gundotio#56: Implement a view without model

- Created a workaround to user a fake model
- updated documentation explaining how to use it

README.md

@@ -31,6 +31,7 @@ Table of contents
   - [UpdateAPI](#updateapi)
   - [ActionAPI](#actionapi)
   - [DeleteAPI](#deleteapi)
+  - [WithoutModel](#withoutmodel)
 - [Browsable API](#browsable-api)
 - [Bundle loading](#bundle-loading)
 - [Debugging](#debugging)
@@ -361,6 +362,35 @@ class BookDetailAPI(DeleteAPI, DetailAPI):
 Deletes return a 204 no content response, no serializer is required.
 
 
+### WithoutModel
+
+If you want to build an API without any model, you just need to extend the `WithoutModel` class
+and then one of the classes above - like [ListAPI](#listapi) - or overwrite one of the handles - 
+like `get` or `post`.
+
+```python
+
+class CustomInfoAPI(WithoutModel, ListAPI):
+
+    def get(self, request, *args, **kwargs):
+      return self.render_to_response(data={"field": value})
+
+```
+
+You can also overwrite the `get_queryset` method and define the `Serializer` class
+
+```python
+
+class CustomInfoAPI(WithoutModel, ListAPI):
+
+    serializer = MyCustomSerializer
+
+    def get_queryset(self):
+       return MyModel.objects.filter(...)
+
+```
+
+
 Browsable API
 -------------
 

tests/test_views.py

@@ -511,21 +511,75 @@ def test_user_update(client, db, method, user):
     assert result["email"] == "[email protected]"
 
 
-def test_when_using_a_detail_view_without_model_must_return_expected_result(client):
-    response = client.get("/without-model/detail")
+def test_when_getting_details_of_a_view_without_model_must_return_empty_result(
+        client, db):
+
+    response = client.get(f"/without-model/{uuid4()}")
+    assert response
+    assert response.status_code == 200, response
+    assert response.json() == {}
+
+
+@parametrize("method", ["PATCH", "PUT"])
+def test_when_changing_details_of_a_view_without_model_must_return_expected_result(client, db, method):
+    payload = dict(field="value")
+    response = client.generic(method, f"/without-model/{uuid4()}", payload)
+    result = response.json()
+    assert response.status_code == 200, result
+    assert result == {}
+
+
+def test_when_deleting_details_of_a_view_without_model_must_return_expected_result(client, db, task):
+    response = client.delete(f"/without-model/{task.custom_id}")
+    assert response.status_code == 204, response.content
+    assert response.content == b""
+
+
+def test_when_posting_to_a_view_without_model_must_return_empty_response(client, db):
+
+    response = client.post("/without-model/", dict(name="Task Name"))
+    assert response.status_code == 201
+    assert response.json() == {}
+
+
+def test_when_using_a_list_view_without_model_but_with_queryset_must_return_expected_result(
+        client, db, task):
+
+    task_id = task.custom_id
+    task_name = task.name
+
+    response = client.get("/without-model/")
     assert response
     assert response.status_code == 200, response
-    assert response.json() == {"field_name": "field_value"}
+    assert response.json() == {
+        'pagination': {
+            'count': 0,
+            'page': 1,
+            'pages': 1
+        },
+        'data': []
+    }
 
 
 def test_when_using_a_list_view_without_model_must_return_expected_result(client):
-    with pytest.raises(AttributeError):
-        response = client.get("/without-model/")
+    response = client.get("/without-model-overriding-handler/")
+    assert response
+    assert response.status_code == 200, response
+    assert response.json() == {"data": [{"field_name": "field_value"}]}
+
 
+def test_when_using_a_list_view_without_model_with_custom_queryset_must_return_expected_result(
+    client, db, task):
 
-def test_when_using_a_list_view_without_model_but_with_queryset_must_return_expected_result(client):
-    with pytest.raises(AttributeError):
-        response = client.get("/without-model-queryset/")
+    task_id = task.custom_id
+    task_name = task.name
 
+    response = client.get("/custom-tasks/")
+    assert response
+    assert response.status_code == 200, response
+    assert response.json() == {
+        "pagination": {"count": 1, "page": 1, "pages": 1 },
+        "data": [{"id": str(task_id), "name": task_name}]
+    }
 
