Projections.constructor cannot be nested when using r2dbc-querydsl associated queries

zhoachenIt commented 1 year ago

r2dbc can't map nested class data when doing associative queries, but it can in jpa mode. Here's my code

<dependency>
    <groupId>io.asyncer</groupId>
    <artifactId>r2dbc-mysql</artifactId>
    <version>0.9.3</version>
</dependency>

<dependency>
    <groupId>com.mysql</groupId>
    <artifactId>mysql-connector-j</artifactId>
    <scope>runtime</scope>
</dependency>

<dependency>
    <groupId>com.infobip</groupId>
    <artifactId>infobip-spring-data-r2dbc-querydsl-boot-starter</artifactId>
    <version>7.2.4</version>
</dependency>

pojo

@Getter
@Setter
public class SysUserDTO {

    private Long id;

    private String username;

    private String name;

    private Long deptId;

    private SysDeptDTO sysDeptDTO;

    public SysUserDTO(Long id, String username, String name, Long deptId) {
        this.id = id;
        this.username = username;
        this.name = name;
        this.deptId = deptId;
    }

    public SysUserDTO(Long id, String username, String name, Long deptId, SysDeptDTO sysDeptDTO) {
        this.id = id;
        this.username = username;
        this.name = name;
        this.deptId = deptId;
        this.sysDeptDTO = sysDeptDTO;
    }

    public SysUserDTO() {
    }
}

@Getter
@Setter
public class SysDeptDTO {

    private String deptName;

    public SysDeptDTO(String deptName) {
        this.deptName = deptName;
    }

    public SysDeptDTO() {
    }

}

repository

public interface UserRepository extends QuerydslR2dbcRepository<SysUser, Long> {

    Mono<SysUser> findByUsername(String username);

}

service

import com.example.webflux.model.SysDeptDTO;
import com.example.webflux.model.SysUser;
import com.example.webflux.model.SysUserDTO;
import com.example.webflux.repository.UserRepository;
import com.querydsl.core.types.Projections;
import lombok.RequiredArgsConstructor;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;
import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

import static com.example.webflux.model.QSysDept.sysDept;
import static com.example.webflux.model.QSysUser.sysUser;

@Service
@RequiredArgsConstructor
public class UserService {

    private final UserRepository userRepository;

    @Transactional(readOnly = true)
    public Flux<SysUserDTO> findByName(String name) {
        return userRepository.query(query -> query
                .select(
                        Projections.constructor(SysUserDTO.class,
                                sysUser.id,
                                sysUser.name,
                                sysUser.username,
                                sysUser.deptId.as("deptId"),
                                Projections.constructor(SysDeptDTO.class, sysDept.name)
                        )
                )
                .from(sysUser)
                .innerJoin(sysDept)
                .on(sysUser.deptId.eq(sysDept.id))
                .where(sysUser.name.like("%" + name + "%"))
        ).all();
    }

}

controller

@RestController
@RequestMapping("/users")
@RequiredArgsConstructor
public class WebFluxController {

    private final UserService userService;

    @GetMapping("/name/{name}")
    public Flux<SysUserDTO> getName(@PathVariable String name) {
        return this.userService.findByName(name);
    }

}

Request response result, sysDeptDTO is null

[{"id":1,"username":"admin","name":"zhangsan","deptId":1,"sysDeptDTO":null}]

I wrote the same code using jpa mode, but sysDeptDTO successfully assigns the value

[{"id":1,"username":"admin","name":"zhangsan","deptId":1,"sysDeptDTO":{"deptName":"it"}}]