Class URLMetaIndexingFilter

  • All Implemented Interfaces:
    Configurable, IndexingFilter, Pluggable

    public class URLMetaIndexingFilter
    extends Object
    implements IndexingFilter
    This is part of the URL Meta plugin. It is designed to enhance the NUTCH-655 patch, by doing two things: 1. Meta Tags that are supplied with your Crawl URLs, during injection, will be propagated throughout the outlinks of those Crawl URLs. 2. When you index your URLs, the meta tags that you specified with your URLs will be indexed alongside those URLs--and can be directly queried, assuming you have done everything else correctly. The flat-file of URLs you are injecting should, per NUTCH-655, be tab-delimited in the form of: [www.url.com]\t[key1]=[value1]\t[key2]=[value2]...[keyN]=[valueN] Be aware that if you collide with keywords that are already in use (such as nutch.score/nutch.fetchInterval) then you are in for some unpredictable behavior. Furthermore, in your nutch-site.xml config, you must specify that this plugin is to be used (1), as well as what (2) Meta Tags it should actively look for. This does not mean that you must use these tags for every URL, but it does mean that you must list _all_ of meta tags that you have specified. If you want them to be propagated and indexed, that is. 1. As of Nutch 1.2, the property "plugin.includes" looks as follows: <value>protocol-http|urlfilter-regex|parse-(text|html|js|tika|rss)|index -(basic|anchor)|query-(basic|site|url)|response-(json|xml)|summary-basic |scoring-opic|urlnormalizer-(pass|regex|basic)</value> You must change "index-(basic|anchor)" to "index-(basic|anchor|urlmeta)", in order to call this plugin. 2. You must also specify the property "urlmeta.tags", who's values are comma-delimited <value>key1, key2, key3</value> TODO: It may be ideal to offer two separate properties, to specify what gets indexed versus merely propagated.