Now that we have some data stored in Elasticsearch, we can get to work on the business requirements for this application. The first requirement is the ability to retrieve individual employee data.

This is easy in Elasticsearch. We simply execute an HTTP GET request and specify the address of the document—the index, type, and ID. Using those three pieces of information, we can return the original JSON document:

GET /megacorp/employee/1

And the response contains some metadata about the document, and John Smith’s original JSON document as the _source field:

{
  "_index" :   "megacorp",
  "_type" :    "employee",
  "_id" :      "1",
  "_version" : 1,
  "found" :    true,
  "_source" :  {
      "first_name" :  "John",
      "last_name" :   "Smith",
      "age" :         25,
      "about" :       "I love to go rock climbing",
      "interests":  [ "sports", "music" ]
  }
}

In the same way that we changed the HTTP verb from PUT to GET in order to retrieve the document, we could use the DELETE verb to delete the document, and the HEAD verb to check whether the document exists. To replace an existing document with an updated version, we just PUT it again.