Thuban/Model/load.py

# Copyright (C) 2001, 2002, 2003 by Intevation GmbH
# Authors:
# Jan-Oliver Wagner <[email protected]>
# Bernhard Herzog <[email protected]>
# Jonathan Coles <[email protected]>
#
# This program is free software under the GPL (>=v2)
# Read the file COPYING coming with GRASS for details.

"""
Parser for thuban session files.
"""

__version__ = "$Revision$"

import string, os

import xml.sax
import xml.sax.handler
from xml.sax import make_parser, ErrorHandler, SAXNotRecognizedException

from Thuban import _
from Thuban.common import *

from Thuban.Model.table import FIELDTYPE_INT, FIELDTYPE_DOUBLE, \
     FIELDTYPE_STRING

from Thuban.Model.session import Session
from Thuban.Model.map import Map
from Thuban.Model.layer import Layer
from Thuban.Model.color import Color
from Thuban.Model.proj import Projection
from Thuban.Model.classification import Classification, \
    ClassGroupDefault, ClassGroupSingleton, ClassGroupRange, ClassGroupMap, \
    ClassGroupProperties


def parse_color(color):
    """Return the color object for the string color.

    Color may be either 'None' or of the form '#RRGGBB' in the usual
    HTML color notation
    """
    color = string.strip(color)
    if color == "None":
        result = Color.Transparent
    elif color[0] == '#':
        if len(color) == 7:
            r = string.atoi(color[1:3], 16) / 255.0
            g = string.atoi(color[3:5], 16) / 255.0
            b = string.atoi(color[5:7], 16) / 255.0
            result = Color(r, g, b)
        else:
            raise ValueError(_("Invalid hexadecimal color specification %s")
                             % color)
    else:
        raise ValueError(_("Invalid color specification %s") % color)
    return result


class XMLReader(xml.sax.handler.ContentHandler):

    # Dictionary mapping element names (or (URI, element name) pairs for
    # documents using namespaces) to method names. The methods should
    # accept the same parameters as the startElement (or startElementNS)
    # methods. The start_dispatcher is used by the default startElement
    # and startElementNS methods to call a method for the open tag of an
    # element.
    start_dispatcher = {}

    # end_dispatcher works just like start_dispatcher but it's used by
    # endElement and endElementNS. The method whose names it maps to
    # should accept the same parameters as endElement and endElementNS.
    end_dispatcher = {}


    def __init__(self):
        self.chars = ''
        self.__parser = None
        self.__directory = ""
        self.__dispatchers = {}

    def read(self, file_or_filename):

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

        if self.__parser is None:
            self.__parser = make_parser()
            self.__parser.setContentHandler(self)
            self.__parser.setErrorHandler(ErrorHandler())
            self.__parser.setFeature(xml.sax.handler.feature_namespaces, 1)

            #
            # Well, this isn't pretty, but it appears that if you
            # use Python 2.2 without the site-package _xmlplus then
            # the following will fail, and without them it will work.
            # However, if you do have the site-package and you don't
            # call these functions, the reader raises an exception
            #
            # The reason we set these to 0 in the first place is 
            # because there is an unresolved issue with external
            # entities causing an exception in the reader
            #
            try:
                self.__parser.setFeature(xml.sax.handler.feature_validation,0)
                self.__parser.setFeature(xml.sax.handler.feature_external_ges,0)
                self.__parser.setFeature(xml.sax.handler.feature_external_pes,0)
            except SAXNotRecognizedException:
                pass

        self.__parser.parse(self.__file)

        self.close()

    def close(self):
        self.__file.close()
        
    def GetFileName(self):
        if hasattr(self.__file, "name"):
            return self.__file.name

        return ""

    def GetDirectory(self):
        return self.__directory


    def AddDispatchers(self, dict):
        """Add the function names that should be used to process XML tags.

