Elasticsearch：获取用于从客户端索引给定字段的分析器

Question

有没有办法通过客户端以编程方式获取 Elasticsearch 服务器实例用于索引给定字段的 analyzer（当然，假设分析器在双方都可用）？

例如，使用如下映射：

{
    "mappings": {
        "article": {
            "properties": {
                "text": {
                    "type": "string",
                    "index": "analyzed",
                    "analyzer": "spanish"
                }
            }
        }
    }
}

如何使用the Java client for Elasticsearch 为字段text 获取org.apache.lucene.analysis.es.SpanishAnalyzer，如下所示？

import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.Collections;

import org.elasticsearch.action.search.SearchRequestBuilder;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.Client;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.transport.InetSocketTransportAddress;
import org.elasticsearch.index.query.QueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;

public class QueryAnalyzerTest {

    public static void main(final String[] args) throws UnknownHostException {
        final String docTextFieldName = "text";
        Iterable<SearchHit> hits = Collections.emptyList();

        try (final Client client = TransportClient.builder().build()
                .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("localhost"), 9300))) {
            final QueryBuilder queryBuilder = QueryBuilders.matchQuery(docTextFieldName, "anuncio");
            final SearchRequestBuilder searchRequestBuilder = client.prepareSearch("news").setQuery(queryBuilder)
                    .setTypes("article");
            final SearchResponse response = searchRequestBuilder.get();
            hits = response.getHits();
        }

        hits.forEach(hit -> {
            final String docText = (String) hit.getSource().get(docTextFieldName);
            // TODO: Tokenize "docText" with the exact same tokenizer used when
            // indexing the field
        });

    }

}

Answer 1

您绝对可以使用client().admin().indices().prepareGetFieldMappings("indexName") 以编程方式获取text 字段的映射，并且您将能够检索分析器的逻辑名称（即“西班牙语”），但是，您不会得到分析器的类名。

为此，您需要调用AnalysisRegistry.getAnalyzer("spanish")，您将获得正确的分析器实例。