Creating an HTTP Elasticsearch client

With Elasticsearch 5.x, the Elasticsearch team has provided a custom low-level HTTP client to communicate with Elasticsearch. Its main features are as follows:

• Minimal dependencies

• Load balancing across all available nodes

• Failover in the case of node failures and upon specific response codes

• Failed connection penalization (whether a failed node is retried depends on how many consecutive times it failed; the more failed attempts, the longer the client will wait before trying that same node again)

• Persistent connections

• Trace logging of requests and responses

• Optional automatic discovery of cluster nodes

Getting ready

You need an up-and-running Elasticsearch installation as we described in the Downloading and installing Elasticsearch recipe in Chapter 2, Downloading and Setup.

A Maven tool, or an IDE that natively supports it for Java programming such as Eclipse or IntelliJ IDEA, must be installed.

The code for this recipe is in the chapter_14/http_es_client directory...