Using the Thrift protocol

Thrift is an interface definition language, initially developed by Facebook, used to define and create services. This protocol is now in the Apache Software Foundation.

Its usage is similar to HTTP, but it bypasses the limit of HTTP protocol (latency, handshake, and so on) and it's faster.

Getting ready

You need a working ElasticSearch cluster with the thrift plugin installed (https://github.com/elasticsearch/elasticsearch-transport-thrift/) the standard port for thrift protocol is 9500.

How to do it…

In java using ElasticSearch generated classes, creating a client is quite easy as shown in the following code snippet:

import org.apache.thrift.protocol.TBinaryProtocol;
import org.apache.thrift.protocol.TProtocol;
import org.apache.thrift.transport.TSocket;
import org.apache.thrift.transport.TTransport;
import org.apache.thrift.transport.TTransportException;
import org.elasticsearch.thrift.*;


TTransport transport = new TSocket("127.0.0.1", 9500);
TProtocol protocol = new TBinaryProtocol(transport);
Rest.Client client = new Rest.Client(protocol);
transport.open();

How it works…

To initialize a connection, first we need to open a socket transport. This is done with the TSocket (host/port), using the ElasticSearch thrift standard port 9500.

Then the Socket Transport Protocol must be encapsulated in a Binary Protocol—this is done with the TBinaryProtocol (transport).

Now, a client can be initialized by passing the protocol. The Rest-Client and other utilities classes are generated by elasticsearch.thrift, and live in the org.elasticsearch.thrift namespace.

To have a fully working client, we must open the socket (transport.open()).

At the end of program, we should clean the socket closing it (transport.close()).

There's more...

Some drivers to connect to ElasticSearch provide a simple to use API to interact with thrift without the boulder that this protocol needs.

For advanced usage, I suggest the use of the Thrift protocol to bypass some problems related with HTTP limits. They are as follows:

• The number of simultaneous connections required in HTTP—thrift transport is less resource angry

• The network traffic is light reduced to its binary nature

A big advantage of this protocol is that on server side it wraps the REST entry points so it can be also used with calls provided by external REST plugins.

See also

• For more details on Thrift, visit the Wikipedia page at http://en.wikipedia.org/wiki/Apache_Thrift

• For a complete reference of Thrift ElasticSearch plugin, the official documentation is available at https://github.com/elasticsearch/elasticsearch-transport-thrift/