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HBASE-10346 Add Documentation for stateless scanner (Vandana Ayyalasomayajula) 

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1559266 13f79535-47bb-0310-9956-ffa450edef68
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ndimiduk 2014-01-17 22:01:23 +00:00
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hbase-server/src/main/java/org/apache/hadoop/hbase/rest/package.html
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@ -52,6 +52,7 @@ This package provides a RESTful Web service front end for HBase.
<li><a href="#operation_scanner_create">Scanner Creation</a></li>
<li><a href="#operation_scanner_next">Scanner Get Next</a></li>
<li><a href="#operation_scanner_delete">Scanner Deletion</a></li>
<li><a href="#operation_stateless_scanner">Stateless scanner</a></li>
</ol>
<li><a href="#xmlschema">XML Schema</a></li>
<li><a href="#pbufschema">Protobufs Schema</a></li>
@ -1184,6 +1185,206 @@ Content-Length: 0<br>
</blockquote>
<p>
<a name="operation_stateless_scanner">
<h3>Stateless Scanner</h3>
</a>
<pre>
GET /&lt;table&gt;/&lt;optional_row_prefix&gt;*?&lt;scan_parameters&gt;
</pre>
<p align="justify">
The current scanner API expects clients to restart scans if there is a REST server failure in the midst. The stateless
does not store any state related to scan operation and all the parameters are specified as query parameters.
<p>
<p>
The following are the scan parameters
<ol>
<li>startrow - The start row for the scan.</li>
<li>endrow - The end row for the scan.</li>
<li>columns - The columns to scan.</li>
<li>starttime, endtime - To only retrieve columns within a specific range of version timestamps,both start and end time must be specified.</li>
<li>maxversions - To limit the number of versions of each column to be returned.</li>
<li>batchsize - To limit the maximum number of values returned for each call to next().</li>
<li>limit - The number of rows to return in the scan operation.</li>
</ol>
<p>
<p>
More on start row, end row and limit parameters.
<ol>
<li>If start row, end row and limit not specified, then the whole table will be scanned.</li>
<li>If start row and limit (say N) is specified, then the scan operation will return N rows from the start row specified.</li>
<li>If only limit parameter is specified, then the scan operation will return N rows from the start of the table.</li>
<li>If limit and end row are specified, then the scan operation will return N rows from start of table till the end row. If the end
row is reached before N rows ( say M and M &lt; N ), then M rows will be returned to the user.</li>
<li>If start row, end row and limit (say N ) are specified and N &lt; number of rows between start row and end row, then N rows from
start row will be returned to the user. If N &gt; (number of rows between start row and end row (say M), then M number of rows
will be returned to the user.</li>
</ol>
<p>
<p><b>Examples</b><p>
<p>
<blockquote>
<pre>
Lets say we have a table with name "ExampleScanner". On Hbase shell,
&gt;&gt; scan 'ExampleScanner'
ROW COLUMN+CELL
testrow1 column=a:1, timestamp=1389900769772, value=testvalue-a1
testrow1 column=b:1, timestamp=1389900780536, value=testvalue-b1
