elasticsearch-script-plugin

This project is a super simple example of an Elasticsearch script plugin.

See: https://www.elastic.co/guide/en/elasticsearch/reference/6.6/modules-scripting-engine.html

Runs on Elasticsearch 6.6.0 and Java 1.8.

Quick Start

Gradle and Java info.

elasticsearch-script-plugin $ gradle -v

------------------------------------------------------------
Gradle 5.2.1
------------------------------------------------------------

Build time:   2019-02-08 19:00:10 UTC
Revision:     f02764e074c32ee8851a4e1877dd1fea8ffb7183

Kotlin DSL:   1.1.3
Kotlin:       1.3.20
Groovy:       2.5.4
Ant:          Apache Ant(TM) version 1.9.13 compiled on July 10 2018
JVM:          1.8.0_202 (Oracle Corporation 25.202-b08)
OS:           Mac OS X 10.14.3 x86_64

Build Docker Container

The following will build the plugin and build a docker container with the plugin installed.

gradle docker

Run Docker Image

The following will spin up a two node ES cluster in docker.

docker-compose -f misc/docker-compose.yml up

To shut down run

docker-compose -f misc/docker-compose.yml down

Create Some Documents

The following curl commands will create two documents that have the term 'foo' in the 'body' field.

curl -X PUT "localhost:9200/some/doc/1" -H 'Content-Type: application/json' -d'
{
    "body" : "foo bar zoo baz moo foo foo foo"
}'
curl -X PUT "localhost:9200/some/doc/2" -H 'Content-Type: application/json' -d'
{
    "body" : "foo bar baz"
}'

Run Search and Trigger Script Plugin

The following search will trigger our custom script plugin because it's looking for documents that have 'foo' in the 'body' field. The more 'foo' you have in your 'body' the higher your _score.

You can change / add / remove params passed to the script below to prove that the script is actually being called and does different things based on different params. If you remove either params, the script will throw an error.

curl -X POST "localhost:9200/_search" -H 'Content-Type: application/json' -d'
{
  "query": {
    "function_score": {
      "query": {
        "match": {
          "body": "foo"
        }
      },
      "functions": [
        {
          "script_score": {
            "script": {
                "source": "pure_df",
                "lang" : "expert_scripts",
                "params": {
                    "field": "body",
                    "term": "foo"
                }
            }
          }
        }
      ]
    }
  }
}'

Here's the output from the above search. You can see that the score is higher for doc 1 than for doc 2.

{
    "took": 256,
    "timed_out": false,
    "_shards": {
        "total": 5,
        "successful": 5,
        "skipped": 0,
        "failed": 0
    },
    "hits": {
        "total": 2,
        "max_score": 1.9473865,
        "hits": [
            {
                "_index": "some",
                "_type": "doc",
                "_id": "1",
                "_score": 1.9473865,
                "_source": {
                    "body": "foo bar zoo baz moo foo foo foo",
                    "post_date": "2009-11-15T14:12:12",
                    "message": "trying out Elasticsearch"
                }
            },
            {
                "_index": "some",
                "_type": "doc",
                "_id": "2",
                "_score": 0.2876821,
                "_source": {
                    "body": "foo bar zoo"
                }
            }
        ]
    }
}