Korean Analysis for ElasticSearch 6.1.1

The Korean Analysis plugin integrates the Lucene Korean analysis module into the Text Search Engine(Server) ElasticSearch.

The Analysis Plugin version must be exactly the same as the version of ElasticSearch you are running.

Check elasticsearch version you are running:

$ curl -XGET 'http://localhost:9200'

Install plugin

In order to install the plugin, git clone and copy:

$ git clone https://github.com/usemodj/elasticsearch-analysis-korean.git
$ cd elasticsearch-analysis-korean/
$ sudo cp -R dist/analysis-korean /usr/share/elasticsearch/plugins/

And restart elasticsearch service:

$ sudo service elasticsearch restart
...
$ sudo service elasticsearch status

For checking the elasticsearch log:

$ sudo tail -f /var/log/elasticsearch/elasticsearch.log

Check elasticsearch version:

$ curl -XGET 'http://localhost:9200'

# print the elasticsearch version
{
  "name" : "DGJeJk2",
  "cluster_name" : "elasticsearch",
  "cluster_uuid" : "p-XSaQChSPymZ6QCzb1D_g",
  "version" : {
    "number" : "6.1.1",
    "build_hash" : "bd92e7f",
    "build_date" : "2017-12-17T20:23:25.338Z",
    "build_snapshot" : false,
    "lucene_version" : "7.1.0",
    "minimum_wire_compatibility_version" : "5.6.0",
    "minimum_index_compatibility_version" : "5.0.0"
  },
  "tagline" : "You Know, for Search"
}

Test ElasticSeach Korean Analysis Plugin

# Delete `test` index:
$ curl -XDELETE http://localhost:9200/test

# Create `test` index for `kr_analyzer` korean-analysis analyzer:
$ curl -XPUT 'http://localhost:9200/test' -H 'Content-Type: application/json' -d '{
  "settings": {
      "analysis": {
        "analyzer": {
          "kr_analyzer": {
            "type": "custom",
            "tokenizer": "kr_tokenizer",
            "filter": [ "trim", "kr_filter" ]
          }
        }
      }
  }
}'

Results: {"acknowledged":true,"shards_acknowledged":true,"index":"test"}

# Analyze `test` index for `kr_analyzer` korean-analysis analyzer:

$ curl -XGET 'localhost:9200/_analyze?pretty' -H 'Content-Type: application/json' -d '{
  "analyzer": "kr_analyzer",
  "text": "아버지가 가방에 들어가셨다."
}'

Result:

{
  "tokens" : [
    {
      "token" : "아버지가",
      "start_offset" : 0,
      "end_offset" : 4,
      "type" : "word",
      "position" : 0
    },
    {
      "token" : "아버지",
      "start_offset" : 0,
      "end_offset" : 3,
      "type" : "word",
      "position" : 0
    },
    {
      "token" : "가방에",
      "start_offset" : 5,
      "end_offset" : 8,
      "type" : "word",
      "position" : 1
    },
    {
      "token" : "가방",
      "start_offset" : 5,
      "end_offset" : 7,
      "type" : "word",
      "position" : 1
    },
    {
      "token" : "들어가셨다",
      "start_offset" : 9,
      "end_offset" : 14,
      "type" : "word",
      "position" : 2
    }
  ]
}

The plugin includes the kr_analyzer analyzer, kr_tokenizer tokenizer, and kr_filter token filter.

---

Build source code

1. Installing Apache Maven:

• Ensure JAVA_HOME environment variable is set and points to your JDK installation
• Extract distribution archive in /opt/ directory
• Add the bin directory of the created directory apache-maven-3.5.2 to the PATH environment variable

$ echo $JAVA_HOME
/usr/lib/jvm/java-9-oracle

$ wget http://mirror.apache-kr.org/maven/maven-3/3.5.2/binaries/apache-maven-3.5.2-bin.tar.gz
$ tar xzvf apache-maven-3.5.2-bin.tar.gz
$ sudo mv apache-maven-3.5.2 /opt/
 
$ echo 'export PATH="/opt/apache-maven-3.5.2/bin:$PATH"' >> ~/.bashrc
$ source ~/.bashrc

# Check maven:
$ mvn -v

Maven home: /opt/apache-maven-3.5.2
Java version: 9.0.1, vendor: Oracle Corporation
Java home: /usr/lib/jvm/java-9-oracle
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "4.10.0-42-generic", arch: "amd64", family: "unix"

2. Building analysis-korean 6.1.1 :

$ mvn verify