Proposal Tag Data API

Abstract

Make tag statistics data available via a simple XML format so that other applications can access our tag data.

Requirements

Requirements satisfied by this proposal:

• Make tag statistics available in XML format
• Provide name, tag frequency and view URI for each tag
• Provide weblog specific tag data
• Provide site-wide tag data

Issues

Issues to be considered

• If possible, don't invent new format

Design

URIs to be supported

• /roller-services/tagdata - get tag data for entire site
• /roller-services/tagdata/weblogs/<handle> - get tag data for specific weblog

Request parameters supported:

• page: page number of results to be returned
• prefix: only return tags that start with this string
• format: format to be returned 'xml' for Atom categories, 'json' for JSON

New classes to be created

• TagDataServlet: New Servlet that returns tag data
• TagDataCache: New cache to be used by Servlet to cache tag content

Format to be returned

Instead of inventing a new format, return tag data in Atom protocol Categories format and add a couple of extension elements to hold tag frequency and view URI. If there are a large number of tags, server can use the <atom:link> element to specify a next and previous URI for paging. For example:

<categories fixed="no" 
xmlns="http://www.w3.org/2007/app" 
xmlns:atom="http://www.w3.org/2005/Atom" 
xmlns:tagdata="http://roller.apache.org/ns/tagdata">

   <atom:category term="java" tagdata:frequency="2"    
      tagdata:href="http://localhost:8080/roller/myblog/tags/java" />
   <atom:category term="monkey" tagdata:frequency="1" 
      tagdata:href="http://localhost:8080/roller/myblog/tags/monkey" />
   <atom:category term="monkeys" tagdata:frequency="1" 
      tagdata:href="http://localhost:8080/roller/myblog/tags/monkeys" />   
   <atom:category term="music" tagdata:frequency="1" 
      tagdata:href="http://localhost:8080/roller/myblog/tags/music" />

   <atom:link rel="next" 
      href="http://localhost:8080/roller/roller-services/tagdata/weblog/myblog/?page=1" />

</categories>

Comments

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