#rhbase

Sometimes you may have to perform some analysis on the dataset which is stored in HBASE tables on the Hadoop cluster. Recently, I came across this situation and Revolution Analytics's package rhbase came to the rescue. Although, the tutorial given on the rhbase wiki is very well documented but there are some issue which I have faced and I thought I should create a step by step guide for suture references.

The following things are required to be installed on the server and client.

Server: Linux-Ubuntu, Hadoop, HBASE, R, Rstudio-server, thrift

Client: Browser

For this guide I assume Ubuntu, Hadoop, and HBASE are already installed and configured on the server side and there are some data tables in the HBASE database.

1. R

sudo apt-get install r-base

2. Rstudio Server

Install Rstudio server form the instructions given on the download site

3. Apache Thrift

Download apache thrift version 0.9.0 rather than 0.9.1

Install all Thrift pre-requisites

Ubuntu

$ sudo apt-get install libboost-dev libboost-test-dev libboost-program-options-dev libevent-dev automake libtool flex bison pkg-config g++ libssl-dev

CentOS5/Rhel5

$ sudo yum install automake libtool flex bison pkgconfig gcc-c++ boost-devel libevent-devel zlib-devel python-devel ruby-devel

- Build Thrfit according to instructions - Update PKG_CONFIG_PATH in bashrc by typing the following command in terminal:

sudo nano ~/.bashrc

And paste the following line at the end

export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig/

Then source the bashrc via

source ~/.bashrc

Verifiy pkg-config path is correct: Type this in terminal

pkg-config --cflags thrift

And it should return -I/usr/local/include/thrift and not something like -I/usr/local/include

Copy Thrift library

sudo cp /usr/local/lib/libthrift-0.9.0.so /usr/lib/

4. Start HBASE and Thrift server

HBASE

start-hbase.sh

Now HBASE must be running. To verify whether hadoop and related all applications are running or not and query HBASE perform the following

jps

You should see something like,

6162 DataNode

6739 TaskTracker

502 JobTracker

7029 HMaster

14867 Jps

12245 Main

5924 NameNode

7320 HRegionServer

13740 ThriftServer

6412 SecondaryNameNode

hbase shell hbase(main):003:0> list #To see list of tables hbase(main):003:0> describe('TABLE_NAME') #Small description of concerned table hbase(main):003:0> scan('TABLE_NAME') #Get content of that table

Thrift

hbase thrift start

If it throws an error then try this

hbase thrift start -threadpool

5. rhbase

Installing rhbase package generally requires 2 steps

wget https://raw.github.com/RevolutionAnalytics/rhbase/master/build/rhbase_1.2.0.tar.gz R CMD INSTALL rhbase_1.2.0.tar.gz

6. Login into Rstudio server

Type server's IP in the browser with port 8787. For example, 192.168.20.10:8787

7. Query HBASE from R

require(rhbase) hostLoc = '192.168.20.10' #Give your server IP port = 9090 #Default port for thrift service hb.init(hostLoc, port) hb.init(serialize="character") #If data in table is characters other no need for this step hb.list.tables() hb.describe.table("TABLE_NAME") data <- c() iter <- hb.scan(tablename='TABLE_NAME', startrow="1", colspec="FamilyName:") while(length(row <- iter$get(1))>0){ data <- c(data, row) }