Getting Different Fields name on swagger while making Restapi in springboot

Question

I am trying to implement AddtoCart functionality for courses.But when I tried to check on my swagger about there is not displaying expected field which i wanted. Can Anyone check my code please.

Swagger Showing these fields:

{
  "additionalProp1": "string",
  "additionalProp2": "string",
  "additionalProp3": "string"
}

CartController

@RestController
public class AddToCartController {

    @Autowired
    CartService cartService;

    @PostMapping("/addToCart")
    public Cart addCartwithCourse(@RequestBody HashMap<String,String> addCartRequest)
    {
        try {
           // String keys[] = {"courseId","userId","qty","price"};

            long courseId = Long.parseLong(addCartRequest.get("courseId"));
            long userId =  Long.parseLong(addCartRequest.get("userId"));
            int qty =  Integer.parseInt(addCartRequest.get("qty"));
            double price = Double.parseDouble(addCartRequest.get("price"));
            Cart obj = cartService.addCartbyUserIdAndCourseId(courseId,userId,qty,price);
            return obj;
        }
        catch (Exception e) {
            e.printStackTrace();
            return null;
        }

    }

}

Cart Model:

package com.hashedin.hu22.entities;

import org.springframework.data.annotation.CreatedDate;

import javax.persistence.*;
import java.time.Instant;

@Entity
public class Cart {

    @Id
    long id;
    int qty;
    double price;
    Long user_id;

    @CreatedDate
    private Instant createdDate;

    String CourseName;


    @OneToOne(cascade = CascadeType.ALL)
    @JoinColumn(name="cr_fid", referencedColumnName = "id")
    Course course;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public int getQty() {
        return qty;
    }

    public void setQty(int qty) {
        this.qty = qty;
    }

    public double getPrice() {
        return price;
    }

    public void setPrice(double price) {
        this.price = price;
    }

    public Long getUser_id() {
        return user_id;
    }

    public void setUser_id(Long user_id) {
        this.user_id = user_id;
    }

    public Instant getCreatedDate() {
        return createdDate;
    }

    public void setCreatedDate(Instant createdDate) {
        this.createdDate = createdDate;
    }

    public String getCourseName() {
        return CourseName;
    }

    public void setCourseName(String courseName) {
        CourseName = courseName;
    }

    public Course getCourse() {
        return course;
    }

    public void setCourse(Course course) {
        this.course = course;
    }

}

AddToCartRepo

public interface AddToCartRepo extends JpaRepository<Cart, Long> {
    @Query("Select addCart  FROM Cart addCart WHERE addCart.course.id= :course_id and addCart.user_id=:user_id")
    Optional<Cart> getCartByProductIdAnduserId(@Param("user_id")Long user_id, @Param("course_id")Long course_id);

    @Query("Select addCart  FROM Cart addCart WHERE addCart.user_id=:user_id")
    List<Cart> getCartByuserId(@Param("user_id")Long user_id);

}

CartService

@Service
public class CartServiceImpl implements CartService {

    @Autowired
    AddToCartRepo addToCartRepo;
    @Autowired
    CourseSerivce courseSerivce;

    @Override
    public Cart addCartbyUserIdAndCourseId(long courseId, long userId, int qty, double price) throws Exception
    {
        try {
                
            if (addToCartRepo.getCartByProductIdAnduserId(userId, courseId).isPresent()) {
                throw new Exception("Product is Already Exist");
            }

            Cart obj = new Cart();
            obj.setQty(qty);
            obj.setUser_id(userId);
            Course course = courseSerivce.getCourseById(courseId);
            obj.setCourse(course);
            obj.setPrice(price);

            return addToCartRepo.save(obj);
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }
        return null;
    }


    @Override
    public List<Cart> getCartByUserId(long userId){
        return addToCartRepo.getCartByuserId(userId);
    }
}

Answer 1

I tried to replicate what you are trying to do and I found many ways to avoid getting this problem! I'm going to post one of the way and hope it helps! In CartController instead of using a hashmap use a DTO(Data Transfer Object) instead with all the fields that are necessary as follows!

CartController

@RestController
public class CartController {

    @Autowired
    CartService cartService;

    @PostMapping("/addToCart")
    public Cart addCartwithCourse(@RequestBody CartDto addCartRequest)
    {
        try {
           // String keys[] = {"courseId","userId","qty","price"};

            long courseId = addCartRequest.getCourseId();
            long userId =  addCartRequest.getUserId();
            int qty =  addCartRequest.getQty();
            double price = addCartRequest.getPrice();
            Cart obj = cartService.addCartbyUserIdAndCourseId(courseId,userId,qty,price);
            return obj;
        }
        catch (Exception e) {
            e.printStackTrace();
            return null;
        }

    }
}

And write a DTO as follows

CartDto

package com.SOF.dto;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class CartDto {
    private long courseId;
    private long userId;
    private int qty;
    private double price;
}

And we will get as follows in swagger

Required body { "courseId": 0, "userId": 0, "qty": 0, "price": 0 }