Thuban/Model/xmlwriter.py

# Copyright (c) 2003, 2005 by Intevation GmbH
# Authors:
# Jonathan Coles <[email protected]>
#
# This program is free software under the GPL (>=v2)
# Read the file COPYING coming with Thuban for details.

"""
Functions to save an XML file
"""

__version__ = "$Revision$"

import os
from types import UnicodeType

from Thuban import unicode_from_internal

#
# one level of indention
#
TAB = "    "

def escape(data):
    """Escape &, \", ', <, and > in a string of data.
    """
    data = data.replace("&", "&amp;")
    data = data.replace("<", "&lt;")
    data = data.replace(">", "&gt;")
    data = data.replace('"', "&quot;")
    data = data.replace("'", "&apos;")
    return data

class XMLWriter:
    """Abstract XMLWriter.

    Should be overridden to provide specific object saving functionality.
    """

    def __init__(self):
        self.filename = None
        pass

    def write(self, file_or_filename):
        """Write the session to a file.

        The argument may be either a file object or a filename. If it's
        a filename, the file will be opened for writing. Files of
        shapefiles will be stored as filenames relative to the directory
        the file is stored in (as given by os.path.dirname(filename)) if
        they have a common parent directory other than the root
        directory.

        If the argument is a file object (which is determined by the
        presence of a write method) all filenames will be absolute
        filenames.
        """

        # keep track of how many levels of indentation to write
        self.indent_level = 0 
        # track whether an element is currently open. see open_element().
        self.element_open = 0

        if hasattr(file_or_filename, "write"):
            # it's a file object
            self.file = file_or_filename
            self.dir = ""
        else:
            self.filename = file_or_filename
            self.dir = os.path.dirname(self.filename)
            self.file = open(self.filename, 'w')

    def close(self):
        assert self.indent_level == 0
        if self.filename is not None:
            self.file.close()

    def write_header(self, doctype, system):
        """Write the XML header"""
        self.file.write('<?xml version="1.0" encoding="UTF-8"?>\n')
        self.file.write('<!DOCTYPE %s SYSTEM "%s">\n' % (doctype, system))

    def open_element(self, element, attrs = {}):

        #
        # we note when an element is opened so that if two open_element()
        # calls are made successively we can end the currently open
        # tag and will later write a proper close tag. otherwise,
        # if a close_element() call is made directly after an open_element()
        # call we will close the tag with a />
        #
        if self.element_open == 1:
            self.file.write(">\n")

        self.element_open = 1

        # Helper function to write an element open tag with attributes
        self.file.write("%s<%s" % (TAB*self.indent_level, element))
        self.__write_attribs(attrs)

        self.indent_level += 1

    def close_element(self, element):
        self.indent_level -= 1
        assert self.indent_level >= 0

        # see open_element() for an explanation
        if self.element_open == 1:
            self.element_open = 0
            self.file.write("/>\n")
        else:
            self.file.write("%s</%s>\n" % (TAB*self.indent_level, element))

    def write_element(self, element, attrs = {}):
        """write an element that won't need a closing tag"""
        self.open_element(element, attrs)
        self.close_element(element)

    def __write_attribs(self, attrs):
        for name, value in attrs.items():
            self.file.write(' %s="%s"' % (self.encode(name), 
                                          self.encode(value)))

    def encode(self, s):
        """Return an XML-escaped and UTF-8 encoded copy of the string s.

        The parameter must be a string in Thuban's internal string
        representation or a unicode object.
        """
        if not isinstance(s, unicode):
            s = unicode_from_internal(s)
        return escape(s).encode("utf8")
1	# Copyright (c) 2003, 2005 by Intevation GmbH
2	# Authors:
3	# Jonathan Coles <[email protected]>
4	#
5	# This program is free software under the GPL (>=v2)
6	# Read the file COPYING coming with Thuban for details.
7
8	"""
9	Functions to save an XML file
10	"""
11
12	__version__ = "$Revision$"
13
14	import os
15	from types import UnicodeType
16
17	from Thuban import unicode_from_internal
18
19	#
20	# one level of indention
21	#
22	TAB = " "
23
24	def escape(data):
25	"""Escape &, \", ', <, and > in a string of data.
26	"""
27	data = data.replace("&", "&")
28	data = data.replace("<", "<")
29	data = data.replace(">", ">")
30	data = data.replace('"', """)
31	data = data.replace("'", "'")
32	return data
33
34	class XMLWriter:
35	"""Abstract XMLWriter.
36
37	Should be overridden to provide specific object saving functionality.
38	"""
39
40	def __init__(self):
41	self.filename = None
42	pass
43
44	def write(self, file_or_filename):
45	"""Write the session to a file.
46
47	The argument may be either a file object or a filename. If it's
48	a filename, the file will be opened for writing. Files of
49	shapefiles will be stored as filenames relative to the directory
50	the file is stored in (as given by os.path.dirname(filename)) if
51	they have a common parent directory other than the root
52	directory.
53
54	If the argument is a file object (which is determined by the
55	presence of a write method) all filenames will be absolute
56	filenames.
57	"""
58
59	# keep track of how many levels of indentation to write
60	self.indent_level = 0
61	# track whether an element is currently open. see open_element().
62	self.element_open = 0
63
64	if hasattr(file_or_filename, "write"):
65	# it's a file object
66	self.file = file_or_filename
67	self.dir = ""
68	else:
69	self.filename = file_or_filename
70	self.dir = os.path.dirname(self.filename)
71	self.file = open(self.filename, 'w')
72
73	def close(self):
74	assert self.indent_level == 0
75	if self.filename is not None:
76	self.file.close()
77
78	def write_header(self, doctype, system):
79	"""Write the XML header"""
80	self.file.write('<?xml version="1.0" encoding="UTF-8"?>\n')
81	self.file.write('<!DOCTYPE %s SYSTEM "%s">\n' % (doctype, system))
82
83	def open_element(self, element, attrs = {}):
84
85	#
86	# we note when an element is opened so that if two open_element()
87	# calls are made successively we can end the currently open
88	# tag and will later write a proper close tag. otherwise,
89	# if a close_element() call is made directly after an open_element()
90	# call we will close the tag with a />
91	#
92	if self.element_open == 1:
93	self.file.write(">\n")
94
95	self.element_open = 1
96
97	# Helper function to write an element open tag with attributes
98	self.file.write("%s<%s" % (TAB*self.indent_level, element))
99	self.__write_attribs(attrs)
100
101	self.indent_level += 1
102
103	def close_element(self, element):
104	self.indent_level -= 1
105	assert self.indent_level >= 0
106
107	# see open_element() for an explanation
108	if self.element_open == 1:
109	self.element_open = 0
110	self.file.write("/>\n")
111	else:
112	self.file.write("%s</%s>\n" % (TAB*self.indent_level, element))
113
114	def write_element(self, element, attrs = {}):
115	"""write an element that won't need a closing tag"""
116	self.open_element(element, attrs)
117	self.close_element(element)
118
119	def __write_attribs(self, attrs):
120	for name, value in attrs.items():
121	self.file.write(' %s="%s"' % (self.encode(name),
122	self.encode(value)))
123
124	def encode(self, s):
125	"""Return an XML-escaped and UTF-8 encoded copy of the string s.
126
127	The parameter must be a string in Thuban's internal string
128	representation or a unicode object.
129	"""
130	if not isinstance(s, unicode):
131	s = unicode_from_internal(s)
132	return escape(s).encode("utf8")
Name	Value
svn:eol-style	native
svn:keywords	Author Date Id Revision