Thuban/Model/save.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 Thuban for details.

"""
Functions to save a session to a file
"""

__version__ = "$Revision$"

import os

import Thuban.Lib.fileutil

from Thuban.Model.color import Color 
from Thuban.Model.layer import Layer, RasterLayer

from Thuban.Model.classification import \
    ClassGroupDefault, ClassGroupSingleton, ClassGroupRange, ClassGroupMap

from Thuban.Model.xmlwriter import XMLWriter

def relative_filename(dir, filename):
    """Return a filename relative to dir for the absolute file name absname.

    This is almost the same as the function in fileutil, except that dir
    can be an empty string in which case filename will be returned
    unchanged.
    """
    if dir:
        return Thuban.Lib.fileutil.relative_filename(dir, filename)
    else:
        return filename

class SessionSaver(XMLWriter):

    """Class to serialize a session into an XML file.

    Applications built on top of Thuban may derive from this class and
    override or extend the methods to save additional information. This
    additional information should take the form of additional attributes
    or elements whose names are prefixed with a namespace. To define a
    namespace derived classes should extend the write_session method to
    pass the namespaces to the default implementation.
    """


    def __init__(self, session):
        XMLWriter.__init__(self)
        self.session = session

    def write(self, file_or_filename):
        XMLWriter.write(self, file_or_filename)

        self.write_header("session", "thuban.dtd")
        self.write_session(self.session)
        self.close()

    def write_session(self, session, attrs = None, namespaces = ()):
        """Write the session and its contents

        By default, write a session element with the title attribute and
        call write_map for each map contained in the session.

        The optional argument attrs is for additional attributes and, if
        given, should be a mapping from attribute names to attribute
        values. The values should not be XML-escaped yet.

        The optional argument namespaces, if given, should be a sequence
        of (name, URI) pairs. The namespaces are written as namespace
        attributes into the session element. This is mainly useful for
        derived classes that need to store additional information in a
        thuban session file.
        """
        if attrs is None:
            attrs = {}
        attrs["title"] = session.title
        for name, uri in namespaces:
            attrs["xmlns:" + name] = uri
        self.open_element("session", attrs)
        for map in session.Maps():
            self.write_map(map)
        self.close_element("session")

    def write_map(self, map):
        """Write the map and its contents.

        By default, write a map element element with the title
        attribute, call write_projection to write the projection
        element, call write_layer for each layer contained in the map
        and finally call write_label_layer to write the label layer.
        """
        self.open_element('map title="%s"' % self.encode(map.title))
        self.write_projection(map.projection)
        for layer in map.Layers():
            self.write_layer(layer)
        self.write_label_layer(map.LabelLayer())
        self.close_element('map')

    def write_projection(self, projection):
        """Write the projection.
        """
        if projection and len(projection.params) > 0:
            self.open_element("projection", {"name": projection.GetName()})
            for param in projection.params:
                self.write_element('parameter value="%s"' % 
                                   self.encode(param))
            self.close_element("projection")

    def write_layer(self, layer, attrs = None):
        """Write the layer.

        The optional argument attrs is for additional attributes and, if
        given, should be a mapping from attribute names to attribute
        values. The values should not be XML-escaped yet.
        """

        if attrs is None:
            attrs = {}

        attrs["title"]   = layer.title
        attrs["visible"] = ("false", "true")[int(layer.Visible())]

        if isinstance(layer, Layer):
            attrs["filename"] = relative_filename(self.dir,
                                                layer.ShapeStore().FileName())

            lc = layer.GetClassification()
            attrs["stroke"]       = lc.GetDefaultLineColor().hex()
            attrs["stroke_width"] = str(lc.GetDefaultLineWidth())
            attrs["fill"]         = lc.GetDefaultFill().hex()

            self.open_element("layer", attrs)
            self.write_projection(layer.GetProjection())
            self.write_classification(layer)
            self.close_element("layer")

        elif isinstance(layer, RasterLayer):
            attrs["filename"] = relative_filename(self.dir, layer.filename)
            self.open_element("rasterlayer", attrs)
            self.write_projection(layer.GetProjection())
            self.close_element("rasterlayer")

    def write_classification(self, layer, attrs = None):
        """Write Classification information."""

        if attrs is None:
            attrs = {}

        lc = layer.GetClassification()

        field = lc.GetField()
 