        dict -- a dictionary whose keys are XML tag strings and whose values
                are pairs of strings such that the first string is
                the name of the function that should be called when the
                XML tag opens and the second string is the name of the
                function that should be called when the XML tag closes.
                If a pair element is None, no function is called.
        """

        self.__dispatchers.update(dict)

    def startElementNS(self, name, qname, attrs):
        """Call the method given for name in self.start_dispatcher
        """
        if name[0] is None:
            method_name = self.__dispatchers.get(name[1])
        else:
            # Dispatch with namespace
            method_name = self.__dispatchers.get(name)
        if method_name is not None and method_name[0] is not None:
            getattr(self, method_name[0])(name, qname, attrs)

    def endElementNS(self, name, qname):
        """Call the method given for name in self.end_dispatcher
        """
        if name[0] is None:
            method_name = self.__dispatchers.get(name[1])
        else:
            # Dispatch with namespace
            method_name = self.__dispatchers.get(name)
        if method_name is not None and method_name[1] is not None:
            getattr(self, method_name[1])(name, qname)

class SessionLoader(XMLReader):

    def __init__(self):
        """Inititialize the Sax handler."""
        XMLReader.__init__(self)

        self.theSession = None
        self.aMap = None
        self.aLayer = None

        XMLReader.AddDispatchers(self,
            {'session'       : ("start_session",        "end_session"),
             'map'           : ("start_map",            "end_map"),
             'projection'    : ("start_projection",     "end_projection"),
             'parameter'     : ("start_parameter",      None),
             'layer'         : ("start_layer",          "end_layer"),
             'classification': ("start_classification", "end_classification"),
             'clnull'        : ("start_clnull",         "end_clnull"),
             'clpoint'       : ("start_clpoint",        "end_clpoint"),
             'clrange'       : ("start_clrange",        "end_clrange"),
             'cldata'        : ("start_cldata",         "end_cldata"),
             'table'         : ("start_table",          "end_table"),
             'labellayer'    : ("start_labellayer",     None),
             'label'         : ("start_label",          None)})

    def start_session(self, name, qname, attrs):
        self.theSession = Session(attrs.get((None, 'title'), None))

    def end_session(self, name, qname):
        pass

    def start_map(self, name, qname, attrs):
        """Start a map."""
        self.aMap = Map(attrs.get((None, 'title'), None))

    def end_map(self, name, qname):
        self.theSession.AddMap(self.aMap)

    def start_projection(self, name, qname, attrs):
        self.ProjectionParams = [ ]

    def end_projection(self, name, qname):
        self.aMap.SetProjection(Projection(self.ProjectionParams))

    def start_parameter(self, name, qname, attrs):
        s = attrs.get((None, 'value'))
        s = str(s) # we can't handle unicode in proj
        self.ProjectionParams.append(s)

    def start_layer(self, name, qname, attrs, layer_class = Layer):
        """Start a layer

        Instantiate a layer of class layer_class from the attributes in
        attrs which may be a dictionary as well as the normal SAX attrs
        object and bind it to self.aLayer.
        """
        title = attrs.get((None, 'title'), "")
        filename = attrs.get((None, 'filename'), "")
        filename = os.path.join(self.GetDirectory(), filename)
        fill = parse_color(attrs.get((None, 'fill'), "None"))
        stroke = parse_color(attrs.get((None, 'stroke'), "#000000"))
        stroke_width = int(attrs.get((None, 'stroke_width'), "1"))
        self.aLayer = layer_class(title,
                                  self.theSession.OpenShapefile(filename),
                                  fill = fill, stroke = stroke,
                                  lineWidth = stroke_width)

    def end_layer(self, name, qname):
        self.aMap.AddLayer(self.aLayer)

    def start_classification(self, name, qname, attrs):
        field = attrs.get((None, 'field'), None)

        fieldType = attrs.get((None, 'field_type'), None)
        dbFieldType = self.aLayer.GetFieldType(field)

        if fieldType != dbFieldType:
            raise ValueError(_("xml field type differs from database!"))

        # setup conversion routines depending on the kind of data
        # we will be seeing later on
        if fieldType == FIELDTYPE_STRING:
            self.conv = str
        elif fieldType == FIELDTYPE_INT:
            self.conv = lambda p: int(float(p))
        elif fieldType == FIELDTYPE_DOUBLE:
            self.conv = float

        self.aLayer.GetClassification().SetField(field)


    def end_classification(self, name, qname): 
        pass

    def start_clnull(self, name, qname, attrs):
        self.cl_group = ClassGroupDefault()
        self.cl_group.SetLabel(attrs.get((None, 'label'), ""))
        self.cl_prop = ClassGroupProperties()

    def end_clnull(self, name, qname):
        self.cl_group.SetProperties(self.cl_prop)
        self.aLayer.GetClassification().SetDefaultGroup(self.cl_group)
        del self.cl_group, self.cl_prop

    def start_clpoint(self, name, qname, attrs):
        attrib_value = attrs.get((None, 'value'), "0")

        #try:
            #value  = Str2Num(attrib_value)
        #except:
            #value  = attrib_value

        value = self.conv(attrib_value)

        self.cl_group = ClassGroupSingleton(value)
        self.cl_group.SetLabel(attrs.get((None, 'label'), ""))
        self.cl_prop = ClassGroupProperties()


    def end_clpoint(self, name, qname):
        self.cl_group.SetProperties(self.cl_prop)
        self.aLayer.GetClassification().AppendGroup(self.cl_group)
        del self.cl_group, self.cl_prop

    def start_clrange(self, name, qname, attrs):

        try:
            min = self.conv(attrs.get((None, 'min'), "0"))
            max = self.conv(attrs.get((None, 'max'), "0"))
            #min = Str2Num(attrs.get((None, 'min'), "0"))
            #max = Str2Num(attrs.get((None, 'max'), "0"))
        except ValueError:
            raise ValueError(_("Classification range is not a number!"))

        self.cl_group = ClassGroupRange(min, max)
        self.cl_group.SetLabel(attrs.get((None, 'label'), ""))
        self.cl_prop = ClassGroupProperties()


    def end_clrange(self, name, qname):
        self.cl_group.SetProperties(self.cl_prop)
        self.aLayer.GetClassification().AppendGroup(self.cl_group)
        del self.cl_group, self.cl_prop

    def start_cldata(self, name, qname, attrs):
        self.cl_prop.SetLineColor(
            parse_color(attrs.get((None, 'stroke'), "None")))
        self.cl_prop.SetLineWidth(
            int(attrs.get((None, 'stroke_width'), "0")))
        self.cl_prop.SetFill(parse_color(attrs.get((None, 'fill'), "None")))

    def end_cldata(self, name, qname):
        pass

    def start_table(self, name, qname, attrs):
        #print "table title: %s" % attrs.get('title', None)
        pass

    def end_table(self, name, qname):
        pass

    def start_labellayer(self, name, qname, attrs):
        self.aLayer = self.aMap.LabelLayer()

    def start_label(self, name, qname, attrs):
        x = float(attrs[(None, 'x')])
        y = float(attrs[(None, 'y')])
        text = attrs[(None, 'text')]
        halign = attrs[(None, 'halign')]
        valign = attrs[(None, 'valign')]
        self.aLayer.AddLabel(x, y, text, halign = halign, valign = valign)

    def characters(self, chars):
        pass


def load_session(filename):
    """Load a Thuban session from the file object file"""

    handler = SessionLoader()
    handler.read(filename)

    session = handler.theSession
    # Newly loaded session aren't modified
    session.UnsetModified()

