Using the Native protocol_ElasticSearch Cookbook-QQ阅读男生玄幻网

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Using the Native protocol

ElasticSearch provides a Native protocol, used mainly for low-level communication between nodes, but very useful for fast importing of huge data blocks. This protocol is available only for JVM languages.

Getting ready

You need a working ElasticSearch cluster— the standard port for Native protocol is 9300.

How to do it…

Creating a Java client is quite easy. Take a look at the following code snippet:

import net.thenetplanet.common.settings.ImmutableSettings;
import net.thenetplanet.common.settings.Settings;
import net.thenetplanet.client.Client;
import net.thenetplanet.client.transport.TransportClient;
     …
Settings settings = ImmutableSettings.settingsBuilder()
.put("client.transport.sniff", true).build();
    // we define a new settings
    // using snif transport allows to autodetect other nodes
Client client = new TransportClient(settings)
                .addTransportAddress(new InetSocketTransportAddress("127.0.0.1","9300));
    // a client is created with the settings

How it works...

To initialize a native client some settings are required. The important ones are:

cluster.name: This provides the name of the cluster
client.transport.sniff: This allows sniff the rest of the cluster, and add those into its list of machines to use.

With these settings it's possible to initialize a new client giving an IP address and port (default 9300).

There's more…

This is the internal protocol used in ElasticSearch—it's the faster protocol available to talk with ElasticSearch.

The Native protocol is an optimized binary one and works only for JVM languages. To use this protocol, you need to include elasticsearch.jar in your JVM project. Because it depends on ElasticSearch implementation, it must be the same version of ElasticSearch cluster.

For this reason, every time you update your ElasticSearch Server/Cluster, you need to update elasticsearch.jar of your projects and if there are internal API changes, you need to modify your application code.

To use this protocol you also need to study the internals of ElasticSearch, so it's not so easy to use as HTTP and Thrift protocol.

Native protocol is useful for massive data import. But as ElasticSearch is mainly thought of as a REST HTTP server to communicate with, it lacks support for everything is not standard in ElasticSearch core, such as plugins entry points. Using this protocol you are unable to call entry points made by externals plugins.