        #
        # there isn't a classification of anything so do nothing
        #
        if field is None: return

        attrs["field"] = field
        attrs["field_type"] = str(lc.GetFieldType())
        self.open_element("classification", attrs)

        for g in lc:
            if isinstance(g, ClassGroupDefault):
                open_el  = 'clnull label="%s"' % self.encode(g.GetLabel())
                close_el = 'clnull'
            elif isinstance(g, ClassGroupSingleton): 
                open_el  = 'clpoint label="%s" value="%s"' \
                           % (self.encode(g.GetLabel()), str(g.GetValue()))
                close_el = 'clpoint'
            elif isinstance(g, ClassGroupRange):
                open_el  = 'clrange label="%s" range="%s"' \
                          % (self.encode(g.GetLabel()), str(g.GetRange()))
                close_el = 'clrange'
            else:
                assert False, _("Unsupported group type in classification")
                continue

            data = g.GetProperties()
            dict = {'stroke'      : data.GetLineColor().hex(),
                    'stroke_width': str(data.GetLineWidth()),
                    'fill'        : data.GetFill().hex()}

            self.open_element(open_el)
            self.write_element("cldata", dict)
            self.close_element(close_el)

        self.close_element("classification")

    def write_label_layer(self, layer):
        """Write the label layer.
        """
        labels = layer.Labels()
        if labels:
            self.open_element('labellayer')
            for label in labels:
                self.write_element(('label x="%g" y="%g" text="%s"'
                                    ' halign="%s" valign="%s"')
                                % (label.x, label.y, 
                                   self.encode(label.text), 
                                   label.halign,
                                   label.valign))
            self.close_element('labellayer')


def save_session(session, file, saver_class = None):
    """Save the session session to a file.

    The file argument may either be a filename or an open file object.

    The optional argument saver_class is the class to use to serialize
    the session. By default or if it's None, the saver class will be
    SessionSaver.

    If writing the session is successful call the session's
    UnsetModified method
    """
    if saver_class is None:
        saver_class = SessionSaver
    saver = saver_class(session)
    saver.write(file)