    return session

1	# Copyright (C) 2001, 2002, 2003 by Intevation GmbH
2	# Authors:
3	# Jan-Oliver Wagner <[email protected]>
4	# Bernhard Herzog <[email protected]>
5	# Jonathan Coles <[email protected]>
6	#
7	# This program is free software under the GPL (>=v2)
8	# Read the file COPYING coming with GRASS for details.
9
10	"""
11	Parser for thuban session files.
12	"""
13
14	__version__ = "$Revision$"
15
16	import string, os
17
18	import xml.sax
19	import xml.sax.handler
20	from xml.sax import make_parser, ErrorHandler, SAXNotRecognizedException
21
22	from Thuban import _
23	from Thuban.common import *
24
25	from Thuban.Model.table import FIELDTYPE_INT, FIELDTYPE_DOUBLE, \
26	FIELDTYPE_STRING
27
28	from Thuban.Model.session import Session
29	from Thuban.Model.map import Map
30	from Thuban.Model.layer import Layer
31	from Thuban.Model.color import Color
32	from Thuban.Model.proj import Projection
33	from Thuban.Model.classification import Classification, \
34	ClassGroupDefault, ClassGroupSingleton, ClassGroupRange, ClassGroupMap, \
35	ClassGroupProperties
36
37
38	def parse_color(color):
39	"""Return the color object for the string color.
40
41	Color may be either 'None' or of the form '#RRGGBB' in the usual
42	HTML color notation
43	"""
44	color = string.strip(color)
45	if color == "None":
46	result = Color.Transparent
47	elif color[0] == '#':
48	if len(color) == 7:
49	r = string.atoi(color[1:3], 16) / 255.0
50	g = string.atoi(color[3:5], 16) / 255.0
51	b = string.atoi(color[5:7], 16) / 255.0
52	result = Color(r, g, b)
53	else:
54	raise ValueError(_("Invalid hexadecimal color specification %s")
55	% color)
56	else:
57	raise ValueError(_("Invalid color specification %s") % color)
58	return result
59
60
61	class XMLReader(xml.sax.handler.ContentHandler):
62
63	# Dictionary mapping element names (or (URI, element name) pairs for
64	# documents using namespaces) to method names. The methods should
65	# accept the same parameters as the startElement (or startElementNS)
66	# methods. The start_dispatcher is used by the default startElement
67	# and startElementNS methods to call a method for the open tag of an
68	# element.
69	start_dispatcher = {}
70
71	# end_dispatcher works just like start_dispatcher but it's used by
72	# endElement and endElementNS. The method whose names it maps to
73	# should accept the same parameters as endElement and endElementNS.
74	end_dispatcher = {}
75
76
77	def __init__(self):
78	self.chars = ''
79	self.__parser = None
80	self.__directory = ""
81	self.__dispatchers = {}
82
83	def read(self, file_or_filename):
84
85	if hasattr(file_or_filename, "read"):
86	# it's a file object
87	self.__directory = ""
88	self.__file = file_or_filename
89	else:
90	filename = file_or_filename
91	self.__directory = os.path.dirname(filename)
92	self.__file = open(filename)
93
94	if self.__parser is None:
95	self.__parser = make_parser()
96	self.__parser.setContentHandler(self)
97	self.__parser.setErrorHandler(ErrorHandler())
98	self.__parser.setFeature(xml.sax.handler.feature_namespaces, 1)
99
100	#
101	# Well, this isn't pretty, but it appears that if you
102	# use Python 2.2 without the site-package _xmlplus then
103	# the following will fail, and without them it will work.
104	# However, if you do have the site-package and you don't
105	# call these functions, the reader raises an exception
106	#
107	# The reason we set these to 0 in the first place is
108	# because there is an unresolved issue with external
109	# entities causing an exception in the reader
110	#
111	try:
112	self.__parser.setFeature(xml.sax.handler.feature_validation,0)
113	self.__parser.setFeature(xml.sax.handler.feature_external_ges,0)
114	self.__parser.setFeature(xml.sax.handler.feature_external_pes,0)
115	except SAXNotRecognizedException:
116	pass
117
118	self.__parser.parse(self.__file)
119
120	self.close()
121
122	def close(self):
123	self.__file.close()
124
125	def GetFileName(self):
126	if hasattr(self.__file, "name"):
127	return self.__file.name
128
129	return ""
130
131	def GetDirectory(self):
132	return self.__directory
133
134
135	def AddDispatchers(self, dict):
136	"""Add the function names that should be used to process XML tags.
137
138	dict -- a dictionary whose keys are XML tag strings and whose values
139	are pairs of strings such that the first string is
140	the name of the function that should be called when the
141	XML tag opens and the second string is the name of the
142	function that should be called when the XML tag closes.
143	If a pair element is None, no function is called.
144	"""
145
146	self.__dispatchers.update(dict)
147
148	def startElementNS(self, name, qname, attrs):
149	"""Call the method given for name in self.start_dispatcher
150	"""
151	if name[0] is None:
152	method_name = self.__dispatchers.get(name[1])
153	else:
154	# Dispatch with namespace
155	method_name = self.__dispatchers.get(name)
156	if method_name is not None and method_name[0] is not None:
157	getattr(self, method_name[0])(name, qname, attrs)
158
159	def endElementNS(self, name, qname):
160	"""Call the method given for name in self.end_dispatcher
161	"""
162	if name[0] is None:
163	method_name = self.__dispatchers.get(name[1])
164	else:
165	# Dispatch with namespace
166	method_name = self.__dispatchers.get(name)
167	if method_name is not None and method_name[1] is not None:
168	getattr(self, method_name[1])(name, qname)
169
170	class SessionLoader(XMLReader):
171
172	def __init__(self):
173	"""Inititialize the Sax handler."""
174	XMLReader.__init__(self)
175
176	self.theSession = None
177	self.aMap = None
178	self.aLayer = None
179
180	XMLReader.AddDispatchers(self,
181	{'session' : ("start_session", "end_session"),
182	'map' : ("start_map", "end_map"),
183	'projection' : ("start_projection", "end_projection"),
184	'parameter' : ("start_parameter", None),
185	'layer' : ("start_layer", "end_layer"),
186	'classification': ("start_classification", "end_classification"),
187	'clnull' : ("start_clnull", "end_clnull"),
188	'clpoint' : ("start_clpoint", "end_clpoint"),
189	'clrange' : ("start_clrange", "end_clrange"),
190	'cldata' : ("start_cldata", "end_cldata"),
191	'table' : ("start_table", "end_table"),
192	'labellayer' : ("start_labellayer", None),
193	'label' : ("start_label", None)})
194
195	def start_session(self, name, qname, attrs):
196	self.theSession = Session(attrs.get((None, 'title'), None))
197
198	def end_session(self, name, qname):
199	pass
200
201	def start_map(self, name, qname, attrs):
202	"""Start a map."""
203	self.aMap = Map(attrs.get((None, 'title'), None))
204
205	def end_map(self, name, qname):
206	self.theSession.AddMap(self.aMap)
207
208	def start_projection(self, name, qname, attrs):
209	self.ProjectionParams = [ ]
210
211	def end_projection(self, name, qname):
212	self.aMap.SetProjection(Projection(self.ProjectionParams))
213
214	def start_parameter(self, name, qname, attrs):
215	s = attrs.get((None, 'value'))
216	s = str(s) # we can't handle unicode in proj
217	self.ProjectionParams.append(s)
218
219	def start_layer(self, name, qname, attrs, layer_class = Layer):
220	"""Start a layer
221
222	Instantiate a layer of class layer_class from the attributes in
223	attrs which may be a dictionary as well as the normal SAX attrs
224	object and bind it to self.aLayer.
225	"""
226	title = attrs.get((None, 'title'), "")
227	filename = attrs.get((None, 'filename'), "")
228	filename = os.path.join(self.GetDirectory(), filename)
229	fill = parse_color(attrs.get((None, 'fill'), "None"))
230	stroke = parse_color(attrs.get((None, 'stroke'), "#000000"))
231	stroke_width = int(attrs.get((None, 'stroke_width'), "1"))
232	self.aLayer = layer_class(title,
233	self.theSession.OpenShapefile(filename),
