mridang / elastijack

Elastijack

Elastijack (aptly named) is a Jackson-based module for working with Elasticsearch documents. At the time of writing, Elastijac can only be used for mapping generation using Jackson, and also provides a mapper with the correct defaults to serde Elasticsearch documents.

Installation

Unfortunately, Elastijack is not available in any public Maven repositories except the GitHub Package Registry. For more information on how to install packages from the GitHub Package Registry, https://docs.github.com/en/packages/guides/configuring-gradle-for-use-with-github-packages#installing-a-package

Usage

As the Elastisearch clients provide no support for mapping generation, this module is supposed to be a drop-in module to augment existing functionality provided by the existing Datastax libraries.

Assume you have the following bean for which you would like to generate the mapping:

import java.util.Date;

import com.datastax.oss.driver.api.mapper.annotations.CqlName;
import com.datastax.oss.driver.api.mapper.annotations.Entity;
import com.datastax.oss.driver.api.mapper.annotations.PartitionKey;
import com.nosto.elastijack.annotations.OrderedClusteringColumn;
import com.nosto.elastijack.types.FrozenList;

@Entity(defaultKeyspace = "mykeyspace")
@CqlName("brandsimilarities")
public class BrandSimilarities {

    @SuppressWarnings("DefaultAnnotationParam")
    @PartitionKey(0)
    @CqlName("brand")
    public String brand;

    @SuppressWarnings("DefaultAnnotationParam")
    @OrderedClusteringColumn(isAscending = false, value = 0)
    @CqlName("createdat")
    public Date createdAt;

    @OrderedClusteringColumn(isAscending = true, value = 1)
    @CqlName("skuid")
    public String skuId;

    @CqlName("related")
    public FrozenList<Relation> productRelations;

    @CqlName("relation")
    public static class Relation {

        @CqlName("brand")
        public String brand;

        @CqlName("skuid")
        public String skuId;

        @CqlName("score")
        public Float score;
    }
}

To generate the schema for the bean described above, you would run:

    val mapper = new CassandraJavaBeanMapper[BrandSimilarities]()
    val createSchema: String = mapper.generateMappingProperties

to yield the DDL:

CREATE 
  TYPE 
IF NOT 
EXISTS relation 
     ( score FLOAT
     , skuid TEXT
     , brand TEXT
     );

CREATE 
 TABLE 
IF NOT 
EXISTS brandsimilarities 
     ( brand TEXT
     , shardkey TINTINT
     , createdat TEXT
     , skuid TEXT
     , related LIST<FROZEN<relation>>
     , PRIMARY KEY
       ( ( brand
         , shardkey
          )
       , createdat
       , skuid
       )
    )
  WITH CLUSTERING 
 ORDER 
    BY 
     ( createdat DESC
     , skuid ASC
     );

License

Apache License

Copyright (c) 2021 Nosto Oy.