testrow2 column=a:1, timestamp=1389900823877, value=testvalue-a2
testrow2 column=b:1, timestamp=1389900818233, value=testvalue-b2
testrow3 column=a:1, timestamp=1389900847336, value=testvalue-a3
testrow3 column=b:1, timestamp=1389900856845, value=testvalue-b3
</pre>
<ul>
<li>
<pre>
<b>Scanning the entire table in json</b>
curl -H "Accept: application/json" https://localhost:8080/ExampleScanner/*
</pre>
<p>
<tt>
{"Row":[{"key":"dGVzdHJvdzE=","Cell":[{"column":"YTox","timestamp":1389900769772,"$":"dGVzdHZhbHVlLWEx"},<br>
{"column":"Yjox","timestamp":1389900780536,"$":"dGVzdHZhbHVlLWIx"}]},{"key":"dGVzdHJvdzI=","Cell":[{"column":<br>
"YTox","timestamp":1389900823877,"$":"dGVzdHZhbHVlLWEy"}{"column":"Yjox",<br>
"timestamp":1389900818233,"$":"dGVzdHZhbHVlLWIy"}]},{"key":"dGVzdHJvdzM=","Cell":[{"column":"YTox",<br>
"timestamp":1389900847336,"$":"dGVzdHZhbHVlLWEz"},{"column":"Yjox","timestamp":1389900856845,"$":"dGVzdHZhbHVlLWIz"}]}]}<br>
<br>
</tt>
<p>
</li>
<li>
<pre>
<b>Scanning the entire table in XML</b>
curl -H "Content-Type: text/xml" https://localhost:8080/ExampleScanner/*
</pre>
<p>
<tt>
&lt;?xml version="1.0" encoding="UTF-8" standalone="yes"?&gt;&lt;CellSet&gt;&lt;Row key="dGVzdHJvdzE="&gt;<br>
&lt;Cell column="YTox" timestamp="1389900769772"&gt;dGVzdHZhbHVlLWEx&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900780536"&gt;dGVzdHZhbHVlLWIx&lt;/Cell&gt;&lt;/Row&gt;&lt;Row key="dGVzdHJvdzI="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900823877"&gt;dGVzdHZhbHVlLWEy&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900818233"&gt;dGVzdHZhbHVlLWIy&lt;/Cell&gt;&lt;/Row&gt;&lt;Row key="dGVzdHJvdzM="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900847336"&gt;dGVzdHZhbHVlLWEz&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900856845"&gt;dGVzdHZhbHVlLWIz&lt;/Cell&gt;&lt;/Row&gt;&lt;/CellSet&gt;<br>
</tt>
<p>
</li>
<li>
<pre>
<b>Scanning the entire table in binary</b>
curl -H "Accept: application/protobuf" https://localhost:8080/ExampleScanner/*
^@Ì
B
^Htestrow1^R^Z^R^Ca:1^XìÓªä¹("^Ltestvalue-a1^R^Z^R^Cb:1^Xø§«ä¹("^Ltestvalue-b1
B
^Htestrow2^R^Z^R^Ca:1^XÅú­ä¹("^Ltestvalue-a2^R^Z^R^Cb:1^X¹Î­ä¹("^Ltestvalue-b2
B
^Htestrow3^R^Z^R^Ca:1^X豯ä¹("^Ltestvalue-a3^R^Z^R^Cb:1^X<8d>ü¯ä¹("^Ltestvalue-b3
</pre>
</li>
<li>
<pre>
<b>Scanning the first row of table</b>
curl -H "Content-Type: text/xml" https://localhost:8080/ExampleScanner/*?limit=1
</pre>
<p>
<tt>
&lt;?xml version="1.0" encoding="UTF-8" standalone="yes"?&gt;&lt;CellSet&gt;&lt;Row key="dGVzdHJvdzE="&gt;<br>
&lt;Cell column="YTox" timestamp="1389900769772"&gt;dGVzdHZhbHVlLWEx&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900780536"&gt;dGVzdHZhbHVlLWIx&lt;/Cell&gt;&lt;/Row>&lt;/CellSet&gt;<br>
</tt>
<p>
</li>
<li>
<pre>
<b>Scanning a given column of table</b>
curl -H "Content-Type: text/xml" https://localhost:8080/ExampleScanner/*?columns=a:1
</pre>
<p>
<tt>
&lt;?xml version="1.0" encoding="UTF-8" standalone="yes"?&gt;&lt;CellSet&gt;&lt;Row key="dGVzdHJvdzE="&gt;<br>
&lt;Cell column="YTox" timestamp="1389900769772"&gt;dGVzdHZhbHVlLWEx&lt;/Cell&gt;&lt;/Row&gt;&lt;Row key="dGVzdHJvdzI="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900823877"&gt;dGVzdHZhbHVlLWEy&lt;/Cell&gt;&lt;/Row&gt;&lt;Row key="dGVzdHJvdzM="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900847336"&gt;dGVzdHZhbHVlLWEz&lt;/Cell&gt;&lt;/Row&gt;&lt;/CellSet&gt;<br>
