Installation (POM)

<repository>
    <id>u2ware-mvm-repo</id>
    <url>https://raw.github.com/u2ware/u2ware.github.com/mvn-repo/</url>
</repository>

<dependency>
    <groupId>io.github.u2ware</groupId>
    <artifactId>u2ware-data-rest</artifactId>
    <version>2.3.8.1.RELEASE</version>
</dependency>

Spring Data JPA

Spring Data JPA 는 JPA 를 사용하는 Spring Data Repository 를 제공하며, 자원에 대해 operation 이 가능합니다.

@Entity 
public class Foo{
    @Id @GeneratedValue
    private Long seq;
    private String name;
}

public interface FooRepository extends PagingAndSortingRepository<Foo, Long>{
    Iterable<Foo> findByName(String name);
}

    Foo f = new Foo("a");
    f = fooRepository.save(f); //create
    fooRepository.findById(1); //read
    fooRepository.save(f);     //update
    fooRepository.delete(f);   //delete

    fooRepository.findAll();       //search all
    fooRepository.findByName("b"); //search 

Spring Data REST

Spring Data REST 는 Spring Data Repository 의 리소스를 노출합니다.
예를 들어, FooRepository 를 기반으로 Foo에 대한 REST API 와 Event Handler 를 아래와 같이 제공합니다.

request	before event	operations	after event	response
curl '/foos' -X POST -d '{"name" : ...}'	@HandleBeforeCreate	create	@HandleAfterCreate	json
curl '/foos/1' -X GET		read		json
curl '/foos/1' -X PATCH(or PUT) -d '{"name" : ...}'	@HandleBeforeSave	update	@HandleAfterSave	json
curl '/foos/1' -X DELETE	@HandleBeforeDelete	delete	@HandleAfterDelete	json
curl '/foos/' -X GET		search all		json
curl '/foos/search/findByName?name=hello' -X GET		search		json

@Component
@RepositoryEventHandler
public class FooHandler {
	
	@HandleBeforeCreate
	public void onBeforeCreate(Foo entity) { /* Before [POST] /foos */  }

	@HandleAfterCreate
	public void onAfterCreate(Foo entity) { /* After [POST] /foos */ }
	
	@HandleBeforeSave
	public void onBeforeSave(Foo entity) { /* Before [PATCH or PUT] /foos/1 */	}

	@HandleAfterSave
	public void onAfterSave(Foo entity) { /* Before [PATCH or PUT] /foos/1 */ }
	
	@HandleBeforeDelete
	public void onBeforeDelete(Foo entity) {/* Before [DELETE] /foos/1 */ }

	@HandleAfterDelete
	public void onAfterDelete(Foo entity) { /* Before [DELETE] /foos/1 */}
}

U2ware Data REST

먼저, JPA 를 사용하는 Spring Data Repository 에 QuerydslPredicateExecutor 또는 JpaSpecificationExecutor 확장이 필요합니다.

public interface FooRepository extends PagingAndSortingRepository<Foo, Long>
					,QuerydslPredicateExecutor<Foo> //-- 
					,JpaSpecificationExecutor<Foo>  //--
{  
}

u2ware-data-rest 는 REST API 와 Event Handler 를 추가로 제공합니다.

request	before event	operations	after event	response
curl '/foos/1' -X POST -d '{}'	@HandleAfterRead	read		json
curl '/foos/search' -X POST -d '{"name" : ...}'		search	@HandleBeforeRead	json

@HandleAfterRead

@HandleAfterRead 는 단일 자원에 대한 읽기 이벤트 이며, 이를 통해 확장 포인트를 제공합니다. 다음은 Entity 의 읽기 카운트를 1씩 증가 시키는 예시 입니다.

import io.github.u2ware.data.rest.core.annotation.HandleAfterRead;

@Component
@RepositoryEventHandler
public class ArticleHandler {
	
	private ArticleRepository articleRepository;

	@HandleAfterRead
	public void onAfterRead(Article article) { 
		article.setReadCount(article.getReadCount()+1);
		articleRepository.save(article);
	}	
}

@HandleBeforeRead

(1) Spring Data Repository 가 QuerydslPredicateExecutor 를 확장한 경우, 이벤트 핸들러에 Predicate 객체가 전달됩니다.

