Question

我一直按照指南使用Spring HATEOAS：

https://spring.io/guides/gs/rest-hateoas/#initial

package hello;

import static org.springframework.hateoas.mvc.ControllerLinkBuilder.*;

import org.springframework.http.HttpEntity;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

@RestController
public class GreetingController {

    private static final String TEMPLATE = "Hello, %s!";

    @RequestMapping("/greeting")
    public HttpEntity<Greeting> greeting(@RequestParam(value = "name", required = false, defaultValue = "World") String name) {

        Greeting greeting = new Greeting(String.format(TEMPLATE, name));
        greeting.add(linkTo(methodOn(GreetingController.class).greeting(name)).withSelfRel());

        return new ResponseEntity<Greeting>(greeting, HttpStatus.OK);
    }
}

现在我想使用存储库并输出Flux / Mono响应：

@RestController
class PersonController {

    private final PersonRepository people;

    public PersonController(PersonRepository people) {
        this.people = people;
    }

    @GetMapping("/people")
    Flux<String> namesByLastname(@RequestParam Mono<String> lastname) {

        Flux<Person> result = repository.findByLastname(lastname);
        return result.map(it -> it.getFullName());
    }
}

如何在Flux / Mono响应中使用Spring HATEOAS？它有可能吗？

Answer 1

我认为这个项目不支持（还有？）Spring Framework中的新反应支持。你最好的选择是reach out to the maintainers and contribute to the project（创建一个问题并解释你想要实现的目标是一个开始！）。

Answer 2

更新，因为支持将HATEOAS与Spring Web Flux一起使用。

public class Person extends ResourceSupport
{
    public Person(Long uid, String name, String age) {
        this.uid = uid;
        this.name = name;
        this.age = age;
    }

    private Long uid;
    private String name;
    private String age;

    public Long getUid() {
        return uid;
    }

    public void setUid(Long uid) {
        this.uid = uid;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getAge() {
        return age;
    }

    public void setAge(String age) {
        this.age = age;
    }
}

按以下方式在Controller中使用上述人员

@GetMapping("/all")
    public Flux getAllPerson() {
        Flux<List<Person>> data = Flux.just(persons);
        return data.map(x ->  mapPersonsRes(x));
    }

    private List<Resource<Person>> mapPersonsRes(List<Person> persons) {
    List<Resource<Person>> resources = persons.stream()
            .map(x -> new Resource<>(x,
                    linkTo(methodOn(PersonController.class).getPerson(x.getUid())).withSelfRel(),
                    linkTo(methodOn(PersonController.class).getAllPerson()).withRel("person")))
            .collect(Collectors.toList());
    return resources;
}

或者，如果您想要一个人，也可以使用Mono

@GetMapping("/{id}")
public Mono<Resource<Person>> getPerson(@PathVariable("id") Long id){
    Mono<Person> data = Mono.justOrEmpty(persons.stream().filter(x -> x.getUid().equals(id)).findFirst());
    Mono person = data.map(x -> {
        x.add(linkTo(methodOn(PersonController.class).getPerson(id)).withSelfRel());
        return x;
    });
    return person;
}

这是Flux / Mono提供的.map功能的简单使用。我希望这对以后的观众有用。

关于Spring Flux / Mono响应的HATEOAS

2 个答案: