hmalphettes / elasticsearch-lang-javascript-nashorn

Nashorn for Elasticsearch

Elasticsearch Nashorn Language Plugin

This plugin extends Elasticsearch with the script language Nashorn, the implementation of ECMAScript-262 Edition 5.1 ("Javascript") for the Java 8 VM.

The integration is implemented by JSR 223. It should be easy to reuse the source code of this plugin as a basis to extend Elasticsearch scripting by other JSR 223 languages.

Installation

Prerequisites

• Elasticsearch 1.0.0+
• Java 8

ES version	Plugin	Release date	Command
1.0.1	1.0.1.1	Mar 8, 2014	./bin/plugin --install nashorn --url http://bit.ly/1lfjhHd

Do not forget to restart the node after installing.

Project docs

The Maven project site is available at Github

Binaries

Binaries are available at Bintray

Introduction

Let's say you want to use function_score using nashorn. Here is a way of doing it:

curl -XDELETE "http://localhost:9200/test"
curl -XPUT "http://localhost:9200/test/doc/1" -d '{
    "num": 1.0
}'
curl -XPUT "http://localhost:9200/test/doc/2?refresh" -d '{
    "num": 2.0
}'
curl -XGET "http://localhost:9200/test/_search?pretty" -d '
{
  "query": {
    "function_score": {
      "script_score": {
        "script": "doc[\"num\"].value",
        "lang": "nashorn"
     }
   }
  }
}'

It gives:

{
   // ...
   "hits": {
      "total": 2,
      "max_score": 2.0,
      "hits": [
         {
            // ...
            "_score": 2.0
         },
         {
            // ...
            "_score": 1.0
         }
      ]
   }
}

Using Nashorn with script_fields

Let's define script fields:

curl -XDELETE "http://localhost:9200/test"
curl -XPUT "http://localhost:9200/test/doc/1?refresh" -d'
{
  "obj1": {
   "test": "something"
  },
  "obj2": {
    "arr2": [ "arr_value1", "arr_value2" ]
  }
}'
curl -XGET "http://localhost:9200/test/_search?pretty" -d'
{
  "script_fields": {
    "s_obj1": {
      "script": "_source.obj1", "lang": "nashorn"
    },
    "s_obj1_test": {
      "script": "_source.obj1.test", "lang": "nashorn"
    },
    "s_obj2": {
      "script": "_source.obj2", "lang": "nashorn"
    },
    "s_obj2_arr2": {
      "script": "_source.obj2.arr2", "lang": "nashorn"
    }
  }
}'

It gives:

{
  // ...
  "hits": [ {
        // ...
        "fields": {
           "s_obj2_arr2": [ [ "arr_value1", "arr_value2" ] ],
           "s_obj1_test": [ "something" ],
           "s_obj2": [ {
                 "arr2": [ "arr_value1", "arr_value2" ]
           } ],
           "s_obj1": [ {
                 "test": "something"
           } ]
        }
   } ]
}

License

Elasticsearch Nashorn Plugin

Copyright (C) 2014 Jörg Prante

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.