    # after a successful save consider the session unmodified.
    session.UnsetModified()
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 Thuban for details.
9
10	"""
11	Functions to save a session to a file
12	"""
13
14	__version__ = "$Revision$"
15
16	import os
17
18	import Thuban.Lib.fileutil
19
20	from Thuban.Model.color import Color
21	from Thuban.Model.layer import Layer, RasterLayer
22
23	from Thuban.Model.classification import \
24	ClassGroupDefault, ClassGroupSingleton, ClassGroupRange, ClassGroupMap
25
26	from Thuban.Model.xmlwriter import XMLWriter
27
28	def relative_filename(dir, filename):
29	"""Return a filename relative to dir for the absolute file name absname.
30
31	This is almost the same as the function in fileutil, except that dir
32	can be an empty string in which case filename will be returned
33	unchanged.
34	"""
35	if dir:
36	return Thuban.Lib.fileutil.relative_filename(dir, filename)
37	else:
38	return filename
39
40	class SessionSaver(XMLWriter):
41
42	"""Class to serialize a session into an XML file.
43
44	Applications built on top of Thuban may derive from this class and
45	override or extend the methods to save additional information. This
46	additional information should take the form of additional attributes
47	or elements whose names are prefixed with a namespace. To define a
48	namespace derived classes should extend the write_session method to
49	pass the namespaces to the default implementation.
50	"""
51
52
53	def __init__(self, session):
54	XMLWriter.__init__(self)
55	self.session = session
56
57	def write(self, file_or_filename):
58	XMLWriter.write(self, file_or_filename)
59
60	self.write_header("session", "thuban.dtd")
61	self.write_session(self.session)
62	self.close()
63
64	def write_session(self, session, attrs = None, namespaces = ()):
65	"""Write the session and its contents
66
67	By default, write a session element with the title attribute and
68	call write_map for each map contained in the session.
69
70	The optional argument attrs is for additional attributes and, if
71	given, should be a mapping from attribute names to attribute
72	values. The values should not be XML-escaped yet.
73
74	The optional argument namespaces, if given, should be a sequence
75	of (name, URI) pairs. The namespaces are written as namespace
76	attributes into the session element. This is mainly useful for
77	derived classes that need to store additional information in a
78	thuban session file.
79	"""
80	if attrs is None:
81	attrs = {}
82	attrs["title"] = session.title
83	for name, uri in namespaces:
84	attrs["xmlns:" + name] = uri
85	self.open_element("session", attrs)
86	for map in session.Maps():
87	self.write_map(map)
88	self.close_element("session")
89
90	def write_map(self, map):
91	"""Write the map and its contents.
92
93	By default, write a map element element with the title
94	attribute, call write_projection to write the projection
95	element, call write_layer for each layer contained in the map
96	and finally call write_label_layer to write the label layer.
97	"""
98	self.open_element('map title="%s"' % self.encode(map.title))
99	self.write_projection(map.projection)
100	for layer in map.Layers():
101	self.write_layer(layer)
102	self.write_label_layer(map.LabelLayer())
103	self.close_element('map')
104
105	def write_projection(self, projection):
106	"""Write the projection.
107	"""
108	if projection and len(projection.params) > 0:
109	self.open_element("projection", {"name": projection.GetName()})
110	for param in projection.params:
111	self.write_element('parameter value="%s"' %
112	self.encode(param))
113	self.close_element("projection")
114
115	def write_layer(self, layer, attrs = None):
116	"""Write the layer.
117
118	The optional argument attrs is for additional attributes and, if
119	given, should be a mapping from attribute names to attribute
120	values. The values should not be XML-escaped yet.
121	"""
122
123	if attrs is None:
124	attrs = {}
125
126	attrs["title"] = layer.title
127	attrs["visible"] = ("false", "true")[int(layer.Visible())]
128
129	if isinstance(layer, Layer):
130	attrs["filename"] = relative_filename(self.dir,
131	layer.ShapeStore().FileName())
132
133	lc = layer.GetClassification()
134	attrs["stroke"] = lc.GetDefaultLineColor().hex()
135	attrs["stroke_width"] = str(lc.GetDefaultLineWidth())
136	attrs["fill"] = lc.GetDefaultFill().hex()
137
138	self.open_element("layer", attrs)
139	self.write_projection(layer.GetProjection())
140	self.write_classification(layer)
141	self.close_element("layer")
142
143	elif isinstance(layer, RasterLayer):
144	attrs["filename"] = relative_filename(self.dir, layer.filename)
145	self.open_element("rasterlayer", attrs)
146	self.write_projection(layer.GetProjection())
147	self.close_element("rasterlayer")
148
149	def write_classification(self, layer, attrs = None):
150	"""Write Classification information."""
151
152	if attrs is None:
153	attrs = {}
154
155	lc = layer.GetClassification()
156
157	field = lc.GetField()
158
159	#
160	# there isn't a classification of anything so do nothing
161	#
162	if field is None: return
163
164	attrs["field"] = field
165	attrs["field_type"] = str(lc.GetFieldType())
166	self.open_element("classification", attrs)
167
168	for g in lc:
169	if isinstance(g, ClassGroupDefault):
170	open_el = 'clnull label="%s"' % self.encode(g.GetLabel())
171	close_el = 'clnull'
172	elif isinstance(g, ClassGroupSingleton):
173	open_el = 'clpoint label="%s" value="%s"' \
174	% (self.encode(g.GetLabel()), str(g.GetValue()))
175	close_el = 'clpoint'
176	elif isinstance(g, ClassGroupRange):
177	open_el = 'clrange label="%s" range="%s"' \
178	% (self.encode(g.GetLabel()), str(g.GetRange()))
179	close_el = 'clrange'
180	else:
181	assert False, _("Unsupported group type in classification")
182	continue
183
184	data = g.GetProperties()
185	dict = {'stroke' : data.GetLineColor().hex(),
186	'stroke_width': str(data.GetLineWidth()),
187	'fill' : data.GetFill().hex()}
188
189	self.open_element(open_el)
190	self.write_element("cldata", dict)
191	self.close_element(close_el)
192
193	self.close_element("classification")
194
195	def write_label_layer(self, layer):
196	"""Write the label layer.
197	"""
198	labels = layer.Labels()
199	if labels:
200	self.open_element('labellayer')
201	for label in labels:
202	self.write_element(('label x="%g" y="%g" text="%s"'
203	' halign="%s" valign="%s"')
204	% (label.x, label.y,
205	self.encode(label.text),
206	label.halign,
207	label.valign))
208	self.close_element('labellayer')
209
210
211
212	def save_session(session, file, saver_class = None):
213	"""Save the session session to a file.
214
215	The file argument may either be a filename or an open file object.
216
217	The optional argument saver_class is the class to use to serialize
218	the session. By default or if it's None, the saver class will be
219	SessionSaver.
220
221	If writing the session is successful call the session's
222	UnsetModified method
223	"""
224	if saver_class is None:
225	saver_class = SessionSaver
226	saver = saver_class(session)
227	saver.write(file)
228
229	# after a successful save consider the session unmodified.
230	session.UnsetModified()
Name	Value
svn:eol-style	native
svn:keywords	Author Date Id Revision