Add Class-Based View Mixins (#340)

docs/usage/index.rst

@@ -11,9 +11,10 @@ JavaScript.
 
 .. toctree::
    :titlesonly:
-   
+
    views
    decorators
+   mixins
    templates
    javascript
    cli

docs/usage/mixins.rst

@@ -0,0 +1,42 @@
+.. _usage-mixins:
+
+============================
+Mixins for Class Based Views
+============================
+
+Waffle provides mixins to add to Class Based Views.
+
+When the flag or switch is active, or a sample returns True, the view executes normally.
+When it is inactive, the view returns a 404.
+
+WaffleFlagMixin
+===============
+
+.. code-block:: python
+
+    from waffle.mixins import WaffleFlagMixin
+
+    class MyClass(WaffleFlagMixin, View):
+        waffle_flag = "my_flag"
+
+
+WaffleSwitchMixin
+=================
+
+.. code-block:: python
+
+    from waffle.mixins import WaffleSwitchMixin
+
+    class MyClass(WaffleSwitchMixin, View):
+        waffle_switch= "my_switch"
+
+
+WaffleSampleMixin
+=================
+
+.. code-block:: python
+
+    from waffle.mixins import WaffleSampleMixin
+
+    class MyClass(WaffleSampleMixin, View):
+        waffle_switch= "my_sample"

test_app/views.py

@@ -1,9 +1,11 @@
 from django.http import HttpResponse
 from django.shortcuts import render
 from django.template.loader import render_to_string
+from django.views.generic import View
 
 from waffle import flag_is_active
 from waffle.decorators import waffle_flag, waffle_switch
+from waffle.mixins import WaffleFlagMixin, WaffleSampleMixin, WaffleSwitchMixin
 
 
 def flag_in_view(request):
@@ -105,3 +107,32 @@ def flagged_view_with_args_with_valid_url_name(request, some_number):
 @waffle_flag('foo', redirect_to='invalid_view')
 def flagged_view_with_invalid_redirect(request):
     return HttpResponse('foo')
+
+
+class BaseWaffleView(View):
+    def get(self, request, *args, **kwargs):
+        return HttpResponse('foo')
+
+
+class FlagView(WaffleFlagMixin, BaseWaffleView):
+    waffle_flag = 'foo'
+
+
+class FlagOffView(WaffleFlagMixin, BaseWaffleView):
+    waffle_flag = '!foo'
+
+
+class SampleView(WaffleSampleMixin, BaseWaffleView):
+    waffle_sample = 'foo'
+
+
+class SampleOffView(WaffleSampleMixin, BaseWaffleView):
+    waffle_sample = '!foo'
+
+
+class SwitchView(WaffleSwitchMixin, BaseWaffleView):
+    waffle_switch = 'foo'
+
+
+class SwitchOffView(WaffleSwitchMixin, BaseWaffleView):
+    waffle_switch = '!foo'

waffle/mixins.py

@@ -0,0 +1,70 @@
+from functools import partial
+
+from django.http import Http404
+
+from waffle import switch_is_active, flag_is_active, sample_is_active
+
+
+class BaseWaffleMixin(object):
+
+    def validate_waffle(self, waffle, func):
+        if waffle.startswith('!'):
+            active = not func(waffle[1:])
+        else:
+            active = func(waffle)
+        return active
+
+    def invalid_waffle(self):
+        raise Http404('Inactive waffle')
+
+
+class WaffleFlagMixin(BaseWaffleMixin):
+    """
+    Checks that as flag is active, or 404. Operates like the FBV decorator
+    waffle_flag
+    """
+
+    waffle_flag = None
+
+    def dispatch(self, request, *args, **kwargs):
+        func = partial(flag_is_active, request)
+        active = self.validate_waffle(self.waffle_flag, func)
+
+        if not active:
+            return self.invalid_waffle()
+
+        return super(WaffleFlagMixin, self).dispatch(request, *args, **kwargs)
+
+
+class WaffleSampleMixin(BaseWaffleMixin):
+    """
+    Checks that as switch is active, or 404. Operates like the FBV decorator
+    waffle_sample.
+    """
+
+    waffle_sample = None
+
+    def dispatch(self, request, *args, **kwargs):
+        active = self.validate_waffle(self.waffle_sample, sample_is_active)
+
+        if not active:
+            return self.invalid_waffle()
+
+        return super(WaffleSampleMixin, self).dispatch(request, *args, **kwargs)
+
+
+class WaffleSwitchMixin(BaseWaffleMixin):
+    """
+    Checks that as switch is active, or 404. Operates like the FBV decorator
+    waffle_switch.
+    """
+
+    waffle_switch = None
+
+    def dispatch(self, request, *args, **kwargs):
+        active = self.validate_waffle(self.waffle_switch, switch_is_active)
+
+        if not active:
+            return self.invalid_waffle()
+
+        return super(WaffleSwitchMixin, self).dispatch(request, *args, **kwargs)

