Java – how to use spring data to interact with elastic search aliases

Hi, I'm using elastic search for spring data The domain structure of my project is constantly changing So I have to delete the index to change the mapping every time To solve this problem, I am using aliases

elasticsearchTemplate.createIndex(Test.class);
elasticsearchTemplate.putMapping(Test.class);

    String aliasName = "test-alias";
    AliasQuery aliasQuery = new AliasBuilder()
            .withIndexName("test")
            .withAliasName(aliasName).build();

    elasticsearchTemplate.addAlias(aliasQuery);

I have a test class:

import org.springframework.data.annotation.Id
import org.springframework.data.elasticsearch.annotations.Document
import org.springframework.data.elasticsearch.annotations.Field
import org.springframework.data.elasticsearch.annotations.FieldIndex
import org.springframework.data.elasticsearch.annotations.FieldType
import org.springframework.data.elasticsearch.annotations.Setting


@Document(indexName = "test",type = "test")
@Setting(settingPath = 'elasticSearchSettings/analyzer.json')
class Test  extends BaseEntity{

@Id
@Field(type = FieldType.String,index = FieldIndex.not_analyzed)
String id

@Field(type = FieldType.String,index = FieldIndex.analyzed,indexAnalyzer = "generic_analyzer",searchAnalyzer = "generic_analyzer")
String firstName



}

Testrepository class:

package com.as.core.repositories

import com.as.core.entities.Test
import org.springframework.data.elasticsearch.repository.ElasticsearchRepository

interface TestRepository extends ElasticsearchRepository<Test,String>          
{


}

My question is how to read from the alias instead of the index itself? Whether the write operation also occurs on the alias I checked the following links: https://www.elastic.co/guide/en/elasticsearch/guide/current/index-aliases.html#index -Aliases it says that we will have to exchange aliases instead of actual indexes How to use elasticsearch spring data Java API to achieve this

Solution

I solved this limitation by using elasticsearchtemplate in the repository class associated with the object (although it would be better if there was a way to specify an alias on the entity itself)

It works by creating custom repository interfaces In your case, it will be testrepository custom:

public interface TestRepositoryCustom
{
    Test> findByCustom(...);
}

Then implement this interface, appending "impl" to the end of the base repository Name:

public class TestRepositoryImpl implements TestRepositoryCustom
{
    Page<Test> findByCustom(Pageable pageable,...)
    {
        BoolQueryBuilder boolQuery = new BoolQueryBuilder();
        FilterBuilder filter = FilterBuilders.staticMethodsToBuildFilters;
        /*
         * Your code here to setup your query
        */

        NativeSearchQueryBuilder builder = new NativeSearchQueryBuilder().withQuery(boolQuery).withFilter(filter).withPageable(pageable); 

        //These two are the crucial elements that will allow the search to look up based on alias
        builder.withIndices("test-alias");
        builder.withTypes("test");

        //Execute the query
        SearchQuery searchQuery = builder.build();
        return elasticSearchTemplate.queryForPage(searchQuery,Test.class);
    }
}

Finally, in your base JPA repository interface testrepository, extend the testrepository custom interface to access any method on the custom interface from your repository bean

public interface TestRepository extends ElasticsearchRepository<Consultant,String>,TestRepositoryCustom
{
}

What I really want to see is comments on entities, such as:

@Document(aliasName="test-alias")

This will work in the background to provide the ability to search this index from the door so that all JPA queries work correctly, regardless of the index name