Merge pull request #130 from ragsagar/custom_encoder

Attribute for setting JSON Encoder class in JSONResponseMixin

braces/views/_ajax.py

@@ -19,6 +19,7 @@ class JSONResponseMixin(object):
     """
     content_type = None
     json_dumps_kwargs = None
+    json_encoder_class = DjangoJSONEncoder
 
     def get_content_type(self):
         if (self.content_type is not None and
@@ -43,7 +44,7 @@ def render_json_response(self, context_dict, status=200):
         """
         json_context = json.dumps(
             context_dict,
-            cls=DjangoJSONEncoder,
+            cls=self.json_encoder_class,
             **self.get_json_dumps_kwargs()).encode(u'utf-8')
         return HttpResponse(json_context,
                             content_type=self.get_content_type(),
@@ -118,7 +119,7 @@ def render_bad_request_response(self, error_dict=None):
             error_dict = self.error_response_dict
         json_context = json.dumps(
             error_dict,
-            cls=DjangoJSONEncoder,
+            cls=self.json_encoder_class,
             **self.get_json_dumps_kwargs()
         ).encode(u'utf-8')
         return HttpResponseBadRequest(

docs/other.rst

@@ -225,6 +225,36 @@ overriding the `get_content_type()` method.
             # Shown just for illustrative purposes
             return u"application/javascript"
 
+The `JSONResponseMixin` provides another class-level variable 
+`json_encoder_class` to use a custom json encoder with `json.dumps`.
+By default it is `django.core.serializers.json.DjangoJsonEncoder`
+
+::
+
+    from django.core.serializers.json import DjangoJSONEncoder
+
+    from braces.views import JSONResponseMixin
+
+
+    class SetJSONEncoder(DjangoJSONEncoder):
+        """
+        A custom JSONEncoder extending `DjangoJSONEncoder` to handle serialization
+        of `set`.
+        """
+        def default(self, obj):
+            if isinstance(obj, set):
+                return list(obj)
+            return super(DjangoJSONEncoder, self).default(obj)
+
+
+    class GetSetDataView(JSONResponseMixin, View):
+        json_encoder_class = SetJSONEncoder
+
+        def get(self, request, *args, **kwargs):
+            numbers_set = set(range(10))
+            data = {'numbers': numbers_set}
+            return self.render_json_response(data)
+
 .. _JsonRequestResponseMixin:
 
 JsonRequestResponseMixin

tests/helpers.py

@@ -1,5 +1,6 @@
 from django import test
 from django.contrib.auth.models import AnonymousUser
+from django.core.serializers.json import DjangoJSONEncoder
 
 
 class TestViewHelper(object):
@@ -47,3 +48,16 @@ def dispatch_view(self, request, args=None, kwargs=None, view_class=None,
         """
         view = self.build_view(request, args, kwargs, view_class, **viewkwargs)
         return view.dispatch(request, *view.args, **view.kwargs)
+
+
+class SetJSONEncoder(DjangoJSONEncoder):
+    """
+    A custom JSONEncoder extending `DjangoJSONEncoder` to handle serialization
+    of `set`.
+    """
+    def default(self, obj):
+        if isinstance(obj, set):
+            return list(obj)
+        return super(DjangoJSONEncoder, self).default(obj)
+
+

tests/test_ajax_mixins.py

@@ -11,7 +11,8 @@
 from .compat import force_text
 from .factories import ArticleFactory, UserFactory
 from .helpers import TestViewHelper
-from .views import SimpleJsonView, JsonRequestResponseView
+from .views import (SimpleJsonView, JsonRequestResponseView,
+                    CustomJsonEncoderView)
 from .compat import json
 
 
@@ -136,6 +137,13 @@ def test_pretty_json(self):
         self.assertEqual(normal_json, pretty_json)
         self.assertTrue(len(pretty_content) > len(normal_content))
 
+    def test_json_encoder_class_atrribute(self):
+        """
+        Tests setting custom `json_encoder_class` attribute.
+        """
+        data = json.loads(self.get_content(u'/simple_json_custom_encoder/'))
+        self.assertEqual({u'numbers': [1, 2, 3]}, data)
+
 
 class TestJsonRequestResponseMixin(TestViewHelper, test.TestCase):
     view_class = JsonRequestResponseView

tests/urls.py

@@ -80,6 +80,7 @@
 
     # JSONResponseMixin tests
     url(r'^simple_json/$', views.SimpleJsonView.as_view()),
+    url(r'^simple_json_custom_encoder/$', views.CustomJsonEncoderView.as_view()),
     url(r'^simple_json_400/$', views.SimpleJsonBadRequestView.as_view()),
     url(r'^article_list_json/$', views.ArticleListJsonView.as_view()),
 

tests/views.py

@@ -12,6 +12,7 @@
 
 from .models import Article, CanonicalArticle
 from .forms import ArticleForm, FormWithUserKwarg
+from .helpers import SetJSONEncoder
 
 
 class OkView(View):
@@ -79,6 +80,18 @@ def get(self, request):
         return self.render_json_response(object)
 
 
+class CustomJsonEncoderView(views.JSONResponseMixin, View):
+    """
+    A view for testing JSONResponseMixin's `json_encoder_class` attribute
+    with custom JSONEncoder class.
+    """
+    json_encoder_class = SetJSONEncoder
+
+    def get(self, request):
+        object = {'numbers': set([1, 2, 3])}
+        return self.render_json_response(object)
+
+
 class SimpleJsonBadRequestView(views.JSONResponseMixin, View):
     """
     A view for testing JSONResponseMixin's render_json_response() method with