waffle/tests/test_mixin.py

@@ -0,0 +1,102 @@
+from django.contrib.auth.models import AnonymousUser
+from django.http import Http404
+from django.test import RequestFactory
+
+from test_app import views
+from waffle.middleware import WaffleMiddleware
+from waffle.models import Flag, Sample, Switch
+from waffle.tests.base import TestCase
+
+
+def get(**kw):
+    request = RequestFactory().get('/foo', data=kw)
+    request.user = AnonymousUser()
+    return request
+
+
+def process_request(request, view):
+    response = view.as_view()(request)
+    return WaffleMiddleware().process_response(request, response)
+
+
+class WaffleFlagMixinTest(TestCase):
+    def setUp(self):
+        self.request = get()
+
+    def test_flag_must_be_active(self):
+        view = views.FlagView
+        self.assertRaises(Http404, process_request, self.request, view)
+
+        Flag.objects.create(name='foo', everyone=True)
+        response = process_request(self.request, view)
+        self.assertEqual(b'foo', response.content)
+
+    def test_flag_must_be_inactive(self):
+        view = views.FlagOffView
+        response = process_request(self.request, view)
+        self.assertEqual(b'foo', response.content)
+
+        Flag.objects.create(name='foo', everyone=True)
+        self.assertRaises(Http404, process_request, self.request, view)
+
+    def test_override_with_cookie(self):
+        Flag.objects.create(name='foo', percent='0.1')
+        self.request.COOKIES['dwf_foo'] = 'True'
+        response = process_request(self.request, views.FlagView)
+        self.assertEqual(b'foo', response.content)
+        self.assertIn('dwf_foo', response.cookies)
+        self.assertEqual('True', response.cookies['dwf_foo'].value)
+
+
+class WaffleSampleMixinTest(TestCase):
+    def setUp(self):
+        self.request = get()
+
+    def test_sample_must_be_active(self):
+        view = views.SampleView
+        self.assertRaises(Http404, process_request, self.request, view)
+
+        Sample.objects.create(name='foo', percent='100.0')
+        response = process_request(self.request, view)
+        self.assertEqual(b'foo', response.content)
+
+    def test_sample_must_be_inactive(self):
+        view = views.SampleOffView
+        response = process_request(self.request, view)
+        self.assertEqual(b'foo', response.content)
+
+        Sample.objects.create(name='foo', percent='100.0')
+        self.assertRaises(Http404, process_request, self.request, view)
+
+    def test_override_with_cookie(self):
+        Sample.objects.create(name='foo', percent='0.0')
+        self.request.COOKIES['dwf_foo'] = 'True'
+        self.assertRaises(Http404, process_request, self.request,
+                          views.SwitchView)
+
+
+class WaffleSwitchMixinTest(TestCase):
+    def setUp(self):
+        self.request = get()
+
+    def test_switch_must_be_active(self):
+        view = views.SwitchView
+        self.assertRaises(Http404, process_request, self.request, view)
+
+        Switch.objects.create(name='foo', active=True)
+        response = process_request(self.request, view)
+        self.assertEqual(b'foo', response.content)
+
+    def test_switch_must_be_inactive(self):
+        view = views.SwitchOffView
+        response = process_request(self.request, view)
+        self.assertEqual(b'foo', response.content)
+
+        Switch.objects.create(name='foo', active=True)
+        self.assertRaises(Http404, process_request, self.request, view)
+
+    def test_no_override_with_cookie(self):
+        Switch.objects.create(name='foo', active=False)
+        self.request.COOKIES['dwf_foo'] = 'True'
+        self.assertRaises(Http404, process_request, self.request,
+                          views.SwitchView)