Mapping all request params into an object in Spring Controller

Question

So, url requested looks like

localhost:8080/contacts?id=22&name=John&eventId=11

and also I got an object to map request into

public class ContactDTO {
    private Long id;
    private String name;
    private Long eventId;
}

I use a controller method like passing my request params into an object

@GetMapping("/contacts")
public ContactDTO contacts(ContactDTO contact) {
    // everything is awesome! contact maps clearly
    return contact;
}

The question is how to map like this but have different name

    localhost:8080/contacts?id=22&name=John&event_id=11

Setting @JsonAttribute doesn't works because Jackson mapper works only in requestbody. Maybe I should write custom HandlerMethodArgumentResolver or something like that?

P.S. I've got a dirty hack (objectMapper is injected, so I can use @JsonAttributes), But this case fails on array mapping, same mapping with requestbody works fine

@GetMapping("/contacts")
public ContactsDTO contacts(@RequestParam Map<String,String> params) {
    ContactDTO contactDTO = objectMapper.convertValue(params,ContactDTO.class);
    return contactDTO;
}

change mapping to `Post` and create a `QueryDto (for example)` and use it the way you want. IMHO using json is way better and will save your life. — bananas, Nov 19 '19 at 10:57
@emotionlessbananas I know how to do this in POST easily, but now I must do it in GET — Ivan, Nov 19 '19 at 12:12

alexmagnus · Accepted Answer · 2019-11-19T12:42:45.317

Since it is an API design requirement, it should be clearly reflected in the corresponding DTO's and endpoints.

Usually, this kind of requirement stems from a parallel change and implies that the old type queries will be disabled during the contract phase.

You could approach the requirement by adding the required mapping "query-parameter-name-to-property-name" by adding it to the ContactDTO. The simplest way would be just to add an additional setter like below

public class ContactDTO {
    private Long id;
    private String name;
    private Long eventId;

    public void setEvent_id(Long eventId) {
        this.eventId = eventId;
    }
}

If you prefer immutable DTO's, then providing a proper constructor should work as well

@Value
public class ContactDTO {
    private Long id;
    private String name;
    private Long eventId;

    public ContactDTO(Long id, String name, String eventId, String event_id) {
        this.id = id;
        this.name = name;
        this.eventId = eventId != null ? eventId : event_id;
    }
}

score -1 · Answer 2 · answered Nov 19 '19 at 11:14

-1

Use something like

@RequestParam(name="event_id", required = true) long eventId

in the parameter list to change the parameter name.

answered Nov 19 '19 at 11:14

kopaka

535
4
17

I know how to change parameter name in the list of params, but I got no list of params! My method consumes automatically mapped DTO, check the question again, please – Ivan Nov 19 '19 at 12:06

score -6 · Answer 3 · answered Nov 19 '19 at 10:52

-6

Use @RequestBody insteaf of @requestparam.

answered Nov 19 '19 at 10:52

arun

26
5

1

It is GET method, and all request prams send in query url – Ivan Nov 19 '19 at 10:55

Mapping all request params into an object in Spring Controller

3 Answers3