Use metaclass to add images and links to blocks

.travis.yml

@@ -19,5 +19,6 @@ install:
   - npm -g install less@1.3.3 phantomjs
 script:
   - py.test --pep8 --cov fancypages
+  - py.test -m 'integration'
 after_success:
   - coveralls

fancypages/models/blocks/base.py

@@ -0,0 +1,44 @@
+from django.db import models
+from django.utils.translation import ugettext_lazy as _
+
+from ...assets.fields import AssetKey
+
+
+class MultiImageMeta(models.base.ModelBase):
+
+    def __init__(cls, name, bases, nmspc):
+        super(MultiImageMeta, cls).__init__(name, bases, nmspc)
+        if hasattr(cls, 'num_images'):
+            cls.add_image_fields()
+
+    def add_image_fields(cls):
+        if not getattr(cls, 'image_field_name', None):
+            cls.image_field_name = "image_%d"
+
+        for idx in range(1, cls.num_images + 1):
+            cls.add_to_class(
+                cls.image_field_name % idx,
+                AssetKey('assets.ImageAsset', verbose_name=_("Image %d" % idx),
+                         related_name="+", blank=True, null=True))
+
+
+class MultiLinkMeta(models.base.ModelBase):
+
+    def __init__(cls, name, bases, nmspc):
+        super(MultiLinkMeta, cls).__init__(name, bases, nmspc)
+        if hasattr(cls, 'num_links'):
+            cls.add_link_fields()
+
+    def add_link_fields(cls):
+        if not getattr(cls, 'link_field_name', None):
+            cls.link_field_name = "link_url_%d"
+
+        for idx in range(1, cls.num_links + 1):
+            cls.add_to_class(
+                cls.link_field_name % idx,
+                models.CharField(_("Link URL %d" % idx), max_length=500,
+                                 blank=True, null=True))
+
+
+class MultiImageLinkMeta(MultiImageMeta, MultiLinkMeta):
+    pass

fancypages/models/blocks/content.py

@@ -5,6 +5,7 @@
 from django.utils.translation import ugettext_lazy as _
 
 from ... import abstract_models
+from .base import MultiImageLinkMeta
 from ...assets.fields import AssetKey
 from ..mixins import ImageMetadataMixin
 from ...library import register_content_block
@@ -103,12 +104,12 @@ class Meta:
 
 @register_content_block
 class CarouselBlock(ContentBlock):
+    __metaclass__ = MultiImageLinkMeta
+
     name = _("Image carousel")
     code = 'carousel'
     group = _("Content")
-    num_images = 10
-    image_field_name = "image_%d"
-    link_field_name = "link_url_%d"
+    num_images = num_links = 10
     template_name = "fancypages/blocks/carouselblock.html"
 
     def get_images_and_links(self):
@@ -135,29 +136,6 @@ class Meta:
         app_label = 'fancypages'
 
 
-# generate the image field for the CarouselBlock dynamically
-# because I am lazy ;)
-for idx in range(1, CarouselBlock.num_images + 1):
-    CarouselBlock.add_to_class(
-        CarouselBlock.image_field_name % idx,
-        AssetKey(
-            'assets.ImageAsset',
-            verbose_name=_("Image %d" % idx),
-            related_name="+",
-            blank=True,
-            null=True,
-        )
-    )
-    CarouselBlock.add_to_class(
-        CarouselBlock.link_field_name % idx,
-        models.CharField(
-            _("Link URL %d" % idx),
-            max_length=500,
-            blank=True, null=True
-        )
-    )
-
-
 @register_content_block
 class PageNavigationBlock(ContentBlock):
     name = _("Page Navigation")

fancypages/test/testcases.py

@@ -1,13 +1,15 @@
 import os
+import mock
 
 from purl import URL
 
 from django.conf import settings
-from django.test import LiveServerTestCase
+from django.template import RequestContext
 from django.core.urlresolvers import reverse
 from django import VERSION as DJANGO_VERSION
 from django.core.management import call_command
 from django.db import connections, DEFAULT_DB_ALIAS
+from django.test import TestCase, LiveServerTestCase
 
 from splinter import Browser
 
@@ -20,6 +22,20 @@
 )
 
 
+class BlockTestCase(TestCase):
+
+    def setUp(self):
+        super(BlockTestCase, self).setUp()
+        self.user = factories.UserFactory.build()
+
+        self.request_context = RequestContext(mock.MagicMock())
+        self.request_context['user'] = self.user
+
+    def get_rendered_block(self, block):
+        renderer = block.get_renderer_class()(block, self.request_context)
+        return renderer.render()
+
+
 class SplinterTestCase(LiveServerTestCase):
     username = 'peter.griffin'
     email = 'peter@griffin.com'

fancypages/tests/unit/blocks/test_carousel_block.py

@@ -0,0 +1,23 @@
+from django.db.models import get_model
+from fancypages.test.testcases import BlockTestCase
+
+CarouselBlock = get_model('fancypages', 'CarouselBlock')
+
+
+class TestCarouselBlock(BlockTestCase):
+    model = CarouselBlock
+    assert_in_html = "flexslider"
+
+    def test_has_10_image_attributes(self):
+        carousel = CarouselBlock()
+        for idx in range(1, 11):
+            self.assertTrue(hasattr(carousel, carousel.image_field_name % idx))
+
+    def test_has_10_link_attributes(self):
+        carousel = CarouselBlock()
+        for idx in range(1, 11):
+            self.assertTrue(hasattr(carousel, carousel.link_field_name % idx))
+
+    def test_can_be_rendered_in_template(self):
+        html = self.get_rendered_block(CarouselBlock())
+        self.assertIn('flexslider', html)

pytest.ini

@@ -1,5 +1,5 @@
 [pytest]
-addopts = -m 'not integration'
+addopts= -m 'not integration' 
 pep8ignore=
     conftest.py ALL