extend(self, elements):
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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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##
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# Inserts a subelement at the given position in this element.
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#
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# @param index Where to insert the new subelement.
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def insert(self, index, element):
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self._assert_is_element(element)
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self._children.insert(index, element)
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def _assert_is_element(self, e):
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if not isinstance(e, Element):
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raise TypeError('expected an Element, not %s' % type(e).__name__)
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##
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# Removes a matching subelement. Unlike the <b>find</b> methods,
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# this method compares elements based on identity, not on tag
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# value or contents. To remove subelements by other means, the
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# easiest way is often to use a list comprehension to select what
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# elements to keep, and use slice assignment to update the parent
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# element.
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#
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# @param element What element to remove.
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# @exception ValueError If a matching element could not be found.
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def remove(self, element):
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# assert iselement(element)
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self._children.remove(element)
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##
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# (Deprecated) Returns all subelements. The elements are returned
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# in document order.
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#
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# @return A list of subelements.
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# @defreturn list of Element instances
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def getchildren(self):
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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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##
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# Finds the first matching subelement, by tag name or path.
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#
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# @param path What element to look for.
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# @keyparam namespaces Optional namespace prefix map.
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# @return The first matching element, or None if no element was found.
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# @defreturn Element or None
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def find(self, path, namespaces=None):
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return ElementPath.find(self, path, namespaces)
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##
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# Finds text for the first matching subelement, by tag name or path.
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#
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# @param path What element to look for.
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# @param default What to return if the element was not found.
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# @keyparam namespaces Optional namespace prefix map.
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# @return The text content of the first matching element, or the
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# default value no element was found. Note that if the element
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# is found, but has no text content, this method returns an
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# empty string.
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# @defreturn string
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def findtext(self, path, default=None, namespaces=None):
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return ElementPath.findtext(self, path, default, namespaces)
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##
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# Finds all matching subelements, by tag name or path.
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#
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# @param path What element to look for.
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# @keyparam namespaces Optional namespace prefix map.
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# @return A list or other sequence containing all matching elements,
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# in document order.
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# @defreturn list of Element instances
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def findall(self, path, namespaces=None):
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return ElementPath.findall(self, path, namespaces)
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##
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# Finds all matching subelements, by tag name or path.
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#
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# @param path What element to look for.
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# @keyparam namespaces Optional namespace prefix map.
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# @return An iterator or sequence containing all matching elements,
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# in document order.
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# @defreturn a generated sequence of Element instances
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def iterfind(self, path, namespaces=None):
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return ElementPath.iterfind(self, path, namespaces)
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##
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# Resets an element. This function removes all subelements, clears
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# all attributes, and sets the <b>text</b> and <b>tail</b> attributes
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# to None.
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def clear(self):
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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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##
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# Gets an element attribute. Equivalent to <b>attrib.get</b>, but
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# some implementations may handle this a bit more efficiently.
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#
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# @param key What attribute to look for.
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# @param default What to return if the attribute was not found.
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# @return The attribute value, or the default value, if the
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# attribute was not found.
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# @defreturn string or None
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def get(self, key, default=None):
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return self.attrib.get(key, default)
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##
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# Sets an element attribute. Equivalent to <b>attrib[key] = value</b>,
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# but some implementations may handle this a bit more efficiently.
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#
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# @param key What attribute to set.
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# @param value The attribute value.
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def set(self, key, value):
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self.attrib[key] = value
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##
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# Gets a list of attribute names. The names are returned in an
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# arbitrary order (just like for an ordinary Python dictionary).
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# Equivalent to <b>attrib.keys()</b>.
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#
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# @return A list of element attribute names.
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# @defreturn list of strings
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def keys(self):
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return self.attrib.keys()
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##
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# Gets element attributes, as a sequence. The attributes are
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# returned in an arbitrary order. Equivalent to <b>attrib.items()</b>.
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#
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# @return A list of (name, value) tuples for all attributes.
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# @defreturn list of (string, string) tuples
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def items(self):
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return self.attrib.items()
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##
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# Creates a tree iterator. The iterator loops over this element
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# and all subelements, in document order, and returns all elements
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# with a matching tag.
