The Elasticsearch REST module allows Elasticsearch APIs to be exposed over HTTP using JSON. We can perform different operations on Elasticsearch using APIs, such as monitoring the cluster health, checking nodes, indices, and shards, or creating, updating, or deleting the index. So, ideally, we can do everything using the REST-based API, which we can use to interact with Elasticsearch. We will discuss these APIs in detail later in this chapter, but for now, let's learn how to handle multiple indices if we want to interact with them simultaneously.
API conventions
Handling multiple indices
APIs can be applied to multiple indices using a list of indices, a wildcard index, or all of the indices, by using the _all notation...