Merge pull request #1464 from MITx/bug/bug161

On first request for handouts, create the db record. (bug 160)

cms/djangoapps/contentstore/module_info_model.py

-import logging
 from static_replace import replace_static_urls
 from xmodule.modulestore.exceptions import ItemNotFoundError
 from xmodule.modulestore import Location
-from xmodule.modulestore.django import modulestore
-from lxml import etree
-import re
-from django.http import HttpResponseBadRequest, Http404
+from django.http import Http404
 
 
 def get_module_info(store, location, parent_location=None, rewrite_static_links=False):
-  try:
-    if location.revision is None:
-        module = store.get_item(location)
-    else:
-        module = store.get_item(location)
-  except ItemNotFoundError:
-    raise Http404
+    try:
+        if location.revision is None:
+            module = store.get_item(location)
+        else:
+            module = store.get_item(location)
+    except ItemNotFoundError:
+        # create a new one
+        template_location = Location(['i4x', 'edx', 'templates', location.category, 'Empty'])
+        module = store.clone_item(template_location, location)
 
-  data = module.definition['data']
-  if rewrite_static_links:
-    data = replace_static_urls(
-        module.definition['data'],
-        None,
-        course_namespace=Location([
-            module.location.tag,
-            module.location.org,
-            module.location.course,
+    data = module.definition['data']
+    if rewrite_static_links:
+        data = replace_static_urls(
+            module.definition['data'],
             None,
-            None
-        ])
-    )
+            course_namespace=Location([
+                module.location.tag,
+                module.location.org,
+                module.location.course,
+                None,
+                None
+            ])
+        )
 
-  return {
+    return {
         'id': module.location.url(),
         'data': data,
         'metadata': module.metadata
@@ -39,58 +37,56 @@ def get_module_info(store, location, parent_location=None, rewrite_static_links=
 
 
 def set_module_info(store, location, post_data):
-  module = None
-  isNew = False
-  try:
-    if location.revision is None:
-        module = store.get_item(location)
-    else:
-        module = store.get_item(location)
-  except:
-    pass
+    module = None
+    try:
+        if location.revision is None:
+            module = store.get_item(location)
+        else:
+            module = store.get_item(location)
+    except:
+        pass
 
-  if module is None:
-    # new module at this location
-    # presume that we have an 'Empty' template
-    template_location = Location(['i4x', 'edx', 'templates', location.category, 'Empty'])
-    module = store.clone_item(template_location, location)
-    isNew = True
+    if module is None:
+        # new module at this location
+        # presume that we have an 'Empty' template
+        template_location = Location(['i4x', 'edx', 'templates', location.category, 'Empty'])
+        module = store.clone_item(template_location, location)
 
-  if post_data.get('data') is not None:
-      data = post_data['data']
-      store.update_item(location, data)
+    if post_data.get('data') is not None:
+        data = post_data['data']
+        store.update_item(location, data)
 
-  # cdodge: note calling request.POST.get('children') will return None if children is an empty array
-  # so it lead to a bug whereby the last component to be deleted in the UI was not actually
-  # deleting the children object from the children collection
-  if 'children' in post_data and post_data['children'] is not None:
-      children = post_data['children']
-      store.update_children(location, children)
+    # cdodge: note calling request.POST.get('children') will return None if children is an empty array
+    # so it lead to a bug whereby the last component to be deleted in the UI was not actually
+    # deleting the children object from the children collection
+    if 'children' in post_data and post_data['children'] is not None:
+        children = post_data['children']
+        store.update_children(location, children)
 
-  # cdodge: also commit any metadata which might have been passed along in the
-  # POST from the client, if it is there
-  # NOTE, that the postback is not the complete metadata, as there's system metadata which is
-  # not presented to the end-user for editing. So let's fetch the original and
-  # 'apply' the submitted metadata, so we don't end up deleting system metadata
-  if post_data.get('metadata') is not None:
-      posted_metadata = post_data['metadata']
-
-      # update existing metadata with submitted metadata (which can be partial)
-      # IMPORTANT NOTE: if the client passed pack 'null' (None) for a piece of metadata that means 'remove it'
-      for metadata_key in posted_metadata.keys():
-
-          # let's strip out any metadata fields from the postback which have been identified as system metadata
-          # and therefore should not be user-editable, so we should accept them back from the client
-          if metadata_key in module.system_metadata_fields:
-              del posted_metadata[metadata_key]
-          elif posted_metadata[metadata_key] is None:
-              # remove both from passed in collection as well as the collection read in from the modulestore
-              if metadata_key in module.metadata:
-                  del module.metadata[metadata_key]
-              del posted_metadata[metadata_key]
-
-      # overlay the new metadata over the modulestore sourced collection to support partial updates
-      module.metadata.update(posted_metadata)
-
-      # commit to datastore
-      store.update_metadata(location, module.metadata)
+    # cdodge: also commit any metadata which might have been passed along in the
+    # POST from the client, if it is there
+    # NOTE, that the postback is not the complete metadata, as there's system metadata which is
+    # not presented to the end-user for editing. So let's fetch the original and
+    # 'apply' the submitted metadata, so we don't end up deleting system metadata
+    if post_data.get('metadata') is not None:
+        posted_metadata = post_data['metadata']
+        
+        # update existing metadata with submitted metadata (which can be partial)
+        # IMPORTANT NOTE: if the client passed pack 'null' (None) for a piece of metadata that means 'remove it'
+        for metadata_key in posted_metadata.keys():
+        
+            # let's strip out any metadata fields from the postback which have been identified as system metadata
+            # and therefore should not be user-editable, so we should accept them back from the client
+            if metadata_key in module.system_metadata_fields:
+                del posted_metadata[metadata_key]
+            elif posted_metadata[metadata_key] is None:
+                # remove both from passed in collection as well as the collection read in from the modulestore
+                if metadata_key in module.metadata:
+                    del module.metadata[metadata_key]
+                del posted_metadata[metadata_key]
+        
+        # overlay the new metadata over the modulestore sourced collection to support partial updates
+        module.metadata.update(posted_metadata)
+        
+        # commit to datastore
+        store.update_metadata(location, module.metadata)