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# <p>
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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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#
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# @param tag 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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# @defreturn iterator
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|
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def iter(self, tag=None):
|
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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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for e in e.iter(tag):
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yield e
|
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|
|
# compatibility
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|
def getiterator(self, tag=None):
|
|
# Change for a DeprecationWarning in 1.4
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warnings.warn(
|
|
"This method will be removed in future versions. "
|
|
"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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|
|
##
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# Creates a text iterator. The iterator loops over this element
|
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# and all subelements, in document order, and returns all inner
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# text.
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#
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# @return An iterator containing all inner text.
|
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# @defreturn iterator
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|
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|
def itertext(self):
|
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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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if self.text:
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yield self.text
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for e in self:
|
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for s in e.itertext():
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yield s
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if e.tail:
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yield e.tail
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|
|
# compatibility
|
|
_Element = _ElementInterface = Element
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|
|
|
##
|
|
# Subelement factory. This function creates an element instance, and
|
|
# appends it to an existing element.
|
|
# <p>
|
|
# The element name, attribute names, and attribute values can be
|
|
# either 8-bit ASCII strings or Unicode strings.
|
|
#
|
|
# @param parent The parent element.
|
|
# @param tag The subelement name.
|
|
# @param attrib An optional dictionary, containing element attributes.
|
|
# @param **extra Additional attributes, given as keyword arguments.
|
|
# @return An element instance.
|
|
# @defreturn Element
|
|
|
|
def SubElement(parent, tag, attrib={}, **extra):
|
|
attrib = attrib.copy()
|
|
attrib.update(extra)
|
|
element = parent.makeelement(tag, attrib)
|
|
parent.append(element)
|
|
return element
|
|
|
|
##
|
|
# Comment element factory. This factory function creates a special
|
|
# element that will be serialized as an XML comment by the standard
|
|
# serializer.
|
|
# <p>
|
|
# The comment string can be either an 8-bit ASCII string or a Unicode
|
|
# string.
|
|
#
|
|
# @param text A string containing the comment string.
|
|
# @return An element instance, representing a comment.
|
|
# @defreturn Element
|
|
|
|
def Comment(text=None):
|
|
element = Element(Comment)
|
|
element.text = text
|
|
return element
|
|
|
|
##
|
|
# PI element factory. This factory function creates a special element
|
|
# that will be serialized as an XML processing instruction by the standard
|
|
# serializer.
|
|
#
|
|
# @param target A string containing the PI target.
|
|
# @param text A string containing the PI contents, if any.
|
|
# @return An element instance, representing a PI.
|
|
# @defreturn Element
|
|
|
|
def ProcessingInstruction(target, text=None):
|
|
element = Element(ProcessingInstruction)
|
|
element.text = target
|
|
if text:
|
|
element.text = element.text + " " + text
|
|
return element
|
|
|
|
PI = ProcessingInstruction
|
|
|
|
##
|
|
# QName wrapper. This can be used to wrap a QName attribute value, in
|
|
# order to get proper namespace handling on output.
|
|
#
|
|
# @param text A string containing the QName value, in the form {uri}local,
|
|
# or, if the tag argument is given, the URI part of a QName.
|
|
# @param tag Optional tag. If given, the first argument is interpreted as
|
|
# an URI, and this argument is interpreted as a local name.
|
|
# @return An opaque object, representing the QName.
|
|
|
|
class QName:
|
|
def __init__(self, text_or_uri, tag=None):
|
|
if tag:
|
|
text_or_uri = "{%s}%s" % (text_or_uri, tag)
|
|
self.text = text_or_uri
|
|
def __str__(self):
|
|
return self.text
|
|
def __repr__(self):
|
|
return '<QName %r>' % (self.text,)
|
|
def __hash__(self):
|
|
return hash(self.text)
|
|
def __le__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text <= other.text
|
|
return self.text <= other
|
|
def __lt__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text < other.text
|
|
return self.text < other
|
|
def __ge__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text >= other.text
|
|
return self.text >= other
|
|
def __gt__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text > other.text
|
|
return self.text > other
|
|
def __eq__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text == other.text
|
|
return self.text == other
|
|
def __ne__(self, other):
|
|
if isinstance(other, QName):
