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https://issues.apache.org/jira/browse/HADOOP-1568?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12511219
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James P. White commented on HADOOP-1568:
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The improvement comes by using a format that encodes a machine-readable schema
into HTML.
The best of these (which you may like to think of as "microformats done right")
is eRDF (Embedded RDF):
http://www.ifcx.org/wiki/EmbeddedRDF.html
In addition to easily enabling data to be extracted from the HTML, a GRDDL
header can point to an extraction (or the original in the case of RDF-to-rRDF
generation) that simply requires a GET.
I've been trying to identify a good RDF schema for file systems, but most folks
just treat file systems as resources and use RDF collection types. I'm
thinking though there may be something useful in Mozilla. Fortunately though,
thanks to RDF's open approach to schema, it doesn't really matter if you start
with a good commonly used one or not.
And since this is XHTML, there is no special library support needed that isn't
in an XML library. As the eRDF home page illusrates, a simple XSLT script is
an easy (though not necessarily the fastest) way to get data out of eRDF.
> NameNode Schema for HttpFileSystem
> ----------------------------------
>
> Key: HADOOP-1568
> URL: https://issues.apache.org/jira/browse/HADOOP-1568
> Project: Hadoop
> Issue Type: New Feature
> Components: fs
> Reporter: Chris Douglas
> Assignee: Chris Douglas
>
> This issue will track the design and implementation of (the first pass of) a
> servlet on the namenode for querying its filesystem via HTTP. The proposed
> syntax for queries and responses is as follows.
> *Query*
> {noformat}GET http://<nn>:<port>/ls.jsp[<?option>[&option]*]
> HTTP/1.1{noformat}
> Where _option_ may be any of the following query parameters:
> _path_ : String (default: '/')
> _recursive_ : boolean (default: false)
> _filter_ : String (default: none)
> *Response*
> The response will be returned as an XML document in the following format:
> {noformat}
> <listing path="..." recursive="(yes|no)" filter="..."
> time="yyyy-MM-dd hh:mm:ss UTC" version="...">
> <directory path="..."/>
> <file path="..." modified="yyyy-MM-dd hh:mm:ss" blocksize="..."
> replication="..." size="..."
> dnurl="http://dn:port/streamFile?..."/>
> </listing>
> {noformat}
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