async

utils/api/api.py

@@ -1,7 +1,10 @@
+import asyncio
 import functools
+import inspect
 import json
 import logging
 
+from asgiref.sync import sync_to_async
 from django.http import HttpResponse, QueryDict
 from django.utils.decorators import method_decorator
 from django.views.decorators.csrf import csrf_exempt
@@ -162,6 +165,77 @@ class CSRFExemptAPIView(APIView):
         return super(CSRFExemptAPIView, self).dispatch(request, *args, **kwargs)
 
 
+class AsyncAPIView(APIView):
+    view_is_async = True
+
+    def __init_subclass__(cls, **kwargs):
+        super().__init_subclass__(**kwargs)
+        cls.view_is_async = True
+
+    async def dispatch(self, request, *args, **kwargs):
+        if self.request_parsers:
+            try:
+                request.data = self._get_request_data(self.request)
+            except ValueError as e:
+                return self.error(err="invalid-request", msg=str(e))
+        try:
+            handler = getattr(self, request.method.lower(), self.http_method_not_allowed)
+            response = handler(request, *args, **kwargs)
+            if asyncio.iscoroutine(response):
+                response = await response
+            return response
+        except APIError as e:
+            ret = {"msg": e.msg}
+            if e.err:
+                ret["err"] = e.err
+            return self.error(**ret)
+        except Exception as e:
+            logger.exception(e)
+            return self.server_error()
+
+    def serialize_data(self, object_serializer, data, **kwargs):
+        return object_serializer(data, **kwargs).data
+
+    async def async_serialize_data(self, object_serializer, data, **kwargs):
+        return await sync_to_async(
+            self.serialize_data,
+            thread_sensitive=True,
+        )(object_serializer, data, **kwargs)
+
+    async def async_paginate_data(self, request, query_set, object_serializer=None):
+        try:
+            limit = int(request.GET.get("limit", "10"))
+        except ValueError:
+            limit = 10
+        if limit < 0 or limit > 250:
+            limit = 10
+        try:
+            offset = int(request.GET.get("offset", "0"))
+        except ValueError:
+            offset = 0
+        if offset < 0:
+            offset = 0
+        count, results = await asyncio.gather(
+            query_set.acount(),
+            sync_to_async(lambda: list(query_set[offset:offset + limit]), thread_sensitive=True)(),
+        )
+        if object_serializer:
+            results = await self.async_serialize_data(
+                object_serializer,
+                results,
+                many=True,
+                context={"request": request},
+            )
+        data = {"results": results, "total": count}
+        return data
+
+
+class CSRFExemptAsyncAPIView(AsyncAPIView):
+    @method_decorator(csrf_exempt)
+    async def dispatch(self, request, *args, **kwargs):
+        return await super().dispatch(request, *args, **kwargs)
+
+
 def validate_serializer(serializer):
     """
     @validate_serializer(TestSerializer)
@@ -169,6 +243,20 @@ def validate_serializer(serializer):
         return self.success(request.data)
     """
     def validate(view_method):
+        if inspect.iscoroutinefunction(view_method):
+            @functools.wraps(view_method)
+            async def async_handle(*args, **kwargs):
+                self = args[0]
+                request = args[1]
+                s = serializer(data=request.data)
+                if s.is_valid():
+                    request.data = s.data
+                    request.serializer = s
+                    return await view_method(*args, **kwargs)
+                else:
+                    return self.invalid_serializer(s)
+            return async_handle
+
         @functools.wraps(view_method)
         def handle(*args, **kwargs):
             self = args[0]
@@ -180,7 +268,6 @@ def validate_serializer(serializer):
                 return view_method(*args, **kwargs)
             else:
                 return self.invalid_serializer(s)
-
         return handle
 
     return validate