|
|
return self.text != other.text
|
|
return self.text != other
|
|
|
|
# --------------------------------------------------------------------
|
|
|
|
##
|
|
# ElementTree wrapper class. This class represents an entire element
|
|
# hierarchy, and adds some extra support for serialization to and from
|
|
# standard XML.
|
|
#
|
|
# @param element Optional root element.
|
|
# @keyparam file Optional file handle or file name. If given, the
|
|
# tree is initialized with the contents of this XML file.
|
|
|
|
class ElementTree:
|
|
|
|
def __init__(self, element=None, file=None):
|
|
# assert element is None or iselement(element)
|
|
self._root = element # first node
|
|
if file:
|
|
self.parse(file)
|
|
|
|
##
|
|
# Gets the root element for this tree.
|
|
#
|
|
# @return An element instance.
|
|
# @defreturn Element
|
|
|
|
def getroot(self):
|
|
return self._root
|
|
|
|
##
|
|
# Replaces the root element for this tree. This discards the
|
|
# current contents of the tree, and replaces it with the given
|
|
# element. Use with care.
|
|
#
|
|
# @param element An element instance.
|
|
|
|
def _setroot(self, element):
|
|
# assert iselement(element)
|
|
self._root = element
|
|
|
|
##
|
|
# Loads an external XML document into this element tree.
|
|
#
|
|
# @param source A file name or file object. If a file object is
|
|
# given, it only has to implement a <b>read(n)</b> method.
|
|
# @keyparam parser An optional parser instance. If not given, the
|
|
# standard {@link XMLParser} parser is used.
|
|
# @return The document root element.
|
|
# @defreturn Element
|
|
# @exception ParseError If the parser fails to parse the document.
|
|
|
|
def parse(self, source, parser=None):
|
|
close_source = False
|
|
if not hasattr(source, "read"):
|
|
source = open(source, "rb")
|
|
close_source = True
|
|
try:
|
|
if not parser:
|
|
parser = XMLParser(target=TreeBuilder())
|
|
while 1:
|
|
data = source.read(65536)
|
|
if not data:
|
|
break
|
|
parser.feed(data)
|
|
self._root = parser.close()
|
|
return self._root
|
|
finally:
|
|
if close_source:
|
|
source.close()
|
|
|
|
##
|
|
# Creates a tree iterator for the root element. The iterator loops
|
|
# over all elements in this tree, in document order.
|
|
#
|
|
# @param tag What tags to look for (default is to return all elements)
|
|
# @return An iterator.
|
|
# @defreturn iterator
|
|
|
|
def iter(self, tag=None):
|
|
# 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))
|
|
|
|
##
|
|
# Finds the first toplevel element with given tag.
|
|
# Same as getroot().find(path).
|
|
#
|
|
# @param path What element to look for.
|
|
# @keyparam namespaces Optional namespace prefix map.
|
|
# @return The first matching element, or None if no element was found.
|
|
# @defreturn Element or None
|
|
|
|
def find(self, path, namespaces=None):
|
|
# 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)
|
|
|
|
##
|
|
# Finds the element text for the first toplevel element with given
|
|
# tag. Same as getroot().findtext(path).
|
|
#
|
|
# @param path What toplevel element to look for.
|
|
# @param default What to return if the element was not found.
|
|
# @keyparam namespaces Optional namespace prefix map.
|
|
# @return The text content of the first matching element, or the
|
|
# default value no element was found. Note that if the element
|
|
# is found, but has no text content, this method returns an
|
|
# empty string.
|
|
# @defreturn string
|
|
|
|
def findtext(self, path, default=None, namespaces=None):
|
|
# 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)
|
|
|
|
##
|
|
# Finds all toplevel elements with the given tag.
|
|
# Same as getroot().findall(path).
|
|
#
|
|
# @param path What element to look for.
|
|
# @keyparam namespaces Optional namespace prefix map.
|
|
# @return A list or iterator containing all matching elements,
|
|
# in document order.
|
|
# @defreturn list of Element instances
|
|
|
|
def findall(self, path, namespaces=None):
|
|
# 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)
|
|
|
|
##
|
|
# Finds all matching subelements, by tag name or path.
|
|
# Same as getroot().iterfind(path).
|
|
#
|
|
# @param path What element to look for.
|
|
# @keyparam namespaces Optional namespace prefix map.
|
|
# @return An iterator or sequence containing all matching elements,
|
|
# in document order.
|
|
# @defreturn a generated sequence of Element instances
|
|
|
|
def iterfind(self, path, namespaces=None):
|
|
# 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)
|
|
|
|
##
|
|
# Writes the element tree to a file, as XML.
|
|
#
|
|
# @def write(file, **options)
|
|
# @param file A file name, or a file object opened for writing.
|
|
# @param **options Options, given as keyword arguments.
|
|
# @keyparam encoding Optional output encoding (default is US-ASCII).
|
|
# Use "unicode" to return a Unicode string.
|
|
# @keyparam method Optional output method ("xml", "html", "text" or
|
|
# "c14n"; default is "xml").
|
|
# @keyparam xml_declaration Controls if an XML declaration should
|
|
# be added to the file. Use False for never, True for always,
|
|
# None for only if not US-ASCII or UTF-8 or Unicode. None is default.
|
|
|
|
def write(self, file_or_filename,
|
|
# keyword arguments
|
|
encoding=None,
|
|
xml_declaration=None,
|
|
default_namespace=None,
|
|
method=None):
|
|
# assert self._root is not None
|
|
if not method:
|
|
method = "xml"
|
|
elif method not in _serialize:
|
|
# FIXME: raise an ImportError for c14n if ElementC14N is missing?
|
|
raise ValueError("unknown method %r" % method)
|
|
if not encoding:
|
|
if method == "c14n":
|
|
encoding = "utf-8"
|
|
else:
|
|
encoding = "us-ascii"
|
|
elif encoding == str: # lxml.etree compatibility.
|
|
encoding = "unicode"
|
|
else:
|
|
encoding = encoding.lower()
|
|
if hasattr(file_or_filename, "write"):
|
|
file = file_or_filename
|
|
else:
|
|
if encoding != "unicode":
|
|
file = open(file_or_filename, "wb")
|
|
else:
|
|
file = open(file_or_filename, "w")
|
|
if encoding != "unicode":
|
|
def write(text):
|
|
try:
|
|
return file.write(text.encode(encoding,
|
|
"xmlcharrefreplace"))
|
|
except (TypeError, AttributeError):
|
|
_raise_serialization_error(text)
|
|
else:
|
|
write = file.write
|
|
if method == "xml" and (xml_declaration or
|
|
(xml_declaration is None and
|
|
encoding not in ("utf-8", "us-ascii", "unicode"))):
|
|
declared_encoding = encoding
|
|
if encoding == "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)
|
|
if file_or_filename is not file:
|
|
file.close()
|
|
|
|
def write_c14n(self, file):
|
|
# lxml.etree compatibility. use output method instead
|
|
return self.write(file, method="c14n")
|
|
|
|
# --------------------------------------------------------------------
|
|
# serialization support
|
|
|
|
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
|
|
try:
|
|
iterate = elem.iter
|
|
except AttributeError:
|
|
iterate = elem.getiterator # cET compatibility
|
|
for elem in iterate():
|
|
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):
|
|
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)
|
|
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):
|
|
write(">")
|
|
if text:
|
|
write(_escape_cdata(text))
|
|
for e in elem:
|
|
_serialize_xml(write, e, qnames, None)
|
|
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):
|
|
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(">")
|
|
tag = tag.lower()
|
|
if text:
|
|
if tag == "script" or tag == "style":
|
|
write(text)
|
|
else:
|
|
write(_escape_cdata(text))
|
|
for e in elem:
|
|
_serialize_html(write, e, qnames, None)
