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- #
- # ElementTree
- # $Id: ElementInclude.py 1862 2004-06-18 07:31:02Z Fredrik $
- #
- # limited xinclude support for element trees
- #
- # history:
- # 2003-08-15 fl created
- # 2003-11-14 fl fixed default loader
- #
- # Copyright (c) 2003-2004 by Fredrik Lundh. All rights reserved.
- #
- # fredrik@pythonware.com
- # http://www.pythonware.com
- #
- # --------------------------------------------------------------------
- # The ElementTree toolkit is
- #
- # Copyright (c) 1999-2004 by Fredrik Lundh
- #
- # By obtaining, using, and/or copying this software and/or its
- # associated documentation, you agree that you have read, understood,
- # and will comply with the following terms and conditions:
- #
- # Permission to use, copy, modify, and distribute this software and
- # its associated documentation for any purpose and without fee is
- # hereby granted, provided that the above copyright notice appears in
- # all copies, and that both that copyright notice and this permission
- # notice appear in supporting documentation, and that the name of
- # Secret Labs AB or the author not be used in advertising or publicity
- # pertaining to distribution of the software without specific, written
- # prior permission.
- #
- # SECRET LABS AB AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD
- # TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANT-
- # ABILITY AND FITNESS. IN NO EVENT SHALL SECRET LABS AB OR THE AUTHOR
- # BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
- # DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
- # WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
- # ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
- # OF THIS SOFTWARE.
- # --------------------------------------------------------------------
-
- # Licensed to PSF under a Contributor Agreement.
- # See http://www.python.org/2.4/license for licensing details.
-
- ##
- # Limited XInclude support for the ElementTree package.
- ##
-
- import copy
- import ElementTree
-
- XINCLUDE = "{http://www.w3.org/2001/XInclude}"
-
- XINCLUDE_INCLUDE = XINCLUDE + "include"
- XINCLUDE_FALLBACK = XINCLUDE + "fallback"
-
- ##
- # Fatal include error.
-
- class FatalIncludeError(SyntaxError):
- pass
-
- ##
- # Default loader. This loader reads an included resource from disk.
- #
- # @param href Resource reference.
- # @param parse Parse mode. Either "xml" or "text".
- # @param encoding Optional text encoding.
- # @return The expanded resource. If the parse mode is "xml", this
- # is an ElementTree instance. If the parse mode is "text", this
- # is a Unicode string. If the loader fails, it can return None
- # or raise an IOError exception.
- # @throws IOError If the loader fails to load the resource.
-
- def default_loader(href, parse, encoding=None):
- file = open(href)
- if parse == "xml":
- data = ElementTree.parse(file).getroot()
- else:
- data = file.read()
- if encoding:
- data = data.decode(encoding)
- file.close()
- return data
-
- ##
- # Expand XInclude directives.
- #
- # @param elem Root element.
- # @param loader Optional resource loader. If omitted, it defaults
- # to {@link default_loader}. If given, it should be a callable
- # that implements the same interface as <b>default_loader</b>.
- # @throws FatalIncludeError If the function fails to include a given
- # resource, or if the tree contains malformed XInclude elements.
- # @throws IOError If the function fails to load a given resource.
-
- def include(elem, loader=None):
- if loader is None:
- loader = default_loader
- # look for xinclude elements
- i = 0
- while i < len(elem):
- e = elem[i]
- if e.tag == XINCLUDE_INCLUDE:
- # process xinclude directive
- href = e.get("href")
- parse = e.get("parse", "xml")
- if parse == "xml":
- node = loader(href, parse)
- if node is None:
- raise FatalIncludeError(
- "cannot load %r as %r" % (href, parse)
- )
- node = copy.copy(node)
- if e.tail:
- node.tail = (node.tail or "") + e.tail
- elem[i] = node
- elif parse == "text":
- text = loader(href, parse, e.get("encoding"))
- if text is None:
- raise FatalIncludeError(
- "cannot load %r as %r" % (href, parse)
- )
- if i:
- node = elem[i-1]
- node.tail = (node.tail or "") + text
- else:
- elem.text = (elem.text or "") + text + (e.tail or "")
- del elem[i]
- continue
- else:
- raise FatalIncludeError(
- "unknown parse type in xi:include tag (%r)" % parse
- )
- elif e.tag == XINCLUDE_FALLBACK:
- raise FatalIncludeError(
- "xi:fallback tag must be child of xi:include (%r)" % e.tag
- )
- else:
- include(e, loader)
- i = i + 1
-