234	fill = fill, stroke = stroke,
235	lineWidth = stroke_width)
236
237	def end_layer(self, name, qname):
238	self.aMap.AddLayer(self.aLayer)
239
240	def start_classification(self, name, qname, attrs):
241	field = attrs.get((None, 'field'), None)
242
243	fieldType = attrs.get((None, 'field_type'), None)
244	dbFieldType = self.aLayer.GetFieldType(field)
245
246	if fieldType != dbFieldType:
247	raise ValueError(_("xml field type differs from database!"))
248
249	# setup conversion routines depending on the kind of data
250	# we will be seeing later on
251	if fieldType == FIELDTYPE_STRING:
252	self.conv = str
253	elif fieldType == FIELDTYPE_INT:
254	self.conv = lambda p: int(float(p))
255	elif fieldType == FIELDTYPE_DOUBLE:
256	self.conv = float
257
258	self.aLayer.GetClassification().SetField(field)
259
260
261	def end_classification(self, name, qname):
262	pass
263
264	def start_clnull(self, name, qname, attrs):
265	self.cl_group = ClassGroupDefault()
266	self.cl_group.SetLabel(attrs.get((None, 'label'), ""))
267	self.cl_prop = ClassGroupProperties()
268
269	def end_clnull(self, name, qname):
270	self.cl_group.SetProperties(self.cl_prop)
271	self.aLayer.GetClassification().SetDefaultGroup(self.cl_group)
272	del self.cl_group, self.cl_prop
273
274	def start_clpoint(self, name, qname, attrs):
275	attrib_value = attrs.get((None, 'value'), "0")
276
277	#try:
278	#value = Str2Num(attrib_value)
279	#except:
280	#value = attrib_value
281
282	value = self.conv(attrib_value)
283
284	self.cl_group = ClassGroupSingleton(value)
285	self.cl_group.SetLabel(attrs.get((None, 'label'), ""))
286	self.cl_prop = ClassGroupProperties()
287
288
289	def end_clpoint(self, name, qname):
290	self.cl_group.SetProperties(self.cl_prop)
291	self.aLayer.GetClassification().AppendGroup(self.cl_group)
292	del self.cl_group, self.cl_prop
293
294	def start_clrange(self, name, qname, attrs):
295
296	try:
297	min = self.conv(attrs.get((None, 'min'), "0"))
298	max = self.conv(attrs.get((None, 'max'), "0"))
299	#min = Str2Num(attrs.get((None, 'min'), "0"))
300	#max = Str2Num(attrs.get((None, 'max'), "0"))
301	except ValueError:
302	raise ValueError(_("Classification range is not a number!"))
303
304	self.cl_group = ClassGroupRange(min, max)
305	self.cl_group.SetLabel(attrs.get((None, 'label'), ""))
306	self.cl_prop = ClassGroupProperties()
307
308
309	def end_clrange(self, name, qname):
310	self.cl_group.SetProperties(self.cl_prop)
311	self.aLayer.GetClassification().AppendGroup(self.cl_group)
312	del self.cl_group, self.cl_prop
313
314	def start_cldata(self, name, qname, attrs):
315	self.cl_prop.SetLineColor(
316	parse_color(attrs.get((None, 'stroke'), "None")))
317	self.cl_prop.SetLineWidth(
318	int(attrs.get((None, 'stroke_width'), "0")))
319	self.cl_prop.SetFill(parse_color(attrs.get((None, 'fill'), "None")))
320
321	def end_cldata(self, name, qname):
322	pass
323
324	def start_table(self, name, qname, attrs):
325	#print "table title: %s" % attrs.get('title', None)
326	pass
327
328	def end_table(self, name, qname):
329	pass
330
331	def start_labellayer(self, name, qname, attrs):
332	self.aLayer = self.aMap.LabelLayer()
333
334	def start_label(self, name, qname, attrs):
335	x = float(attrs[(None, 'x')])
336	y = float(attrs[(None, 'y')])
337	text = attrs[(None, 'text')]
338	halign = attrs[(None, 'halign')]
339	valign = attrs[(None, 'valign')]
340	self.aLayer.AddLabel(x, y, text, halign = halign, valign = valign)
341
342	def characters(self, chars):
343	pass
344
345
346	def load_session(filename):
347	"""Load a Thuban session from the file object file"""
348
349	handler = SessionLoader()
350	handler.read(filename)
351
352	session = handler.theSession
353	# Newly loaded session aren't modified
354	session.UnsetModified()
355
356	return session
357
Name	Value
svn:eol-style	native
svn:keywords	Author Date Id Revision