support .geojson with Accept: application/json

default_settings.py

@@ -50,7 +50,10 @@
 
     'DEFAULT_FILTER_BACKENDS': (
         'wq.db.rest.filters.FilterBackend',
-    )
+    ),
+
+    'DEFAULT_CONTENT_NEGOTIATION_CLASS':
+        'wq.db.rest.negotiation.ContentNegotiation'
 }
 
 # wq.db settings

rest/negotiation.py

@@ -0,0 +1,21 @@
+from rest_framework.negotiation import DefaultContentNegotiation
+
+
+JSON = 'application/json'
+GEOJSON = 'application/geo+json'
+
+
+class ContentNegotiation(DefaultContentNegotiation):
+    """
+    Some clients (such as Mapbox GL) might only Accept: application/json
+    """
+    def filter_renderers(self, renderers, format):
+        self._format = format
+        return super().filter_renderers(renderers, format)
+
+    def get_accept_list(self, request):
+        accepts = super().get_accept_list(request)
+        if getattr(self, '_format', None) == 'geojson':
+            if JSON in accepts and GEOJSON not in accepts:
+                accepts.append(GEOJSON)
+        return accepts