Allow custom resource constructor args

Author: multimeric

flask_rest_jsonapi/api.py

@@ -69,7 +69,11 @@ def route(self, resource, view, *urls, **kwargs):
         resource.view = view
         url_rule_options = kwargs.get('url_rule_options') or dict()
 
-        view_func = resource.as_view(view)
+        # Allow the customization of the resource class instance
+        resource_args = kwargs.get('resource_args', [])
+        resource_kwargs = kwargs.get('resource_kwargs', {})
+
+        view_func = resource.as_view(view, *resource_args, **resource_kwargs)
 
         if 'blueprint' in kwargs:
             resource.view = '.'.join([kwargs['blueprint'].name, resource.view])

flask_rest_jsonapi/resource.py

@@ -52,7 +52,7 @@ def __new__(cls, name, bases, d):
 class Resource(MethodView):
     """Base resource class"""
 
-    def __new__(cls):
+    def __new__(cls, *args, **kwargs):
         """Constructor of a resource instance"""
         if hasattr(cls, '_data_layer'):
             cls._data_layer.resource = cls

tests/test_sqlalchemy_data_layer.py

@@ -19,6 +19,7 @@
 from flask_rest_jsonapi.data_layers.alchemy import SqlalchemyDataLayer
 from flask_rest_jsonapi.data_layers.base import BaseDataLayer
 from flask_rest_jsonapi.data_layers.filtering.alchemy import Node
+from flask_rest_jsonapi.decorators import check_headers, check_method_requirements, jsonapi_exception_formatter
 import flask_rest_jsonapi.decorators
 import flask_rest_jsonapi.resource
 import flask_rest_jsonapi.schema
@@ -983,6 +984,46 @@ def test_get_list_response(client, register_routes):
         assert response.status_code == 200
 
 
+class TestResourceArgs:
+    def test_resource_args(self, app):
+        class TestResource(ResourceDetail):
+            """
+            This fake resource always renders a constructor parameter
+            """
+            def __init__(self, *args, **kwargs):
+                super().__init__()
+                self.constant = args[0]
+
+            def get(self):
+                return self.constant
+        api = Api(app=app)
+        api.route(TestResource, 'resource_args', '/resource_args', resource_args=['hello!'])
+        api.init_app()
+        with app.test_client() as client:
+            rv = client.get('/resource_args')
+            assert rv.json == 'hello!'
+
+    def test_resource_kwargs(self, app):
+        class TestResource(ResourceDetail):
+            """
+            This fake resource always renders a constructor parameter
+            """
+            def __init__(self, *args, **kwargs):
+                super().__init__()
+                self.constant = kwargs.get('constant')
+
+            def get(self):
+                return self.constant
+        api = Api(app=app)
+        api.route(TestResource, 'resource_kwargs', '/resource_kwargs', resource_kwargs={
+            'constant': 'hello!'
+        })
+        api.init_app()
+        with app.test_client() as client:
+            rv = client.get('/resource_kwargs')
+            assert rv.json == 'hello!'
+
+
 # test various Accept headers
 def test_single_accept_header(client, register_routes):
     with client: