英文:
Method based serialization with Spring Data ElasticSearch 4.x (without Jackson)
问题
我们正在运行一个Java的Spring应用程序，该应用程序使用Spring Data Elasticsearch将数据索引到ElasticSearch中。最近，我的团队从3.x版本升级到了4.x版本。根据https://docs.spring.io/spring-data/elasticsearch/docs/4.0.0.RELEASE/reference/html/#elasticsearch.mapping中的说明，这次升级移除了Jackson映射器。该文档包含以下引用：
使用MappingElasticsearchConverter现在涵盖了所有这些情况。
然而，我还没有找到解决以下问题的方法。我们过去通常通过在模型中拥有对字段进行逻辑处理的方法来构建ElasticSearch中的某些字段。例如：
public class Person {
private String firstName;
private String lastName;
String getFullName(){
return firstName + " " + lastName;
}
}
在3.x版本中，getFullName() 方法会被Jackson默认序列化，从而在ElasticSearch索引中生成一个 'fullName' 字段。但在4.x版本中，这个信息被省略了，我们的索引中不再有 'fullName' 字段。4.x版本中的注解似乎只支持字段的序列化选项，而不支持方法。Jackson的注解（例如@JsonInclude）在这种情况下显然不再起作用。
在使用Spring Data ElasticSearch 4.x版本中，我该如何将方法的结果映射到ElasticSearch中的字段呢？
英文:
We are running a Java, Spring application which indexes to ElasticSearch, using Spring Data Elasticsearch. Recently my team has moved from version 3.x to 4.x. This upgrade removes the Jackson mapper according to https://docs.spring.io/spring-data/elasticsearch/docs/4.0.0.RELEASE/reference/html/#elasticsearch.mapping This document contains the following quote:
> Using the MappingElasticsearchConverter now covers all these cases.
Yet, I have not found a way to resolve the following. We used to build up certain fields in ElasticSearch by having a method in our models that contain logical functions on the fields of this model. For example:
public class Person {
private String firstName;
private String lastName;
String getFullName(){
return firstName + " " + lastName;
}
}
Using version 3.x the getFullName() method would be serialized as default by Jackson, filling our ElasticSearch index with a 'fullName' field. In version 4.x this information is left out from our index. The annotations in 4.x seem to be only supporting serialization options for fields, not methods. Jackson annotations (@JsonInclude for example) obviously do not work here anymore.
How would I be able to map method results to a field in ElasticSearch with Spring Data ElasticSearch 4.x ?
答案1
得分: 1
你可以通过在方法上添加带有PROPERTY参数的@AccessType注解来实现此操作：
import org.springframework.data.annotation.AccessType;
@AccessType(AccessType.Type.PROPERTY)
String getFullName(){
return firstName + " " + lastName;
}
请注意，Spring Data Elasticsearch 还需要一个 setter 方法，因此您需要定义一个空方法：
void setFullName(String ignore){}
如果您对Elasticsearch为此文本属性提供的默认映射满意，那就是全部。
我认为应该可以在没有 setter 的情况下使用这个方法，而且除此之外，您还可以在方法上使用@Field注解，以便为这些属性获得适当的映射。
我创建了一个 Jira 问题 来处理这个。
编辑于 2022 年 10 月 1 日：
此功能已经实现，将在接下来的版本（5.0.RC）中提供。
英文:
You can achieve this by adding the @AccessType annotation with the PROPERTY parameter to the method:
import org.springframework.data.annotation.AccessType;
@AccessType(AccessType.Type.PROPERTY)
String getFullName(){
return firstName + " " + lastName;
}
Please note, that Spring Data Elasticsearch needs a setter as well, so you will need to define an empty method:
void setFullName(String ignore){}
If you are good with the default mappings that Elasticsearch will provide for this text property, that's it.
I think it should be possible to use this without a setter and besides that, it should be possible to put the @Field annotation on the method to be able to have a proper mappings for such properties.
I created a Jira issue for this.
Edit 1.10.2022:
This is implementewd now and will be available in the next version (5.0.RC)
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论