Add Twitter Cards metadata

CHANGES.rst

@@ -6,6 +6,9 @@ There's a frood who really knows where his towel is.
 2.4.2 (unreleased)
 ^^^^^^^^^^^^^^^^^^
 
+- Add Twitter Cards metadata (closes `#65`_).
+  [rodfersou]
+
 - Use Plone's registry instead of the ``portal_properties`` tool to store package configuration (closes `#1`_).
   [hvelarde]
 
@@ -283,3 +286,4 @@ There's a frood who really knows where his towel is.
 .. _`#38`: https://github.com/collective/sc.social.like/issues/38
 .. _`#39`: https://github.com/collective/sc.social.like/issues/39
 .. _`#56`: https://github.com/collective/sc.social.like/issues/56
+.. _`#65`: https://github.com/collective/sc.social.like/issues/65

sc/social/like/plugins/facebook/browser.py

@@ -44,6 +44,10 @@ def __init__(self, context, request):
         self.image = get_content_image(context, width=1200, height=630)
         self.typebutton  # XXX: needed to initialize self.width
 
+    def metadata_enabled(self):
+        """Disable metadata on Plone 5"""
+        return not api.env.plone_version().startswith('5')
+
     def fbjs(self):
         js_source = """
     (function() {

sc/social/like/plugins/facebook/templates/metadata.pt

@@ -1,4 +1,4 @@
-<tal:fb>
+<tal:fb condition="view/metadata_enabled">
   <meta property="og:site_name" tal:attributes="content view/portal_title" />
   <meta property="og:url" tal:attributes="content view/url" />
   <meta property="og:type" tal:attributes="content view/type" />

sc/social/like/plugins/twitter/browser.py

@@ -6,6 +6,7 @@
 from Products.Five.browser.pagetemplatefile import ViewPageTemplateFile
 from Products.PythonScripts.standard import url_quote
 from sc.social.like.interfaces import ISocialLikeSettings
+from sc.social.like.utils import get_content_image
 from sc.social.like.utils import get_language
 from urllib import urlencode
 from zope.component import getMultiAdapter
@@ -22,6 +23,8 @@ class PluginView(BrowserView):
 
     def __init__(self, context, request):
         self.context = context
+        self.title = context.title
+        self.description = context.Description()
         self.request = request
         # FIXME: the following could rise unexpected exceptions
         #        move it to a new setup() method
@@ -33,6 +36,7 @@ def __init__(self, context, request):
         self.portal_title = self.portal_state.portal_title()
         self.url = context.absolute_url()
         self.language = get_language(context)
+        self.image = get_content_image(context)
         self.urlnoscript = (
             u'http://twitter.com/home?status=' +
             url_quote(u'{0} - {1} via {2}'.format(
@@ -42,6 +46,10 @@ def __init__(self, context, request):
             )
         )
 
+    def metadata_enabled(self):
+        """Disable metadata on Plone 5"""
+        return not api.env.plone_version().startswith('5')
+
     @property
     def typebutton(self):
         record = ISocialLikeSettings.__identifier__ + '.typebutton'
@@ -68,3 +76,10 @@ def share_link(self):
 
         url = 'https://twitter.com/intent/tweet?' + urlencode(params)
         return url
+
+    def image_url(self):
+        """ Return url to image
+        """
+        img = self.image
+        if img:
+            return img.url

sc/social/like/plugins/twitter/templates/metadata.pt

@@ -0,0 +1,7 @@
+<tal:twitter condition="view/metadata_enabled">
+  <meta name="twitter:card" content="summary_large_image" />
+  <meta name="twitter:image" tal:attributes="content view/image_url" tal:condition="view/image_url" />
+  <meta name="twitter:site" tal:attributes="content string:@${view/via}" />
+  <meta name="twitter:title" tal:attributes="content view/title" />
+  <meta name="twitter:description" tal:attributes="content view/description" />
+</tal:twitter>

sc/social/like/tests/api_hacks.py

@@ -0,0 +1,15 @@
+# -*- coding: utf-8 -*-
+"""Hacks to work around API inconsistencies between Archetypes and Dexterity."""
+
+
+def set_image_field(obj, image, content_type):
+    """Set image field in object on both, Archetypes and Dexterity."""
+    from plone.namedfile.file import NamedBlobImage
+    try:
+        obj.setImage(image)  # Archetypes
+    except AttributeError:
+        # Dexterity
+        data = image if type(image) == str else image.getvalue()
+        obj.image = NamedBlobImage(data=data, contentType=content_type)
+    finally:
+        obj.reindexObject()

sc/social/like/tests/test_plugin_twitter.py

@@ -1,11 +1,14 @@
 # -*- coding: utf-8 -*-
+from plone import api
 from plone.app.testing import setRoles
 from plone.app.testing import TEST_USER_ID
 from plone.registry.interfaces import IRegistry
 from sc.social.like.interfaces import ISocialLikeLayer
 from sc.social.like.interfaces import ISocialLikeSettings
 from sc.social.like.plugins.interfaces import IPlugin
 from sc.social.like.testing import INTEGRATION_TESTING
+from sc.social.like.testing import load_image
+from sc.social.like.tests.api_hacks import set_image_field
 from zope.component import getUtilitiesFor
 from zope.component import getUtility
 from zope.interface import alsoProvides
@@ -62,10 +65,38 @@ def setUp(self):
         self.plugins = dict(getUtilitiesFor(IPlugin))
         self.plugin = self.plugins[name]
 
+        with api.env.adopt_roles(['Manager']):
+            self.image = api.content.create(
+                self.portal, 'Image', id='test-image')
+
+        set_image_field(self.image, load_image(1024, 768), 'image/png')
+
     def setup_content(self, portal):
         portal.invokeFactory('Document', 'my-document')
         self.document = portal['my-document']
 
+    def test_plugin_view_metadata(self):
+        plugin = self.plugin
+        image = self.image
+        plugin_view = plugin.view()
+        view = image.restrictedTraverse(plugin_view)
+        view.title = 'Twitter Title'
+        view.description = 'Twitter Description'
+        record = ISocialLikeSettings.__identifier__ + '.twitter_username'
+        api.portal.set_registry_record(record, 'plone')
+
+        metadata = view.metadata()
+        self.assertIn(
+            '<meta name="twitter:card" content="summary_large_image" />', metadata)
+        self.assertIn(
+            '<meta name="twitter:image" content="http://nohost/plone/test-image/@@images', metadata)
+        self.assertIn(
+            '<meta name="twitter:site" content="@plone" />', metadata)
+        self.assertIn(
+            '<meta name="twitter:title" content="Twitter Title" />', metadata)
+        self.assertIn(
+            '<meta name="twitter:description" content="Twitter Description" />', metadata)
+
     def test_plugin_view_html(self):
         plugin = self.plugin
         document = self.document

setup.py

@@ -67,6 +67,7 @@
               'plone.browserlayer',
               'plone.app.robotframework',
               'plone.app.testing [robot] >=4.2.2',
+              'plone.namedfile [blobs]',
               'robotsuite',
           ],
           'develop': ['docutils'],