|
|
if tag 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,
|
|
}
|
|
|
|
##
|
|
# Registers a namespace prefix. The registry is global, and any
|
|
# existing mapping for either the given prefix or the namespace URI
|
|
# will be removed.
|
|
#
|
|
# @param prefix Namespace prefix.
|
|
# @param uri Namespace uri. Tags and attributes in this namespace
|
|
# will be serialized with the given prefix, if at all possible.
|
|
# @exception ValueError If the prefix is reserved, or is otherwise
|
|
# invalid.
|
|
|
|
def register_namespace(prefix, uri):
|
|
if re.match("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)
|
|
|
|
# --------------------------------------------------------------------
|
|
|
|
##
|
|
# Generates a string representation of an XML element, including all
|
|
# subelements. If encoding is "unicode", the return type is a string;
|
|
# otherwise it is a bytes array.
|
|
#
|
|
# @param element An Element instance.
|
|
# @keyparam encoding Optional output encoding (default is US-ASCII).
|
|
# Use "unicode" to return a Unicode string.
|
|
# @keyparam method Optional output method ("xml", "html", "text" or
|
|
# "c14n"; default is "xml").
|
|
# @return An (optionally) encoded string containing the XML data.
|
|
# @defreturn string
|
|
|
|
def tostring(element, encoding=None, method=None):
|
|
class dummy:
|
|
pass
|
|
data = []
|
|
file = dummy()
|
|
file.write = data.append
|
|
ElementTree(element).write(file, encoding, method=method)
|
|
if encoding in (str, "unicode"):
|
|
return "".join(data)
|
|
else:
|
|
return b"".join(data)
|
|
|
|
##
|
|
# Generates a string representation of an XML element, including all
|
|
# subelements. If encoding is False, the string is returned as a
|
|
# sequence of string fragments; otherwise it is a sequence of
|
|
# bytestrings.
|
|
#
|
|
# @param element An Element instance.
|
|
# @keyparam encoding Optional output encoding (default is US-ASCII).
|
|
# Use "unicode" to return a Unicode string.
|
|
# @keyparam method Optional output method ("xml", "html", "text" or
|
|
# "c14n"; default is "xml").
|
|
# @return A sequence object containing the XML data.
|
|
# @defreturn sequence
|
|
# @since 1.3
|
|
|
|
def tostringlist(element, encoding=None, method=None):
|
|
class dummy:
|
|
pass
|
|
data = []
|
|
file = dummy()
|
|
file.write = data.append
|
|
ElementTree(element).write(file, encoding, method=method)
|
|
# FIXME: merge small fragments into larger parts
|
|
return data
|
|
|
|
##
|
|
# Writes an element tree or element structure to sys.stdout. This
|
|
# function should be used for debugging only.
|
|
# <p>
|
|
# The exact output format is implementation dependent. In this
|
|
# version, it's written as an ordinary XML file.
|
|
#
|
|
# @param elem An element tree or an individual element.
|
|
|
|
def dump(elem):
|
|
# 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
|
|
|
|
##
|
|
# Parses an XML document into an element tree.
|
|
#
|
|
# @param source A filename or file object containing XML data.
|
|
# @param parser An optional parser instance. If not given, the
|
|
# standard {@link XMLParser} parser is used.
|
|
# @return An ElementTree instance
|
|
|
|
def parse(source, parser=None):
|
|
tree = ElementTree()
|
|
tree.parse(source, parser)
