gis: Added KML sitemap support.

git-svn-id: http://code.djangoproject.com/svn/django/branches/gis@5751 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/gis/db/models/manager.py

@@ -6,3 +6,6 @@ class GeoManager(Manager):
 
     def get_query_set(self):
         return GeoQuerySet(model=self.model)
+
+    def kml(self, field_name):
+        return self.get_query_set().kml(field_name)

django/contrib/gis/db/models/query.py

@@ -1,5 +1,8 @@
 from django.db.models.query import Q, QuerySet
+from django.db import backend
+from django.contrib.gis.db.models.fields import GeometryField
 from django.contrib.gis.db.models.postgis import parse_lookup
+from django.db.models.fields import FieldDoesNotExist
 import operator
 
 class GeoQ(Q):
@@ -33,3 +36,11 @@ class GeoQuerySet(QuerySet):
         if len(args) > 0:
             clone._filters = clone._filters & reduce(operator.and_, map(mapper, args))
         return clone
+
+    def kml(self, field_name):
+        field = self.model._meta.get_field(field_name)
+
+        field_col = "%s.%s" % (backend.quote_name(self.model._meta.db_table),
+                            backend.quote_name(field.column))
+        
+        return self.extra(select={'kml':'AsKML(%s,6)' % field_col})

django/contrib/gis/sitemaps.py

@@ -0,0 +1,62 @@
+from django.core import urlresolvers
+from django.contrib.sitemaps import Sitemap
+from django.contrib.gis.db.models.fields import GeometryField
+from django.db.models import get_model, get_models
+from django.template.loader import get_template
+from django.template import Context
+from django.http import HttpResponse
+
+kml_files = [('gis.school', 'location'),
+             ('gis.district', 'boundary')]
+
+
+class KMLSitemap(Sitemap):
+    """
+    A minimal hook to 
+    """
+    def __init__(self, locations=None):
+        if locations is None:
+            self.locations = _build_kml_sources()
+        else:
+            self.locations = locations
+
+    def items(self):
+        return self.locations
+
+    def location(self, obj):
+        return urlresolvers.reverse('django.contrib.gis.sitemaps.kml',
+                                    kwargs={'label':obj[0],
+                                            'field_name':obj[1]})
+
+
+def _build_kml_sources():
+    "Make a mapping of all available KML sources."
+    ret = []
+    for klass in get_models():
+        for field in klass._meta.fields:
+            if isinstance(field, GeometryField):
+                label = "%s.%s" % (klass._meta.app_label,
+                                   klass._meta.module_name)
+                
+                ret.append((label, field.name))
+    return ret
+
+
+class KMLNotFound(Exception):
+    pass
+
+
+def kml(request, label, field_name):
+    placemarks = []
+    klass = get_model(*label.split('.'))
+    if not klass:
+        raise KMLNotFound("You must supply a valid app.model label.  Got %s" % label)
+    #FIXME: GMaps apparently has a limit on size of displayed kml files
+    #  check if paginating w/ external refs (i.e. linked list) helps.
+    placemarks.extend(list(klass._default_manager.kml(field_name)[:100]))
+    #FIXME: other KML features?
+    t = get_template('gis/kml.xml')
+    c = Context({'places':placemarks})
+    
+    return HttpResponse(t.render(c), mimetype='application/vnd.google-earth.kml+xml')
+    

django/contrib/gis/templates/gis/kml.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+ <kml xmlns="http://earth.google.com/kml/2.1">
+   {% for place in places %}
+  <Placemark>
+    <name>{{ place.name|escape }}</name>
+    <description>{{ place.description|escape }}</description>
+     {{ place.kml }}
+  </Placemark>
+   {% endfor %}
+</kml>        

django/contrib/sitemaps/__init__.py

@@ -88,3 +88,24 @@ class GenericSitemap(Sitemap):
         if self.date_field is not None:
             return getattr(item, self.date_field)
         return None
+
+
+class KMLSitemap(Sitemap):
+    """
+    A minimal hook to 
+    """
+    def __init__(self, locations=None):
+        if locations is None:
+            self.locations = []
+        else:
+            self.locations = locations
+
+    def items(self):
+        return self.locations
+
+    def location(self, obj):
+        urlresolvers.reverse('django.contrib.gis.sitemaps.kml',
+                             kwargs={'label':obj[0],
+                                     'field':obj[1]})
+        
+