Hi ,
I know that this is more cascading related issue but may be someone
faced with the same problem or know a another implementation of cascading
hbase Tap which support TableInputFormat.
I faced with a problem reading from hbase.
I took https://github.com/taykey/cascading.hbase since this
fork support TableInputFormat.
it should to solve the issue that cascading doesn't support
new API
I created subclass of TableInputFormatBase.java (https://
github.com/taykey/cascading.hbase/blob/master/src/main/java/org/apache/
hadoop/hbase/mapred/TableInputFormatBase.java)
public class CustomTableInputFormat extends TableInputFormatBase
implements JobConfigurable {
public void configure(JobConf job) {
String tableName = "hbase_table1";
String row = "1000002:2005476:29";
String cf = "cf";
HTable exampleTable = null;
try {
exampleTable = new HTable(HBaseConfiguration.create(job),
Bytes.toBytes(tableName));
} catch (IOException e) {
e.printStackTrace(); //To change body of catch statement
use File | Settings | File Templates.
}
// mandatory
setHTable(exampleTable);
byte[][] inputColumns = new byte[][]{Bytes.toBytes(cf)};
// mandatory
setInputColumns(inputColumns);
//Filter binaryPrefixFilter = new
RowFilter(CompareFilter.CompareOp.EQUAL , new
BinaryPrefixComparator(Bytes.toBytes(row)));
// optional
//setRowFilter(binaryPrefixFilter);
}
Using this class I can read from hbase , but I need a Filter
functionality ( last 3 commented lines lines of
CustomTableInputFormat). In case I try to read from hbase using Filter
( if I uncomment binaryPrefixFilter) I got a rows that had to be
filtered out. It is looks like filter didn't get any effect.
Questions:
1. Does someone succeeded to read from hbase using cascading using
TableInputFormat? I looked thru all forks and didn't find any project
except https://github.com/taykey/cascading.hbase.If yes please share
your experience.
2. Is CustomTableInputFormat a correct way to define RowFilter?
3. I am going to debug hbase server . What is the best practice to debug
it? Is it a good Idea to run hbase locally? Which classes , packages
is responsible for configuration , execution Filter on Hbase server.
Thanks in advance.
Oleg.
