Thuban/Model/load.py

# Copyright (C) 2001, 2002 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 sys, 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, 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 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 sys, 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, filename, fill = fill,
233	stroke = stroke, lineWidth = stroke_width)
234
235	def end_layer(self, name, qname):
236	self.aMap.AddLayer(self.aLayer)
237
238	def start_classification(self, name, qname, attrs):
239	field = attrs.get((None, 'field'), None)
240
241	fieldType = attrs.get((None, 'field_type'), None)
242	dbFieldType = self.aLayer.GetFieldType(field)
243
244	if fieldType != dbFieldType:
245	raise ValueError(_("xml field type differs from database!"))
246
247	# setup conversion routines depending on the kind of data
248	# we will be seeing later on
249	if fieldType == FIELDTYPE_STRING:
250	self.conv = str
251	elif fieldType == FIELDTYPE_INT:
252	self.conv = lambda p: int(float(p))
253	elif fieldType == FIELDTYPE_DOUBLE:
254	self.conv = float
255
256	self.aLayer.GetClassification().SetField(field)
257
258
259	def end_classification(self, name, qname):
260	pass
261
262	def start_clnull(self, name, qname, attrs):
263	self.cl_group = ClassGroupDefault()
264	self.cl_group.SetLabel(attrs.get((None, 'label'), ""))
265	self.cl_prop = ClassGroupProperties()
266
267	def end_clnull(self, name, qname):
268	self.cl_group.SetProperties(self.cl_prop)
269	self.aLayer.GetClassification().SetDefaultGroup(self.cl_group)
270	del self.cl_group, self.cl_prop
271
272	def start_clpoint(self, name, qname, attrs):
273	attrib_value = attrs.get((None, 'value'), "0")
274
275	#try:
276	#value = Str2Num(attrib_value)
277	#except:
278	#value = attrib_value
279
280	value = self.conv(attrib_value)
281
282	self.cl_group = ClassGroupSingleton(value)
283	self.cl_group.SetLabel(attrs.get((None, 'label'), ""))
284	self.cl_prop = ClassGroupProperties()
285
286
287	def end_clpoint(self, name, qname):
288	self.cl_group.SetProperties(self.cl_prop)
289	self.aLayer.GetClassification().AppendGroup(self.cl_group)
290	del self.cl_group, self.cl_prop
291
292	def start_clrange(self, name, qname, attrs):
293
294	try:
295	min = self.conv(attrs.get((None, 'min'), "0"))
296	max = self.conv(attrs.get((None, 'max'), "0"))
297	#min = Str2Num(attrs.get((None, 'min'), "0"))
298	#max = Str2Num(attrs.get((None, 'max'), "0"))
299	except ValueError:
300	raise ValueError(_("Classification range is not a number!"))
301
302	self.cl_group = ClassGroupRange(min, max)
303	self.cl_group.SetLabel(attrs.get((None, 'label'), ""))
304	self.cl_prop = ClassGroupProperties()
305
306
307	def end_clrange(self, name, qname):
308	self.cl_group.SetProperties(self.cl_prop)
309	self.aLayer.GetClassification().AppendGroup(self.cl_group)
310	del self.cl_group, self.cl_prop
311
312	def start_cldata(self, name, qname, attrs):
313	self.cl_prop.SetLineColor(
314	parse_color(attrs.get((None, 'stroke'), "None")))
315	self.cl_prop.SetLineWidth(
316	int(attrs.get((None, 'stroke_width'), "0")))
317	self.cl_prop.SetFill(parse_color(attrs.get((None, 'fill'), "None")))
318
319	def end_cldata(self, name, qname):
320	pass
321
322	def start_table(self, name, qname, attrs):
323	#print "table title: %s" % attrs.get('title', None)
324	pass
325
326	def end_table(self, name, qname):
327	pass
328
329	def start_labellayer(self, name, qname, attrs):
330	self.aLayer = self.aMap.LabelLayer()
331
332	def start_label(self, name, qname, attrs):
333	x = float(attrs[(None, 'x')])
334	y = float(attrs[(None, 'y')])
335	text = attrs[(None, 'text')]
336	halign = attrs[(None, 'halign')]
337	valign = attrs[(None, 'valign')]
338	self.aLayer.AddLabel(x, y, text, halign = halign, valign = valign)
339
340	def characters(self, chars):
341	pass
342
343
344	def load_session(filename):
345	"""Load a Thuban session from the file object file"""
346
347	handler = SessionLoader()
348	handler.read(filename)
349
350	session = handler.theSession
351	# Newly loaded session aren't modified
352	session.UnsetModified()
353
354	return session
355
Name	Value
svn:eol-style	native
svn:keywords	Author Date Id Revision