{
  "_index" : "customer",
  "_type" : "_doc",
  "_id" : "1",
  "_version" : 1,
  "_seq_no" : 1,
  "_primary_term" : 1,
  "found" : true,
  "_source" : {
    "name" : "ajay"
  }
}

PUT /customer/_doc/1
{
  "firstname": "ajay",
  "lastname": "tanwar"

}

{
  "_index" : "customer",
  "_type" : "_doc",
  "_id" : "1",
  "_version" : 2,
  "_seq_no" : 2,
  "_primary_term" : 1,
  "found" : true,
  "_source" : {
    "firstname" : "ajay",
    "lastname" : "tanwar"
  }
}

POST /customer/_doc/1/_update
{
  "doc":{
      "firstname": "ajay",
      "lastname": "tanwar"
  }
}