Luceneをベースにした全文検索エンジン。

macOS

brew install elasticsearch

• kuromoji
• kuromoji tokenizer

プラグインとして提供されている

/usr/local/Cellar/elasticsearch/5.6.3/bin/elasticsearch-plugin install analysis-kuromoji

curl -XPOST http://localhost:9200/_analyze --data '{"tokenizer":"kuromoji_tokenizer","text": "オープンソースの全文検索エ ンジン"}' 2>/dev/null | jq .
{
  "tokens": [
    {
      "token": "オープン",
      "start_offset": 0,
      "end_offset": 4,
      "type": "word",
      "position": 0
    },
    {
      "token": "ソース",
      "start_offset": 4,
      "end_offset": 7,
      "type": "word",
      "position": 1
    },
    {
      "token": "の",
      "start_offset": 7,
      "end_offset": 8,
      "type": "word",
      "position": 2
    },
    {
      "token": "全文",
      "start_offset": 8,
      "end_offset": 10,
      "type": "word",
      "position": 3
    },
    {
      "token": "検索",
      "start_offset": 10,
      "end_offset": 12,
      "type": "word",
      "position": 4
    },
    {
      "token": "エンジン",
      "start_offset": 12,
      "end_offset": 16,
      "type": "word",
      "position": 5
    }
  ]
}

辞書なしの場合

curl -XPOST http://localhost:9200/_analyze --data '{"tokenizer":"kuromoji_tokenizer","text": "にゃんにゃんわんわん"}' 2>/dev/null | jq .
{
  "tokens": [
    {
      "token": "に",
      "start_offset": 0,
      "end_offset": 1,
      "type": "word",
      "position": 0
    },
    {
      "token": "ゃんにゃんわんわん",
      "start_offset": 1,
      "end_offset": 10,
      "type": "word",
      "position": 1
    }
  ]
}

辞書ありの場合

text.txtを作成し、/usr/local/etc/elasticsearch/ に設置

にゃん,にゃん,ニャン,名詞
わん,わん,ワン,名詞

curl -XPOST http://localhost:9200/_analyze --data '{"tokenizer":{"type":"kuromoji_tokenizer","user_dictionary": "test.txt"},"text": "にゃんにゃんわんわん"}' 2>/dev/null | jq .
{
  "tokens": [
    {
      "token": "にゃん",
      "start_offset": 0,
      "end_offset": 3,
      "type": "word",
      "position": 0
    },
    {
      "token": "にゃん",
      "start_offset": 3,
      "end_offset": 6,
      "type": "word",
      "position": 1
    },
    {
      "token": "わん",
      "start_offset": 6,
      "end_offset": 8,
      "type": "word",
      "position": 2
    },
    {
      "token": "わん",
      "start_offset": 8,
      "end_offset": 10,
      "type": "word",
      "position": 3
    }
  ]
}