JSONP renderer and tests

djangorestframework/renderers.py

@@ -26,6 +26,7 @@ __all__ = (
     'BaseRenderer',
     'TemplateRenderer',
     'JSONRenderer',
+    'JSONPRenderer',
     'DocumentingHTMLRenderer',
     'DocumentingXHTMLRenderer',
     'DocumentingPlainTextRenderer',
@@ -113,6 +114,46 @@ class JSONRenderer(BaseRenderer):
         return json.dumps(obj, cls=DateTimeAwareJSONEncoder, indent=indent, sort_keys=sort_keys)
 
 
+class JSONPRenderer(BaseRenderer):
+    """
+    Renderer which serializes to JSONP
+    """
+    media_type = 'application/json-p'
+    format = 'json-p'
+    
+    callback_parameter = 'callback'
+
+    def render(self, obj=None, media_type=None):
+        """
+        Renders *obj* into serialized JSONP.
+        
+        The callback function name is taken from the 'callback' parameter
+        contained in the jsonp request.
+        """
+        callback = self.view.request.GET.get(self.callback_parameter, self.callback_parameter)
+            
+        if obj is None:
+            serialized_obj = ''
+        else:
+            json_renderer = self._get_renderer(JSONRenderer.media_type)
+            if json_renderer is None:
+                serialized_obj = json.dumps(obj, cls=DateTimeAwareJSONEncoder)
+            else:
+                serialized_obj = json_renderer.render(obj, JSONRenderer.media_type)
+
+        return "%s(%s);" % (callback, serialized_obj)
+       
+    def _get_renderer(self, media_type=None):
+        """
+        Get first view renderer that serializes *media_type*.
+        """
+        for r in self.view.renderers:
+            renderer = r(self.view)
+            if renderer.can_handle_response(media_type):
+                return renderer
+        return None
+
+
 class XMLRenderer(BaseRenderer):
     """
     Renderer which serializes to XML.
@@ -376,6 +417,7 @@ class DocumentingPlainTextRenderer(DocumentingTemplateRenderer):
 
 
 DEFAULT_RENDERERS = ( JSONRenderer,
+                      JSONPRenderer,
                       DocumentingHTMLRenderer,
                       DocumentingXHTMLRenderer,
                       DocumentingPlainTextRenderer,

djangorestframework/tests/renderers.py

@@ -3,8 +3,10 @@ from django import http
 from django.test import TestCase
 
 from djangorestframework import status
+from djangorestframework.views import View
 from djangorestframework.compat import View as DjangoView
-from djangorestframework.renderers import BaseRenderer, JSONRenderer, YAMLRenderer
+from djangorestframework.renderers import BaseRenderer, JSONRenderer, YAMLRenderer, \
+    JSONPRenderer
 from djangorestframework.parsers import JSONParser, YAMLParser
 from djangorestframework.mixins import ResponseMixin
 from djangorestframework.response import Response
@@ -39,10 +41,16 @@ class MockView(ResponseMixin, DjangoView):
         response = Response(DUMMYSTATUS, DUMMYCONTENT)
         return self.render(response)
     
+class MockGETView(View):
+    def get(self, request, **kwargs):
+        return {'foo':['bar','baz']}
+    
 
 urlpatterns = patterns('',
     url(r'^.*\.(?P<format>.+)$', MockView.as_view(renderers=[RendererA, RendererB])),
     url(r'^$', MockView.as_view(renderers=[RendererA, RendererB])),
+    url(r'^jsonp/jsonrenderer$', MockGETView.as_view(renderers=[JSONRenderer, JSONPRenderer])),
+    url(r'^jsonp/nojsonrenderer$', MockGETView.as_view(renderers=[JSONPRenderer])),
 )
 
 
@@ -188,8 +196,46 @@ class JSONRendererTests(TestCase):
 
         content = renderer.render(obj, 'application/json')
         (data, files) = parser.parse(StringIO(content))
-        self.assertEquals(obj, data)    
+        self.assertEquals(obj, data)
+        
 
+class JSONPRendererTests(TestCase):
+    """
+    Tests specific to the JSONP Renderer
+    """
+
+    urls = 'djangorestframework.tests.renderers'
+
+    def test_without_callback_with_json_renderer(self):
+        """
+        Test JSONP rendering with View JSON Renderer.
+        """
+        resp = self.client.get('/jsonp/jsonrenderer',
+                               HTTP_ACCEPT='application/json-p')
+        self.assertEquals(resp.status_code, 200)
+        self.assertEquals(resp['Content-Type'], 'application/json-p')
+        self.assertEquals(resp.content, 'callback(%s);' % _flat_repr)
+        
+    def test_without_callback_without_json_renderer(self):
+        """
+        Test JSONP rendering without View JSON Renderer.
+        """
+        resp = self.client.get('/jsonp/nojsonrenderer',
+                               HTTP_ACCEPT='application/json-p')
+        self.assertEquals(resp.status_code, 200)
+        self.assertEquals(resp['Content-Type'], 'application/json-p')
+        self.assertEquals(resp.content, 'callback(%s);' % _flat_repr)
+        
+    def test_with_callback(self):
+        """
+        Test JSONP rendering with callback function name.
+        """
+        callback_func = 'myjsonpcallback'
+        resp = self.client.get('/jsonp/nojsonrenderer?callback='+callback_func,
+                               HTTP_ACCEPT='application/json-p')
+        self.assertEquals(resp.status_code, 200)
+        self.assertEquals(resp['Content-Type'], 'application/json-p')
+        self.assertEquals(resp.content, '%s(%s);' % (callback_func, _flat_repr))
 
 
 if YAMLRenderer: