1 # 2 # ElementTree 3 # $Id: ElementInclude.py 3375 2008-02-13 08:05:08Z fredrik $ 4 # 5 # limited xinclude support for element trees 6 # 7 # history: 8 # 2003-08-15 fl created 9 # 2003-11-14 fl fixed default loader 10 # 11 # Copyright (c) 2003-2004 by Fredrik Lundh. All rights reserved. 12 # 13 # fredrik (at] pythonware.com 14 # http://www.pythonware.com 15 # 16 # -------------------------------------------------------------------- 17 # The ElementTree toolkit is 18 # 19 # Copyright (c) 1999-2008 by Fredrik Lundh 20 # 21 # By obtaining, using, and/or copying this software and/or its 22 # associated documentation, you agree that you have read, understood, 23 # and will comply with the following terms and conditions: 24 # 25 # Permission to use, copy, modify, and distribute this software and 26 # its associated documentation for any purpose and without fee is 27 # hereby granted, provided that the above copyright notice appears in 28 # all copies, and that both that copyright notice and this permission 29 # notice appear in supporting documentation, and that the name of 30 # Secret Labs AB or the author not be used in advertising or publicity 31 # pertaining to distribution of the software without specific, written 32 # prior permission. 33 # 34 # SECRET LABS AB AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD 35 # TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANT- 36 # ABILITY AND FITNESS. IN NO EVENT SHALL SECRET LABS AB OR THE AUTHOR 37 # BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY 38 # DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, 39 # WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS 40 # ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE 41 # OF THIS SOFTWARE. 42 # -------------------------------------------------------------------- 43 44 # Licensed to PSF under a Contributor Agreement. 45 # See http://www.python.org/psf/license for licensing details. 46 47 ## 48 # Limited XInclude support for the ElementTree package. 49 ## 50 51 import copy 52 from . import ElementTree 53 54 XINCLUDE = "{http://www.w3.org/2001/XInclude}" 55 56 XINCLUDE_INCLUDE = XINCLUDE + "include" 57 XINCLUDE_FALLBACK = XINCLUDE + "fallback" 58 59 ## 60 # Fatal include error. 61 62 class FatalIncludeError(SyntaxError): 63 pass 64 65 ## 66 # Default loader. This loader reads an included resource from disk. 67 # 68 # @param href Resource reference. 69 # @param parse Parse mode. Either "xml" or "text". 70 # @param encoding Optional text encoding. 71 # @return The expanded resource. If the parse mode is "xml", this 72 # is an ElementTree instance. If the parse mode is "text", this 73 # is a Unicode string. If the loader fails, it can return None 74 # or raise an IOError exception. 75 # @throws IOError If the loader fails to load the resource. 76 77 def default_loader(href, parse, encoding=None): 78 file = open(href) 79 if parse == "xml": 80 data = ElementTree.parse(file).getroot() 81 else: 82 data = file.read() 83 if encoding: 84 data = data.decode(encoding) 85 file.close() 86 return data 87 88 ## 89 # Expand XInclude directives. 90 # 91 # @param elem Root element. 92 # @param loader Optional resource loader. If omitted, it defaults 93 # to {@link default_loader}. If given, it should be a callable 94 # that implements the same interface as <b>default_loader</b>. 95 # @throws FatalIncludeError If the function fails to include a given 96 # resource, or if the tree contains malformed XInclude elements. 97 # @throws IOError If the function fails to load a given resource. 98 99 def include(elem, loader=None): 100 if loader is None: 101 loader = default_loader 102 # look for xinclude elements 103 i = 0 104 while i < len(elem): 105 e = elem[i] 106 if e.tag == XINCLUDE_INCLUDE: 107 # process xinclude directive 108 href = e.get("href") 109 parse = e.get("parse", "xml") 110 if parse == "xml": 111 node = loader(href, parse) 112 if node is None: 113 raise FatalIncludeError( 114 "cannot load %r as %r" % (href, parse) 115 ) 116 node = copy.copy(node) 117 if e.tail: 118 node.tail = (node.tail or "") + e.tail 119 elem[i] = node 120 elif parse == "text": 121 text = loader(href, parse, e.get("encoding")) 122 if text is None: 123 raise FatalIncludeError( 124 "cannot load %r as %r" % (href, parse) 125 ) 126 if i: 127 node = elem[i-1] 128 node.tail = (node.tail or "") + text + (e.tail or "") 129 else: 130 elem.text = (elem.text or "") + text + (e.tail or "") 131 del elem[i] 132 continue 133 else: 134 raise FatalIncludeError( 135 "unknown parse type in xi:include tag (%r)" % parse 136 ) 137 elif e.tag == XINCLUDE_FALLBACK: 138 raise FatalIncludeError( 139 "xi:fallback tag must be child of xi:include (%r)" % e.tag 140 ) 141 else: 142 include(e, loader) 143 i = i + 1 144
