Merge pull request #94 from era/master

Refresh token support

docs/source/adapter.rst

@@ -0,0 +1,19 @@
+==========
+Adapter
+==========
+
+Authentication helpers
+---------------------
+
+You can implement the ```refresh_authentication``` and ```is_authentication_expired``` methods in your Tapioca Client to refresh your authentication token every time that it expires.
+```is_authentication_expired``` receives an error object from the request method (it contains the server response and HTTP Status code). You can use it to decide if a request failed because of the token. This method should return true if the authentication is expired or false otherwise.
+
+If the authentication is expired, ```refresh_authentication``` is called. This method does not receive any parameter.
+
+.. code-block:: python
+    def is_authentication_expired(self,error)
+        ....
+    def refresh_authentication(self):
+        ...
+
+

tapioca/adapters.py

@@ -81,6 +81,11 @@ def get_iterator_next_request_kwargs(self, iterator_request_kwargs,
                                          response_data, response):
         raise NotImplementedError()
 
+    def is_authentication_expired(self, error):
+        raise NotImplementedError()
+
+    def refresh_authentication(self):
+        raise NotImplementedError()
 
 class FormAdapterMixin(object):
 
@@ -90,13 +95,14 @@ def format_data_to_request(self, data):
     def response_to_native(self, response):
         return {'text': response.text}
 
-
 class JSONAdapterMixin(object):
 
     def get_request_kwargs(self, api_params, *args, **kwargs):
         arguments = super(JSONAdapterMixin, self).get_request_kwargs(
             api_params, *args, **kwargs)
-
+        if 'refresh_auth' in arguments:
+            del arguments['refresh_auth']
+
         if 'headers' not in arguments:
             arguments['headers'] = {}
         arguments['headers']['Content-Type'] = 'application/json'

tapioca/tapioca.py

@@ -192,8 +192,13 @@ def _make_request(self, request_method, *args, **kwargs):
             data = self._api.process_response(response)
         except ResponseProcessException as e:
             client = self._wrap_in_tapioca(e.data, response=response,
-                                           request_kwargs=request_kwargs)
-            raise e.tapioca_exception(client=client)
+                                            request_kwargs=request_kwargs)
+            tapioca_exception = e.tapioca_exception(client=client)
+            if 'refresh_auth' in kwargs and kwargs['refresh_auth'] and self._api.is_authentication_expired(tapioca_exception):
+                self._api.refresh_authentication()
+                return self._make_request(request_method, args, kwargs)
+            else:
+                raise tapioca_exception
 
         return self._wrap_in_tapioca(data, response=response,
                                      request_kwargs=request_kwargs)

tests/client.py

@@ -4,7 +4,7 @@
 
 from tapioca.adapters import (
     TapiocaAdapter, JSONAdapterMixin,
-    generate_wrapper_from_adapter)
+    generate_wrapper_from_adapter) 
 from tapioca.serializers import SimpleSerializer
 
 
@@ -27,6 +27,7 @@
 
 
 class TesterClientAdapter(JSONAdapterMixin, TapiocaAdapter):
+
     serializer_class = None
     api_root = 'https://api.test.com'
     resource_mapping = RESOURCE_MAPPING
@@ -44,6 +45,11 @@ def get_iterator_next_request_kwargs(self, iterator_request_kwargs,
         if url:
             return {'url': url}
 
+    def is_authentication_expired(self, error):
+        return error.status_code == 401
+
+    def refresh_authentication(self):
+        pass
 
 TesterClient = generate_wrapper_from_adapter(TesterClientAdapter)
 

tests/test_tapioca.py

@@ -10,6 +10,7 @@
 
 from tapioca.tapioca import TapiocaClient
 from tapioca.serializers import SimpleSerializer
+from tapioca.exceptions import ClientError
 
 from tests.client import TesterClient, SerializerClient
 
@@ -219,6 +220,34 @@ def test_post_request(self):
 
         self.assertEqual(response().data, {'data': {'key': 'value'}})
 
+    @responses.activate
+    def test_token_expired_and_not_refresh_flag(self):
+        responses.add(responses.POST, self.wrapper.test().data,
+                      body='{"error": "Token expired"}',
+                      status=401,
+                      content_type='application/json')
+        with self.assertRaises(ClientError) as context:
+            response = self.wrapper.test().post()
+
+    @responses.activate
+    def test_token_expired_and_refresh_flag(self):
+        self.first_call = True
+        responses.add_callback(
+          responses.POST, self.wrapper.test().data,
+          callback=self.request_callback,
+          content_type='application/json',
+        )
+
+        response = self.wrapper.test().post(refresh_auth=True)
+
+    def request_callback(self, request):
+      if self.first_call:
+        self.first_call = False
+        return (401, {'content_type':'application/json'}, json.dumps('{"error": "Token expired"}'))
+      else:
+        self.first_call = None
+        return (201, {'content_type':'application/json'}, json.dumps('{"error": "Token expired"}'))
+
     @responses.activate
     def test_put_request(self):
         responses.add(responses.PUT, self.wrapper.test().data,