Define a link element within an app:category to specify links to category descriptions, etc

Note: The text of this proposal builds off of that proposed by PaceMediaEntries3




Just looking to close another as-yet still open issue. In prior discussions, we weren't able to come to agreement on the format used to represent a categories list, although many liked the general idea of using APP to manage the list of categories. This pace punts on that issue by allowing app:collection to contain zero or more atom:link elements and defining a "categories" link relation. An introspection file would then just reference some kind of resource listing the categories without actually going through the work of defining the format. This approach has the side effect of being useful for linking other types of things to the collection as well (e.g. archives, templates, user lists, etc)


7.1 Example

<?xml version="1.0" encoding='utf-8'?>
<service xmlns=""
  <workspace title="Main Site" > 
      title="My Blog Entries" 
        href="" />
      href="" >
  <workspace title="Side Bar Blog">
    <collection title="Remaindered Links" 
      href="" />

This Introspection Document describes two workspaces. The first, called 
"Main Site", has two collections called "My Blog Entries" and "Pictures" 
whose URIs are "" and "" 
respectively. The "Pictures" includes an accept element indicating that
client may post binary image files to to collection to create new entries.
Entries with associated media resources are discussed in section 8.3.

The "My Blog Entries" collection contains a single link element referencing
an IRI where a listing of this collection's categories may be found.

The second workspace is called "Side Bar Blog" and has a single collection 
called "Remaindered Links" whose collection URI is "".

Section 7.2.3:

The "app:collection" describes an Atom Protocol collection. The app:collection element MAY contain 
one "app:accept" element and zero or more "atom:link" elements.

appCollection =
   element app:collection {
      attribute title { text },
      attribute href { text },
      ( appAccept?,
        & extensionElement* )

The "app:collection" element MAY appear as a child of an atom:feed or atom:source 
element to identify the collection to which new entries may be added to the feed

Add section 7.2.5

7.2.5 Collection links

The "app:collection" element MAY contain zero or more atom:link elements.  Each 
link defines a relationship between the collection and a Web resource.

This specification adds a "categories" link relation to the IANA Registry of 
Link Relations [RFC4287].  The IRI specified by the href attribute of a 
"categories" link relation identifies a resource that defines which categories
clients may be assigned to entries contained by the collection.