from django.contrib.admin import ModelAdmin from django.contrib.gis.admin.widgets import OpenLayersWidget from django.contrib.gis.db import models from django.contrib.gis.gdal import OGRGeomType from django.forms import Media spherical_mercator_srid = 3857 class GeoModelAdmin(ModelAdmin): """ The administration options class for Geographic models. Map settings may be overloaded from their defaults to create custom maps. """ # The default map settings that may be overloaded -- still subject # to API changes. default_lon = 0 default_lat = 0 default_zoom = 4 display_wkt = False display_srid = False extra_js = [] num_zoom = 18 max_zoom = False min_zoom = False units = False max_resolution = False max_extent = False modifiable = True mouse_position = True scale_text = True layerswitcher = True scrollable = True map_width = 600 map_height = 400 map_srid = 4326 map_template = 'gis/admin/openlayers.html' openlayers_url = 'https://cdnjs.cloudflare.com/ajax/libs/openlayers/2.13.1/OpenLayers.js' point_zoom = num_zoom - 6 wms_url = 'http://vmap0.tiles.osgeo.org/wms/vmap0' wms_layer = 'basic' wms_name = 'OpenLayers WMS' wms_options = {'format': 'image/jpeg'} debug = False widget = OpenLayersWidget @property def media(self): "Injects OpenLayers JavaScript into the admin." return super().media + Media(js=[self.openlayers_url] + self.extra_js) def formfield_for_dbfield(self, db_field, request, **kwargs): """ Overloaded from ModelAdmin so that an OpenLayersWidget is used for viewing/editing 2D GeometryFields (OpenLayers 2 does not support 3D editing). """ if isinstance(db_field, models.GeometryField) and db_field.dim < 3: # Setting the widget with the newly defined widget. kwargs['widget'] = self.get_map_widget(db_field) return db_field.formfield(**kwargs) else: return super().formfield_for_dbfield(db_field, request, **kwargs) def get_map_widget(self, db_field): """ Return a subclass of the OpenLayersWidget (or whatever was specified in the `widget` attribute) using the settings from the attributes set in this class. """ is_collection = db_field.geom_type in ('MULTIPOINT', 'MULTILINESTRING', 'MULTIPOLYGON', 'GEOMETRYCOLLECTION') if is_collection: if db_field.geom_type == 'GEOMETRYCOLLECTION': collection_type = 'Any' else: collection_type = OGRGeomType(db_field.geom_type.replace('MULTI', '')) else: collection_type = 'None' class OLMap(self.widget): template_name = self.map_template geom_type = db_field.geom_type wms_options = '' if self.wms_options: wms_options = ["%s: '%s'" % pair for pair in self.wms_options.items()] wms_options = ', %s' % ', '.join(wms_options) params = { 'default_lon': self.default_lon, 'default_lat': self.default_lat, 'default_zoom': self.default_zoom, 'display_wkt': self.debug or self.display_wkt, 'geom_type': OGRGeomType(db_field.geom_type), 'field_name': db_field.name, 'is_collection': is_collection, 'scrollable': self.scrollable, 'layerswitcher': self.layerswitcher, 'collection_type': collection_type, 'is_generic': db_field.geom_type == 'GEOMETRY', 'is_linestring': db_field.geom_type in ('LINESTRING', 'MULTILINESTRING'), 'is_polygon': db_field.geom_type in ('POLYGON', 'MULTIPOLYGON'), 'is_point': db_field.geom_type in ('POINT', 'MULTIPOINT'), 'num_zoom': self.num_zoom, 'max_zoom': self.max_zoom, 'min_zoom': self.min_zoom, 'units': self.units, # likely should get from object 'max_resolution': self.max_resolution, 'max_extent': self.max_extent, 'modifiable': self.modifiable, 'mouse_position': self.mouse_position, 'scale_text': self.scale_text, 'map_width': self.map_width, 'map_height': self.map_height, 'point_zoom': self.point_zoom, 'srid': self.map_srid, 'display_srid': self.display_srid, 'wms_url': self.wms_url, 'wms_layer': self.wms_layer, 'wms_name': self.wms_name, 'wms_options': wms_options, 'debug': self.debug, } return OLMap class OSMGeoAdmin(GeoModelAdmin): map_template = 'gis/admin/osm.html' num_zoom = 20 map_srid = spherical_mercator_srid max_extent = '-20037508,-20037508,20037508,20037508' max_resolution = '156543.0339' point_zoom = num_zoom - 6 units = 'm'