|
|
return tree
|
|
|
|
##
|
|
# Parses an XML document into an element tree incrementally, and reports
|
|
# what's going on to the user.
|
|
#
|
|
# @param source A filename or file object containing XML data.
|
|
# @param events A list of events to report back. If omitted, only "end"
|
|
# events are reported.
|
|
# @param parser An optional parser instance. If not given, the
|
|
# standard {@link XMLParser} parser is used.
|
|
# @return A (event, elem) iterator.
|
|
|
|
def iterparse(source, events=None, parser=None):
|
|
close_source = False
|
|
if not hasattr(source, "read"):
|
|
source = open(source, "rb")
|
|
close_source = True
|
|
if not parser:
|
|
parser = XMLParser(target=TreeBuilder())
|
|
return _IterParseIterator(source, events, parser, close_source)
|
|
|
|
class _IterParseIterator:
|
|
|
|
def __init__(self, source, events, parser, close_source=False):
|
|
self._file = source
|
|
self._close_file = close_source
|
|
self._events = []
|
|
self._index = 0
|
|
self._error = None
|
|
self.root = self._root = None
|
|
self._parser = parser
|
|
# wire up the parser for event reporting
|
|
parser = self._parser._parser
|
|
append = self._events.append
|
|
if events is None:
|
|
events = ["end"]
|
|
for event in events:
|
|
if event == "start":
|
|
try:
|
|
parser.ordered_attributes = 1
|
|
parser.specified_attributes = 1
|
|
def handler(tag, attrib_in, event=event, append=append,
|
|
start=self._parser._start_list):
|
|
append((event, start(tag, attrib_in)))
|
|
parser.StartElementHandler = handler
|
|
except AttributeError:
|
|
def handler(tag, attrib_in, event=event, append=append,
|
|
start=self._parser._start):
|
|
append((event, start(tag, attrib_in)))
|
|
parser.StartElementHandler = handler
|
|
elif event == "end":
|
|
def handler(tag, event=event, append=append,
|
|
end=self._parser._end):
|
|
append((event, end(tag)))
|
|
parser.EndElementHandler = handler
|
|
elif event == "start-ns":
|
|
def handler(prefix, uri, event=event, append=append):
|
|
append((event, (prefix or "", uri or "")))
|
|
parser.StartNamespaceDeclHandler = handler
|
|
elif event == "end-ns":
|
|
def handler(prefix, event=event, append=append):
|
|
append((event, None))
|
|
parser.EndNamespaceDeclHandler = handler
|
|
else:
|
|
raise ValueError("unknown event %r" % event)
|
|
|
|
def __next__(self):
|
|
while 1:
|
|
try:
|
|
item = self._events[self._index]
|
|
self._index += 1
|
|
return item
|
|
except IndexError:
|
|
pass
|
|
if self._error:
|
|
e = self._error
|
|
self._error = None
|
|
raise e
|
|
if self._parser is None:
|
|
self.root = self._root
|
|
if self._close_file:
|
|
self._file.close()
|
|
raise StopIteration
|
|
# load event buffer
|
|
del self._events[:]
|
|
self._index = 0
|
|
data = self._file.read(16384)
|
|
if data:
|
|
try:
|
|
self._parser.feed(data)
|
|
except SyntaxError as exc:
|
|
self._error = exc
|
|
else:
|
|
self._root = self._parser.close()
|
|
self._parser = None
|
|
|
|
def __iter__(self):
|
|
return self
|
|
|
|
##
|
|
# Parses an XML document from a string constant. This function can
|
|
# be used to embed "XML literals" in Python code.
|
|
#
|
|
# @param source A string containing XML data.
|
|
# @param parser An optional parser instance. If not given, the
|
|
# standard {@link XMLParser} parser is used.
|
|
# @return An Element instance.
|
|
# @defreturn Element
|
|
|
|
def XML(text, parser=None):
|
|
if not parser:
|
|
parser = XMLParser(target=TreeBuilder())
|
|
parser.feed(text)
|
|
return parser.close()
|
|
|
|
##
|
|
# Parses an XML document from a string constant, and also returns
|
|
# a dictionary which maps from element id:s to elements.
|
|
#
|
|
# @param source A string containing XML data.
|
|
# @param parser An optional parser instance. If not given, the
|
|
# standard {@link XMLParser} parser is used.
|
|
# @return A tuple containing an Element instance and a dictionary.
|
|
# @defreturn (Element, dictionary)
|
|
|
|
def XMLID(text, parser=None):
