JavaScript lang Plugin for Elasticsearch

The JavaScript language plugin allows to have javascript (or js) as the language of scripts to execute.

In order to install the plugin, simply run:

bin/plugin -install elasticsearch/elasticsearch-lang-javascript/2.3.0

You need to install a version matching your Elasticsearch version:

elasticsearch	JavaScript Plugin	Docs
master	Build from source	See below
es-1.x	Build from source	2.4.0-SNAPSHOT
es-1.3	2.3.0	2.3.0
es-1.2	2.2.0	2.2.0
es-1.1	2.1.0	2.1.0
es-1.0	2.0.0	2.0.0
es-0.90	1.4.0	1.4.0

To build a SNAPSHOT version, you need to build it with Maven:

mvn clean install
plugin --install lang-javascript \
       --url file:target/releases/elasticsearch-lang-javascript-X.X.X-SNAPSHOT.zip

Using javascript with function_score

Let's say you want to use function_score API using javascript. 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": "javascript"
      }
    }
  }
}'

gives

{
   // ...
   "hits": {
      "total": 2,
      "max_score": 4,
      "hits": [
         {
            // ...
            "_score": 4
         },
         {
            // ...
            "_score": 1
         }
      ]
   }
}

Using javascript with 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" -d'
{
  "script_fields": {
    "s_obj1": {
      "script": "_source.obj1", "lang": "js"
    },
    "s_obj1_test": {
      "script": "_source.obj1.test", "lang": "js"
    },
    "s_obj2": {
      "script": "_source.obj2", "lang": "js"
    },
    "s_obj2_arr2": {
      "script": "_source.obj2.arr2", "lang": "js"
    }
  }
}'

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

This software is licensed under the Apache 2 license, quoted below.

Copyright 2009-2014 Elasticsearch <http://www.elasticsearch.org>

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.