public interface HelloRepository extends PagingAndSortingRepository<Hello, Long>
					,QuerydslPredicateExecutor<Hello> //-- (1)
{
}

import io.github.u2ware.data.rest.core.annotation.HandleBeforeRead;

import com.querydsl.core.types.Predicate;

@Component
@RepositoryEventHandler
public class HelloHandler {
	
	@HandleBeforeRead
	public void onBeforeRead(Hello entity, Predicate predicate) { //-- (1)

	}
}

(2) Spring Data Repository 가 JpaSpecificationExecutor 를 확장한 경우, 이벤트 핸들러에 Specification 객체가 전달됩니다.

public interface WorldRepository extends PagingAndSortingRepository<World, Long>
					,JpaSpecificationExecutor<World> //-- (2)
{
}

import io.github.u2ware.data.rest.core.annotation.HandleBeforeRead;

import org.springframework.data.jpa.domain.Specification;

@Component
@RepositoryEventHandler
public class WorldHandler {
	
	@HandleBeforeRead
	public void onBeforeRead(World entity, Specification<World> specification) {  //-- (2)
	
	}
}

QueryDSL Predicate Builder

u2ware-data-rest 는 method chain style 의 QuerydslPredicateBuilder 를 제공합니다.

import io.github.u2ware.data.rest.core.annotation.HandleBeforeRead;
import io.github.u2ware.data.jpa.repository.support.QuerydslPredicateBuilder;

@Component
@RepositoryEventHandler
public class FooHandler {
	
	@HandleBeforeRead
	public void onBeforeRead(Foo entity, Predicate predicate) {

		// method chain style 의  검색 조건 생성 
		QuerydslPredicateBuilder.of(Foo.class)   
			.where()
			.and().eq("name", entity.getName())
			.andStart()
				.andStart()
					.and().eq("age", entity.getAge())
					.or().eq("name", entity.getName())
				.andEnd()
			.andEnd()
		.build(predicate);

	}
}

JPA Specification Builder

u2ware-data-rest 는 method chain style 의 JpaSpecificationBuilder 를 제공합니다.

import io.github.u2ware.data.rest.core.annotation.HandleBeforeRead;
import io.github.u2ware.data.jpa.repository.query.JpaSpecificationBuilder;

@Component
@RepositoryEventHandler
public class FooHandler {
	
	@HandleBeforeRead
	public void onBeforeRead(Foo entity, Specification<Foo> specification) {

		// method chain style 의  검색 조건 생성 
		JpaSpecificationBuilder.of(Foo.class)   
			.where()
			.and().eq("name", entity.getName())
			.andStart()
				.andStart()
					.and().eq("age", entity.getAge())
					.or().eq("name", entity.getName())
				.andEnd()
			.andEnd()
		.build(specification);
	}
}

@Formula with SpEL

u2ware-data-rest 는 Formula Query 안에서 SpEL 을 적용할 수 있도록 지원합니다.

@Component
public class MyStatements {

	public String getStatement(){
		return "a value...";
	}
}

@Entity
public @Data class Bar {

	@Id
	private UUID id;
	private String name;
	private Integer age;

	@Formula("(SELECT count(t.id) FROM foo t WHERE t.name = '#{myStatements.statement}')") //-> SpEL
	@JsonProperty(access=Access.READ_ONLY) 
	private Long count;
}

이를 위해 u2ware-data-rest 에서 제공하는 HibernateAddtionalConfiguration 이 주입되어야 합니다.

import io.github.u2ware.data.jpa.support.HibernateAddtionalConfiguration;

@SpringBootApplication
public class Application {

	public static void main(String[] args) {
		SpringApplication.run(Application.class, args);
	}
	
	@Bean //(1) Formula Query 안에서 SpEL 을 사용하기 위해 필요.
	public HibernateAddtionalConfiguration hibernateAddtionalConfiguration(EntityManagerFactory emf) {
		return new HibernateAddtionalConfiguration(emf);
	}
}

Examples

test 를 통해 더 많은 기능을 확인하십시오.

License

u2ware-data-rest is Open Source software released under the Apache 2.0 license.