|
|
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
|
|
|
|
##
|
|
# Parses an XML document from a string constant. Same as {@link #XML}.
|
|
#
|
|
# @def fromstring(text)
|
|
# @param source A string containing XML data.
|
|
# @return An Element instance.
|
|
# @defreturn Element
|
|
|
|
fromstring = XML
|
|
|
|
##
|
|
# Parses an XML document from a sequence of string fragments.
|
|
#
|
|
# @param sequence A list or other sequence containing XML data fragments.
|
|
# @param parser An optional parser instance. If not given, the
|
|
# standard {@link XMLParser} parser is used.
|
|
# @return An Element instance.
|
|
# @defreturn Element
|
|
# @since 1.3
|
|
|
|
def fromstringlist(sequence, parser=None):
|
|
if not parser:
|
|
parser = XMLParser(target=TreeBuilder())
|
|
for text in sequence:
|
|
parser.feed(text)
|
|
return parser.close()
|
|
|
|
# --------------------------------------------------------------------
|
|
|
|
##
|
|
# Generic element structure builder. This builder converts a sequence
|
|
# of {@link #TreeBuilder.start}, {@link #TreeBuilder.data}, and {@link
|
|
# #TreeBuilder.end} method calls to a well-formed element structure.
|
|
# <p>
|
|
# You can use this class to build an element structure using a custom XML
|
|
# parser, or a parser for some other XML-like format.
|
|
#
|
|
# @param element_factory Optional element factory. This factory
|
|
# is called to create new Element instances, as necessary.
|
|
|
|
class TreeBuilder:
|
|
|
|
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
|
|
|
|
##
|
|
# Flushes the builder buffers, and returns the toplevel document
|
|
# element.
|
|
#
|
|
# @return An Element instance.
|
|
# @defreturn Element
|
|
|
|
def close(self):
|
|
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 = []
|
|
|
|
##
|
|
# Adds text to the current element.
|
|
#
|
|
# @param data A string. This should be either an 8-bit string
|
|
# containing ASCII text, or a Unicode string.
|
|
|
|
def data(self, data):
|
|
self._data.append(data)
|
|
|
|
##
|
|
# Opens a new element.
|
|
#
|
|
# @param tag The element name.
|
|
# @param attrib A dictionary containing element attributes.
|
|
# @return The opened element.
|
|
# @defreturn Element
|
|
|
|
def start(self, tag, attrs):
|
|
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
|
|
|
|
##
|
|
# Closes the current element.
|
|
#
|
|
# @param tag The element name.
|
|
# @return The closed element.
|
|
# @defreturn Element
|
|
|
|
def end(self, tag):
|
|
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
|
|
|
|
##
|
|
# Element structure builder for XML source data, based on the
|
|
# <b>expat</b> parser.
|
|
#
|
|
# @keyparam target Target object. If omitted, the builder uses an
|
|
# instance of the standard {@link #TreeBuilder} class.
|
|
# @keyparam html Predefine HTML entities. This flag is not supported
|
|
# by the current implementation.
|
|
# @keyparam encoding Optional encoding. If given, the value overrides
|
|
# the encoding specified in the XML file.
|
|
# @see #ElementTree
|
|
# @see #TreeBuilder
|
|
|
|
class XMLParser:
|
|
|
|
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
|
|
# let expat do the buffering, if supported
|
|
try:
|
|
parser.buffer_text = 1
|
|
except AttributeError:
|
|
pass
|
|
# use new-style attribute handling, if supported
|
|
try:
|
|
parser.ordered_attributes = 1
|
|
parser.specified_attributes = 1
|
|
if hasattr(target, 'start'):
|
|
parser.StartElementHandler = self._start_list
|
|
except AttributeError:
|
|
pass
|
|
self._doctype = None
|
|
self.entity = {}
|
|
try:
|
|
self.version = "Expat %d.%d.%d" % expat.version_info
|
|
except AttributeError:
|
|
pass # unknown
|
|
|
|
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, attrib_in):
|
|
fixname = self._fixname
|
|
tag = fixname(tag)
|
|
attrib = {}
|
|
for key, value in attrib_in.items():
|
|
attrib[fixname(key)] = value
|
|
return self.target.start(tag, attrib)
|
|
|
|
def _start_list(self, tag, attrib_in):
|
|
fixname = self._fixname
|
|
tag = fixname(tag)
|
|
attrib = {}
|
|
if attrib_in:
|
|
for i in range(0, len(attrib_in), 2):
|
|
attrib[fixname(attrib_in[i])] = attrib_in[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
|
|
elif type == "SYSTEM" and n == 3:
|
|
name, type, system = self._doctype
|
|
pubid = None
|
|
else:
|
|
return
|
|
if pubid:
|
|
pubid = pubid[1:-1]