 

tests/urls.py

@@ -10,7 +10,8 @@
     path("user/", views.UserSelf.as_view()),
     path("users/", views.UserList.as_view()),
     path("users/<int:id>/", views.UserDetail.as_view()),
+    path("without-model-overriding-handler/", views.ViewWithoutModelListOverridingHandler.as_view()),
+    path("without-model/<uuid:task_id>", views.ViewWithoutModelDetail.as_view()),
     path("without-model/", views.ViewWithoutModelList.as_view()),
-    path("without-model/detail", views.ViewWithoutModelDetail.as_view()),
-    path("without-model-queryset/", views.ViewWithoutModelListWithQuerySet.as_view()),
+    path("custom-tasks/", views.CustomTaskAPI.as_view()),
 ]

tests/views.py

@@ -3,11 +3,11 @@
 from django.db.models import F, Prefetch, Value, Model
 from django.db.models.functions import Concat
 
-from tests.models import Profile
-from tests.serializers import ProfileSerializer, UserSerializer, DetachedModelSerializer
+from tests.models import Profile, Task
+from tests.serializers import ProfileSerializer, UserSerializer, DetachedModelSerializer, TaskSerializer
 from worf.exceptions import AuthenticationError
 from worf.permissions import Authenticated, PublicEndpoint, Staff
-from worf.views import ActionAPI, CreateAPI, DeleteAPI, DetailAPI, ListAPI, UpdateAPI
+from worf.views import ActionAPI, CreateAPI, DeleteAPI, DetailAPI, ListAPI, UpdateAPI, WithoutModel
 
 
 class ProfileList(CreateAPI, ListAPI):
@@ -112,18 +112,22 @@ def get_instance(self):
         return self.request.user
 
 
-class ViewWithoutModelDetail(DetailAPI):
-    model = None
+class ViewWithoutModelDetail(WithoutModel, DeleteAPI, UpdateAPI, DetailAPI):
+    pass
 
-    def get(self, *args, **kwargs):
-        return self.render_to_response(data={"field_name": "field_value"})
+
+class ViewWithoutModelList(WithoutModel, CreateAPI, ListAPI):
+    pass
 
 
-class ViewWithoutModelList(ListAPI):
+class ViewWithoutModelListOverridingHandler(WithoutModel, ListAPI):
 
     def get(self, *args, **kwargs):
         return self.render_to_response(data={"data": [{"field_name": "field_value"}]})
 
 
-class ViewWithoutModelListWithQuerySet(ListAPI):
-    pass
+class CustomTaskAPI(WithoutModel, ListAPI):
+    serializer = TaskSerializer
+
+    def get_queryset(self):
+        return Task.objects.all()

worf/assigns.py

@@ -4,11 +4,14 @@
 
 
 class AssignAttributes:
+
+    def get_model_attr(self, key):
+        return getattr(self.model, key)
+
     def save(self, instance, bundle):
         items = [
-            (key, getattr(self.model, key), value) for key, value in bundle.items()
+            (key, self.get_model_attr(key), value) for key, value in bundle.items()
         ]
-
         for key, attr, value in items:
             if isinstance(value, models.Model):
                 setattr(instance, key, value)

worf/views/__init__.py

@@ -1,5 +1,5 @@
 from worf.views.action import ActionAPI  # noqa: F401
-from worf.views.base import AbstractBaseAPI, APIResponse  # noqa: F401
+from worf.views.base import AbstractBaseAPI, APIResponse, WithoutModel, NoModel  # noqa: F401
 from worf.views.create import CreateAPI  # noqa: F401
 from worf.views.delete import DeleteAPI  # noqa: F401
 from worf.views.detail import DetailAPI, DetailUpdateAPI  # noqa: F401

worf/views/base.py

@@ -13,6 +13,7 @@
 from django.utils.decorators import method_decorator
 from django.views import View
 from django.views.decorators.cache import never_cache
+from django.db import models
 
 from worf.casing import camel_to_snake, snake_to_camel
 from worf.conf import settings
@@ -25,10 +26,41 @@
     WorfError,
 )
 from worf.renderers import render_response
-from worf.serializers import SerializeModels
+from worf.serializers import SerializeModels, Serializer
 from worf.validators import ValidateFields
 
 
+class NoModel(models.Model):
+    """A dummy model to pass through all the code that is deeply coupled with DJango models
+    TODO remove inheritance with django model to avoid any side effect
+    """
+
+    def refresh_from_db(self):
+        warnings.warn("Trying to 'refresh' a detached model")
+
+    def delete(self):
+        warnings.warn("Trying to 'delete' a detached model")
+
+
+class WithoutModel:
+
+    model = NoModel
+    payload_key = "data"
+    serializer = Serializer
+
+    def validate(self):
+        warnings.warn("APIs without models have no validation")
+
+    def save(self, instance, bundle):
+        warnings.warn("When using an API without model you MUST implement save method")
+
+    def get_queryset(self):
+        return NoModel.objects.none()
+
+    def get_instance(self):
+        return NoModel()
+
+
 @method_decorator(never_cache, name="dispatch")
 class APIResponse(View):
     def __init__(self, *args, **kwargs):