如何将自定义查询参数添加到分页hateoas结果中的下一个/上一个链接？

Question

我有以下控制器方法:

@RequestMapping(method = GET, produces = APPLICATION_JSON_VALUE)
@Transactional(readOnly = true)
public ResponseEntity list(Pageable pageable, PagedResourcesAssembler pagedResourcesAssembler) {
    Page<Customer> customers = customerRepository.findAll(pageable);
    return ResponseEntity.ok().body(pagedResourcesAssembler.toResource(customers, customerResourceAssembler));
}

@RequestMapping(value = "/search", method = GET, produces = APPLICATION_JSON_VALUE)
@Transactional(readOnly = true)
public ResponseEntity search(@RequestParam("q") String q, Pageable pageable, PagedResourcesAssembler pagedResourcesAssembler) {
    Specification spec = where(..some specs..);
    Page<Customer> customers = customerRepository.findAll(spec, pageable);
    return ResponseEntity.ok().body(pagedResourcesAssembler.toResource(customers, customerResourceAssembler));
}

第一种方法将所有客户资源作为页面返回.

第二个也返回分页结果,但可以选择提供q要过滤的查询参数.

搜索方法的JSON HATEOAS响应包含下一页链接,如:

{
     "rel": "next",
     "href": "http://localhost:8080/api/customers/search?page=1&size=10{&sort}"
}

问题是这里q查询参数丢失了.

我应该在PagedResourcesAssembler这里使用不同的吗？

Answer 1

我想通过手动创建链接找到了解决方案; 见下面的例子.

@RequestMapping(value = "/search", method = GET, produces = APPLICATION_JSON_VALUE)
@Transactional(readOnly = true)
public ResponseEntity search(@RequestParam("q") String q, Pageable pageable, PagedResourcesAssembler pagedResourcesAssembler) {

    // create link to search method with q; pass link as 3th param to paged resource assembler's toResource method
    Link link = linkTo(methodOn(CustomerController.class).search(q, pageable, pagedResourcesAssembler)).withSelfRel();

    Specification spec = where(..some specs..);
    Page<Customer> customers = customerRepository.findAll(spec, pageable);
    return ResponseEntity.ok().body(pagedResourcesAssembler.toResource(customers, customerResourceAssembler, link));
}