|
|
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
|
|
|
|
##
|
|
# (Deprecated) Handles a doctype declaration.
|
|
#
|
|
# @param name Doctype name.
|
|
# @param pubid Public identifier.
|
|
# @param system System identifier.
|
|
|
|
def doctype(self, name, pubid, system):
|
|
"""This method of XMLParser is deprecated."""
|
|
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
|
|
|
|
##
|
|
# Feeds data to the parser.
|
|
#
|
|
# @param data Encoded data.
|
|
|
|
def feed(self, data):
|
|
try:
|
|
self.parser.Parse(data, 0)
|
|
except self._error as v:
|
|
self._raiseerror(v)
|
|
|
|
##
|
|
# Finishes feeding data to the parser.
|
|
#
|
|
# @return An element structure.
|
|
# @defreturn Element
|
|
|
|
def close(self):
|
|
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, SubElement, ParseError, TreeBuilder, XMLParser
|
|
from _elementtree import *
|
|
except ImportError:
|
|
pass
|
|
else:
|
|
# Overwrite 'ElementTree.parse' and 'iterparse' to use the C XMLParser
|
|
|
|
class ElementTree(ElementTree):
|
|
def parse(self, source, parser=None):
|
|
close_source = False
|
|
if not hasattr(source, 'read'):
|
|
source = open(source, 'rb')
|
|
close_source = True
|
|
try:
|
|
if parser is not None:
|
|
while True:
|
|
data = source.read(65536)
|
|
if not data:
|
|
break
|
|
parser.feed(data)
|
|
self._root = parser.close()
|
|
else:
|
|
parser = XMLParser()
|
|
self._root = parser._parse(source)
|
|
return self._root
|
|
finally:
|
|
if close_source:
|
|
source.close()
|
|
|
|
class iterparse:
|
|
root = None
|
|
def __init__(self, file, events=None):
|
|
self._close_file = False
|
|
if not hasattr(file, 'read'):
|
|
file = open(file, 'rb')
|
|
self._close_file = True
|
|
self._file = file
|
|
self._events = []
|
|
self._index = 0
|
|
self._error = None
|
|
self.root = self._root = None
|
|
b = TreeBuilder()
|
|
self._parser = XMLParser(b)
|
|
self._parser._setevents(self._events, events)
|
|
|
|
def __next__(self):
|
|
while True:
|
|
try:
|
|
item = self._events[self._index]
|
|
self._index += 1
|
|
return item
|
|
except IndexError:
|
|
pass
|
|
if self._error:
|
|
e = self._error
|
|
self._error = None
|
|
raise e
|
|
if self._parser is None:
|
|
self.root = self._root
|
|
if self._close_file:
|
|
self._file.close()
|
|
raise StopIteration
|
|
# load event buffer
|
|
del self._events[:]
|
|
self._index = 0
|
|
data = self._file.read(16384)
|
|
if data:
|
|
try:
|
|
self._parser.feed(data)
|
|
except SyntaxError as exc:
|
|
self._error = exc
|
|
else:
|
|
self._root = self._parser.close()
|
|
self._parser = None
|
|
|
|
def __iter__(self):
|
|
return self
|
|
|
|
# compatibility
|
|
XMLTreeBuilder = XMLParser
|
|
|
|
# workaround circular import.
|
|
try:
|
|
from ElementC14N import _serialize_c14n
|
|
_serialize["c14n"] = _serialize_c14n
|
|
except ImportError:
|
|
pass
|