</tt>
<p>
</li>
<li>
<pre>
<b>Scanning more than one column of table</b>
curl -H "Content-Type: text/xml" https://localhost:8080/ExampleScanner/*?columns=a:1,b:1
</pre>
<p>
<tt>
&lt;?xml version="1.0" encoding="UTF-8" standalone="yes"?&gt;&lt;CellSet&gt;&lt;Row key="dGVzdHJvdzE="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900769772"&gt;dGVzdHZhbHVlLWEx&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900780536"&gt;dGVzdHZhbHVlLWIx&lt;/Cell&gt;&lt;/Row&gt;&lt;Row key="dGVzdHJvdzI="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900823877"&gt;dGVzdHZhbHVlLWEy&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900818233"&gt;dGVzdHZhbHVlLWIy&lt;/Cell&gt;&lt;/Row&gt;&lt;Row key="dGVzdHJvdzM="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900847336"&gt;dGVzdHZhbHVlLWEz&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900856845"&gt;dGVzdHZhbHVlLWIz&lt;/Cell&gt;&lt;/Row&gt;&lt;/CellSet&gt;<br>
</tt>
<p>
</li>
<li>
<pre>
<b>Scanning table with start row and limit</b>
curl -H "Content-Type: text/xml" https://localhost:8080/ExampleScanner/*?startrow=testrow1&amp;limit=2
</pre>
<p>
<tt>
&lt;?xml version="1.0" encoding="UTF-8" standalone="yes"?&gt;&lt;CellSet&gt;&lt;Row key="dGVzdHJvdzE="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900769772"&gt;dGVzdHZhbHVlLWEx&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900780536"&gt;dGVzdHZhbHVlLWIx&lt;/Cell&gt;&lt;/Row&gt;&lt;Row key="dGVzdHJvdzI="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900823877"&gt;dGVzdHZhbHVlLWEy&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900818233"&gt;dGVzdHZhbHVlLWIy&lt;/Cell&gt;&lt;/Row&gt;&lt;/CellSet&gt;<br>
</tt>
<p>
</li>
<li>
<pre>
<b>Scanning with start and end time</b>
curl -H "Content-Type: text/xml" https://localhost:8080/ExampleScanner/*?starttime=1389900769772&amp;endtime=1389900800000
</pre>
<p>
<tt>
&lt;?xml version="1.0" encoding="UTF-8" standalone="yes"?&gt;&lt;CellSet&gt;&lt;Row key="dGVzdHJvdzE="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900769772"&gt;dGVzdHZhbHVlLWEx&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900780536"&gt;dGVzdHZhbHVlLWIx&lt;/Cell&gt;&lt;/Row&gt;&lt;/CellSet&gt;<br>
</tt>
<p>
</li>
<li>
<pre>
<b>Scanning with row prefix</b>
curl -H "Content-Type: text/xml" https://localhost:8080/ExampleScanner/test*
</pre>
<p>
<tt>
&lt;?xml version="1.0" encoding="UTF-8" standalone="yes"?&gt;&lt;CellSet&gt;&lt;Row key="dGVzdHJvdzE="&gt;<br>
&lt;Cell column="YTox" timestamp="1389900769772"&gt;dGVzdHZhbHVlLWEx&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900780536"&gt;dGVzdHZhbHVlLWIx&lt;/Cell&gt;&lt;/Row&gt;&lt;Row key="dGVzdHJvdzI="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900823877"&gt;dGVzdHZhbHVlLWEy&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900818233"&gt;dGVzdHZhbHVlLWIy&lt;/Cell&gt;&lt;/Row&gt;&lt;Row key="dGVzdHJvdzM="&gt;&lt;<br>
Cell column="YTox" timestamp="1389900847336"&gt;dGVzdHZhbHVlLWEz&lt;/Cell&gt;&lt;Cell column="Yjox"<br>
timestamp="1389900856845"&gt;dGVzdHZhbHVlLWIz&lt;/Cell&gt;&lt;/Row&gt;&lt;/CellSet&gt;<br>
</tt>
<p>
</li>
</ul>
</blockquote>
</p>
<p>
<a name="xmlschema">
<h2>XML Schema</h2>