XBlockAsides Hello world example

cms/djangoapps/contentstore/views/preview.py

@@ -119,6 +119,20 @@ class PreviewModuleSystem(ModuleSystem):  # pylint: disable=abstract-method
         """
         return self.wrap_xblock(block, view_name, Fragment(), context)
 
+    def layout_asides(self, block, context, frag, view_name, aside_frag_fns):
+        position_for_asides = '<!-- footer for xblock_aside -->'
+        result = Fragment()
+        result.add_frag_resources(frag)
+
+        for aside, aside_fn in aside_frag_fns:
+            aside_frag = self.wrap_aside(block, aside, view_name, aside_fn(block, context), context)
+            aside.save()
+            result.add_frag_resources(aside_frag)
+            frag.content = frag.content.replace(position_for_asides, position_for_asides + aside_frag.content)
+
+        result.add_content(frag.content)
+        return result
+
 
 class StudioPermissionsService(object):
     """

cms/lib/xblock/tagging.py

@@ -0,0 +1,92 @@
+"""
+Example implementation of Structured Tagging based on XBlockAsides
+"""
+
+from xblock.core import XBlockAside
+from xblock.fragment import Fragment
+from xblock.fields import Scope, Dict
+from xmodule.x_module import STUDENT_VIEW
+from xmodule.capa_module import CapaModule
+from abc import ABCMeta, abstractproperty
+from edxmako.shortcuts import render_to_string
+
+
+_ = lambda text: text
+
+
+class AbstractTag(object):
+    """
+    Abstract class for tags
+    """
+    __metaclass__ = ABCMeta
+
+    @abstractproperty
+    def key(self):
+        """
+        Subclasses must implement key
+        """
+        raise NotImplementedError('Subclasses must implement key')
+
+    @abstractproperty
+    def name(self):
+        """
+        Subclasses must implement name
+        """
+        raise NotImplementedError('Subclasses must implement name')
+
+    @abstractproperty
+    def allowed_values(self):
+        """
+        Subclasses must implement allowed_values
+        """
+        raise NotImplementedError('Subclasses must implement allowed_values')
+
+
+class LearningOutcomeTag(AbstractTag):
+    """
+    Particular implementation tags for learning outcomes
+    """
+    @property
+    def key(self):
+        """ Identifier for the learning outcome selector """
+        return 'learning_outcome_tag'
+
+    @property
+    def name(self):
+        """ Label for the learning outcome selector """
+        return _('Learning outcomes')
+
+    @property
+    def allowed_values(self):
+        """ Allowed values for the learning outcome selector """
+        return {'test1': 'Test 1', 'test2': 'Test 2', 'test3': 'Test 3'}
+
+
+class StructuredTagsAside(XBlockAside):
+    """
+    Aside that allows tagging blocks
+    """
+    saved_tags = Dict(help=_("Dictionary with the available tags"),
+                      scope=Scope.content,
+                      default={},)
+    available_tags = [LearningOutcomeTag()]
+
+    @XBlockAside.aside_for(STUDENT_VIEW)
+    def student_view_aside(self, block, context):
+        """
+        Display the tag selector with specific categories and allowed values,
+        depending on the context.
+        """
+        if isinstance(block, CapaModule):
+            tags = []
+            for tag in self.available_tags:
+                tags.append({
+                    'key': tag.key,
+                    'title': tag.name,
+                    'values': tag.allowed_values,
+                    'current_value': self.saved_tags.get(tag.key, None),
+                })
+            return Fragment(render_to_string('structured_tags_block.html', {'tags': tags}))
+            #return Fragment(u'<div class="xblock-render">Hello world!!!</div>')
+        else:
+            return Fragment(u'')

cms/templates/structured_tags_block.html

@@ -0,0 +1,15 @@
+<div class="xblock-render">
+    % for tag in tags:
+    <label for="problem_tags_${tag['key']}">${tag['title']}</label>:
+    <select id="problem_tags_${tag['key']}" name="problem_tags_${tag['key']}">
+        % for k,v in tag['values'].iteritems():
+            <%
+                selected = ''
+                if k == tag['current_value']:
+                    selected = 'selected'
+            %>
+            <option value="${k}" ${selected}>${v}</option>
+        % endfor
+    % endfor
+    </select>
+</div>

cms/templates/studio_xblock_wrapper.html

@@ -150,7 +150,9 @@ messages = xblock.validate().to_json()
  % endif   
 
 % if not is_root:
+    <!-- footer for xblock_aside -->
     </section>
+
     % if is_reorderable:
         </li>
     % else:

common/lib/xmodule/setup.py

@@ -44,6 +44,9 @@ XBLOCKS = [
     "vertical = xmodule.vertical_block:VerticalBlock",
     "wrapper = xmodule.wrapper_module:WrapperBlock",
 ]
+XBLOCKS_ASIDES = [
+    'tagging_aside = cms.lib.xblock.tagging:StructuredTagsAside',
+]
 
 setup(
     name="XModule",
@@ -66,6 +69,7 @@ setup(
     entry_points={
         'xblock.v1': XMODULES + XBLOCKS,
         'xmodule.v1': XMODULES,
+        'xblock_asides.v1': XBLOCKS_ASIDES,
         'console_scripts': [
             'xmodule_assets = xmodule.static_content:main',
         ],