PageJacksonModule doesn't deserialize all Spring Page attributes

[AlexyNau]

Describe the bug
My app is an Spring boot API using these versions :
Spring-cloud-openfeign-core : 3.1.5
Spring-data-commons : 2.7.6

I am using a feign client with an endpoint returning a Page<ClientDTO> like this example :

import org.springframework.data.domain.Page;
/* others imports */

@FeignClient(name = "SpringRemoteApiClient ", url = "${api.spring-remote.url}/users", configuration = FeignConfig.class)
public interface SpringRemoteApiClient {

    @GetMapping(value = "/country/{country}")
    Page<ClientDTO> getClientsByCountry(@PathVariable("country") String country, @ParameterObject @PageableDefault(sort = "name") Pageable pageable);
}

This feign client is a Spring boot OpenAPI application (Spring boot 2.7.6).

If I call directly the endpoint, the JSON reponse will have this structure :

{
  "content": [
    {
      "id": 1,
      "name": "Abc",
      "country": "Def"
    },
  ...
  ],
  "pageable": {
    "page": 0,
    "size": 10,
    "sort": {
      "orders": [
        {
          "direction": "ASC",
          "property": "client.name",
          "ignoreCase": false,
          "nullHandling": "NATIVE",
          "ascending": true,
          "descending": false
        }
      ],
      "empty": false,
      "sorted": true,
      "unsorted": false
    },
    "unpaged": false,
    "paged": true
  },
  "total": 34,
  "last": true,
  "first": false,
  "empty": false
}

And when I call the endpoint with feign, the response is decoded by org.springframework.cloud.openfeign.support.PageJacksonModule

What I get :

Page<ClientDTO> clients = springRemoteApiClient.getClientsByCountry(country, PageRequest.of(0, 10));
clients.getTotalElements(); // 10
clients.getSize(); // 10
clients.getTotalPages(); // 1
clients.getSort().isSorted(); // false
clients.isLast(); // true

What I want :

Page<ClientDTO> clients = springRemoteApiClient.getClientsByCountry(country, PageRequest.of(0, 10));
clients.getTotalElements(); // 34
clients.getSize(); // 10
clients.getTotalPages(); // 4
clients.getSort().isSorted(); // true
clients.isLast(); // false

The response is then incomplete, only content match with SimplePageImpl constructor. Other attributes gets a wrong default value.
The issue is that PageJacksonModule doesn't fullfill number, size, totalElements or sort attributes in SimplePageImpl constructor as you can see here :

/* part of PageJacksonModule */

SimplePageImpl(@JsonProperty("content") List<T> content, @JsonProperty("number") int number, @JsonProperty("size") int size, @JsonProperty("totalElements") @JsonAlias({"total-elements", "total_elements", "totalelements", "TotalElements"}) long totalElements, @JsonProperty("sort") Sort sort) {
            if (size > 0) {
                PageRequest pageRequest;
                if (sort != null) {
                    pageRequest = PageRequest.of(number, size, sort);
                } else {
                    pageRequest = PageRequest.of(number, size);
                }

                this.delegate = new PageImpl(content, pageRequest, totalElements);
            } else {
                this.delegate = new PageImpl(content);
            }

        }

Do you have any solution or is it possible to fix this issue in a future release ?
By adding @JsonProperty("pageable") JsonNode pageable, and @JsonAlias({"total",...}) in the SimplePageImpl constructor for example ?

Thank you,

[OlgaMaciaszek]

Hi @AlexyNau, thanks for reporting this issue. Can you please provide a sample as a link to a small executable app that reproduces the issue instead of separate code snippets? - we'll take a closer look then.

[AlexyNau]

Hello @OlgaMaciaszek, you can find a sample in my repositories.
First, a backend api that is used as a feign client : https://github.com/AlexyNau/my-app
And then, the bff api, where you can reproduce the issue : https://github.com/AlexyNau/bff-my-app
Clone them both and launch them as a SpringBoot Application (JDK 19).
Feel free if you have any questions.

[OlgaMaciaszek]

Thanks for the sample @AlexyNau. I was able to reproduce it. Will provide a fix.

[ffroliva]

Any update on this?

[aliemredeneri]

Any news ?

[OlgaMaciaszek]

Fix merged to main. Will be available with the next 2023.0.x Spring Cloud release.