Changeset 3573 for TI05-delivery/ows_framework

Timestamp:

10/03/08 16:40:33 (12 years ago)

Author:

spascoe

Message:

GetLegend? support

Location:

TI05-delivery/ows_framework/branches/ows_framework-refactor/ows_common/ows_common

Files:

• pylons/templates/wms_capabilities_1_1_1.xml (modified) (1 diff)
• pylons/wms_controller.py (modified) (5 diffs)
• service/wms_iface.py (modified) (2 diffs)

TI05-delivery/ows_framework/branches/ows_framework-refactor/ows_common/ows_common/pylons/templates/wms_capabilities_1_1_1.xml

@@ -58 +58 @@
     <!-- TODO DataURL from metadata -->
     <!-- TODO MetadataURL from metadata -->
-    <!-- TODO Style -->
+    
+    <!--!NOTE: this is an ad-hoc implementation not using the ows_common.model classes
+         TODO: fixme -->
+    <Style>
+      <Name>default</Name>
+      <Title>Default</Title>
+      <LegendURL width="${ds.legendSize[0]}" height="${ds.legendSize[1]}">
+        <Format py:for="f in ds.legendFormats" py:content="f"/>
+        <OnlineResource xmlns:xlink="http://www.w3.org/1999/xlink" xlink:type="simple" 
+                        xlink:href="${h.url_for(qualified=True, action='index')}?request=GetLegend&amp;layers=${ds.identifier}"/>
+      </LegendURL>
+    </Style>
+
     <!-- TODO ScaleHint -->
 

TI05-delivery/ows_framework/branches/ows_framework-refactor/ows_common/ows_common/pylons/wms_controller.py

@@ -44 +44 @@
     service = 'WMS'
     owsOperations = ows_controller.OWSController.owsOperations + ['GetMap', 'GetContext',
+                                                                  'GetLegend',
                                                                   'GetInfo']
     validVersions = ['1.1.1']
@@ -75 +76 @@
         """
         ows_controller.addOperation('GetMap', formats=self._pilImageFormats.keys())
+        ows_controller.addOperation('GetContext')
+        ows_controller.addOperation('GetLegend',
+                                    formats=self._pilImageFormats.keys())
         ows_controller.addOperation('GetInfo')
         log.debug('Loading capabilities contents')
@@ -101 +105 @@
                                    dimensions=dims)
 
+            # Stuff that should go in the capabilities tree eventually
+            ds.legendSize = layer.legendSize
+            ds.legendFormats = self._pilImageFormats.keys()
+
             c.capabilities.contents.datasetSummaries.append(ds)
 
+
+
+    def _getLayerParam(self):
+        """
+        Retrieve the layers parameter enforcing the rule of only
+        selecting one layer.
+
+        """
+        layerName = self.getOwsParam('layers')
+
+        # Select the first layer if several are requested.
+        # This plays nicer with mapClient.
+        if ',' in layerName:
+            layerName = layerName.split(',')[0]
+            #raise InvalidParameterValue(
+            #    'Multi-layer GetMap requests are not supported', 'layers')
+        try:
+            layerObj = self.layers[layerName]
+        except KeyError:
+            raise InvalidParameterValue('Layer %s not found' % layerName, 'layers')
+
+        return layerName, layerObj
+
+    def _getFormatParam(self):
+        format = self.getOwsParam('format', default='image/png')
+        if format not in self._pilImageFormats:
+            raise InvalidParameterValue(
+                'Format %s not supported' % format, 'format')
+
+        return format
+    
     #-------------------------------------------------------------------------
     # OWS Operation methods
@@ -118 +157 @@
 
         # Layer handling
-        layerName = self.getOwsParam('layers')
-        if ',' in layerName:
-            raise InvalidParameterValue(
-                'Multi-layer GetMap requests are not supported', 'layers')
-        try:
-            layerObj = self.layers[layerName]
-        except KeyError:
-            raise InvalidParameterValue('Layer %s not found' % layerName, 'layers')
-
+        layerName, layerObj = self._getLayerParam()
         
         # Coordinate parameters
@@ -239 +270 @@
         return t.generate(c=c).render()
 
+    def GetLegend(self):
+        """
+        Return an image of the legend.
+
+        """
+        # Parameters
+        layerName, layerObj = self._getLayerParam()
+        format = self._getFormatParam()
+
+        img = layerObj.getLegendImage()
+
+        buf = StringIO()
+        img.save(buf, self._pilImageFormats[format])
+
+        response.headers['Content-Type'] = format
+        response.write(buf.getvalue())
+
 
     def GetInfo(self):

TI05-delivery/ows_framework/branches/ows_framework-refactor/ows_common/ows_common/service/wms_iface.py

@@ -40 +40 @@
     @ivar units: A string describing the units.
     @ivar crss: A sequence of SRS/CRSs supported by this layer.
+    @ivar legendSize: (width, height) in pixels of legend.
 
     @todo: Do we need minValue/maxValue?
@@ -82 +83 @@
         raise NotImplementedError
 
+    def getLegendImage(self, orientation='vertical', renderOpts={}):
+        """
+        Create an image of the colourbar for this layer.
+        
+        @param orientation: Either 'vertical' or 'horizontal'
+        @return: A PIL image
+
+        """
+        raise NotImplementedError
 
 class IDimension(object):