name : ElementInclude.py # # ElementTree # $Id: ElementInclude.py 3375 2008-02-13 08:05:08Z 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) 1999-2008 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/psf/license for licensing details. ## # Limited XInclude support for the ElementTree package. ## import copy from . 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): with open(href) as file: if parse == "xml": data = ElementTree.parse(file).getroot() else: data = file.read() if encoding: data = data.decode(encoding) 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 + (e.tail or "") 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