Merge pull request mozboz#9 from webisteme/master

New API endpoint

Author: mozboz

README.md

@@ -18,18 +18,30 @@ several operations for querying data inside JSONB fields.
 
 See: https://docs.djangoproject.com/en/1.10/ref/contrib/postgres/fields/#containment-and-key-operations
 
-## Usage
-
-    python manage.py transformap -i jobs/jobfile.json
-
-Admin interface: /admin
-API URL: /places-api/
-New jobs should be created as .YAML files in jobs/
-
 ## Misc
 
 ETL business logic: places/management/commands
 REST API configuration: places/api.py
 
+## Deployment
+
+For development, testing or demo purposes, use the Django development server:
+
+python manage.py runserver 0.0.0.0:9000
+
+Navigate to http://localhost:9000 ...
+
+- /admin for the Admin area
+- /places-api for the REST API interface
+- /map-instance/MAP-INSTANCE-ID for the GEOJSON API
+
+For production use, deploy Django using WSGI. See:
+https://docs.djangoproject.com/en/1.10/howto/deployment/wsgi/
+
+## Usage
+
+To run a job, create a YAML job file in /jobs, then:
 
+    python manage.py transformap -i jobs/jobfile.yaml
 
+This fetch and save the partner's data to the database.

places/api.py

@@ -15,17 +15,34 @@ class MapOwnerViewSet(viewsets.ModelViewSet):
     queryset = MapOwner.objects.all()
     serializer_class = MapOwnerSerializer
 
-# Map Instance
 
-class MapInstanceSerializer(serializers.HyperlinkedModelSerializer):
+
+# Map Data
+
+class MapDataSerializer(serializers.HyperlinkedModelSerializer):
+    class Meta:
+        model = MapData
+        fields = ('map_instance', 'map_object', 'schema_field', 'field_value', 'date_created', 'date_modified')
+
+class MapDataViewSet(viewsets.ModelViewSet):
+    queryset = MapData.objects.all()
+    serializer_class = MapDataSerializer
+    
+
+
+# Map Instance (lite)
+
+class MapInstanceSerializer(serializers.ModelSerializer):
+
     class Meta:
         model = MapInstance
-        fields = ('schema', 'map_definition', 'date_created', 'date_modified')
+        fields = ('id', 'schema', 'map_definition', 'date_created', 'date_modified',)
 
 class MapInstanceViewSet(viewsets.ModelViewSet):
     queryset = MapInstance.objects.all()
     serializer_class = MapInstanceSerializer
-    
+
+
 # Map Object
 
 class MapObjectSerializer(serializers.HyperlinkedModelSerializer):
@@ -36,17 +53,6 @@ class Meta:
 class MapObjectViewSet(viewsets.ModelViewSet):
     queryset = MapObject.objects.all()
     serializer_class = MapObjectSerializer
-    
-# Map Data
-
-class MapDataSerializer(serializers.HyperlinkedModelSerializer):
-    class Meta:
-        model = MapData
-        fields = ('map_instance', 'map_object', 'schema_field', 'field_value', 'date_created', 'date_modified')
-
-class MapDataViewSet(viewsets.ModelViewSet):
-    queryset = MapData.objects.all()
-    serializer_class = MapDataSerializer
 
 # Map Definition
 

places/models.py

@@ -49,7 +49,7 @@ class MapInstance(models.Model):
     date_modified = models.DateTimeField(auto_now=True)
 
     def __unicode__(self):
-        return u'%s' % self.map_definition
+        return u'%s %s' % (self.map_definition, self.id)
 
     class Meta:
         db_table = 'map_instances'

places/views.py

@@ -1,3 +1,80 @@
+from urlparse import urlparse
+
 from django.shortcuts import render
+from django.http import HttpResponse, JsonResponse
+from django.core.exceptions import ObjectDoesNotExist
+
+from places.models import MapInstance, MapData, MapObject
 
 # Create your views here.
+
+def map_instance_geojson(request, map_instance_id):
+
+    '''
+    Fetched all objects (and properties) for a given map instance, 
+    returns a GEOJSON feature collection.
+    '''
+    
+    # Fetch the map instance
+    
+    try:
+        map_instance = MapInstance.objects.get(id=map_instance_id)
+    except ObjectDoesNotExist:
+        return JsonResponse({"Error" : "Map Instance with ID %s does not exist!" % map_instance_id})
+    
+    # Deduce URL from request
+    
+    request_url = urlparse(request.build_absolute_uri())
+    base_url = 'http://%s%s' % (request_url.netloc, request_url.path)
+    
+    # Set pagination params
+    
+    page = int(request.GET.get('page', 1))
+    x = (page - 1) * 25
+    y = page * 25
+    
+    # Prepare GEOJSON response
+    
+    response = {
+        "type"  : "Feature Collection",
+        "count" : 25,
+        "next"  : "%s?page=%s" % (base_url, page + 1),
+    }
+    
+    if page <= 1:
+        response['previous'] = None 
+    else:
+        response['previous'] = "%s?page=%s" % (base_url, page - 1)
+        
+    # Fetch and serialise map objects
+    
+    map_objects = MapObject.objects.filter(map_instance=map_instance).order_by('id')[x:y]
+    
+    features = []
+    for map_object in map_objects:
+        feature = {
+            "type" : "Feature",
+            "geometry" : {
+                "type" : "Point",
+                "coordinates": [
+                    float(map_object.longitude),
+                    float(map_object.latitude),
+                ]
+            },
+            "properties" : {}
+        }
+        
+        object_data = MapData.objects.filter(map_object=map_object)
+        
+        for field in object_data:
+            field_name = field.schema_field
+            feature["properties"][field.schema_field.field_name] = field.field_value
+            
+        features.append(feature)
+        
+    response['features'] = features
+
+    return JsonResponse(response, safe=False)
+    
+    
+    

tfm/urls.py

@@ -1,10 +1,11 @@
 from django.conf.urls import url, include
 from django.contrib import admin
 
-import places.api
+import places.api, places.views
 
 
 urlpatterns = [
     url(r'^admin/', admin.site.urls),
     url(r'^places-api/', include(places.api.router.urls)),
+    url(r'^map-instance/(?P<map_instance_id>\d+)/$', places.views.map_instance_geojson)
 ]