Spring webflux：如何配置Controller和WebClient像代理一样工作？

Question

我需要一个可以在代理模式下工作的端点：将请求转发到外部 REST API。目前我实现了这样的 class 但它离理想还很远。

import java.net.URI;
import org.springframework.http.HttpMethod;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.reactive.function.BodyInserters;
import org.springframework.web.reactive.function.client.WebClient;
import org.springframework.web.util.UriComponentsBuilder;
import reactor.core.publisher.Mono;

@RestController
public class ProxyController2 {

  private static final int OFFSET = 4;
  private static final String SCHEME = "http";
  private static final String HOTS = "127.0.0.1";
  private static final String PORT = "9090";

  @RequestMapping("/proxy/public/**")
  public Mono<String> publicProxy(ServerHttpRequest request) {
    HttpMethod httpMethod = request.getMethod();

    if (bodyRequired(httpMethod)) {
      return WebClient.create()
          .method(httpMethod)
          .uri(composeTargetUri(request))
          .headers(headers -> headers.addAll(request.getHeaders()))
          .body(BodyInserters.fromDataBuffers(request.getBody()))
          .retrieve()
          .bodyToMono(String.class);
    } else {
      return WebClient.create()
          .method(httpMethod)
          .uri(composeTargetUri(request))
          .headers(headers -> headers.addAll(request.getHeaders()))
          .retrieve()
          .bodyToMono(String.class);
    }
  }

  private URI composeTargetUri(ServerHttpRequest request) {
    return UriComponentsBuilder.newInstance()
        .scheme(SCHEME)
        .host(HOTS)
        .port(PORT)
        .path(getTargetPath(request))
        .build()
        .toUri();
  }

  private String getTargetPath(ServerHttpRequest request) {
    return request.getPath().pathWithinApplication()
        .subPath(OFFSET)
        .value();
  }

  private boolean bodyRequired(HttpMethod httpMethod) {
    return httpMethod == HttpMethod.DELETE || httpMethod == HttpMethod.POST
        || httpMethod == HttpMethod.PUT;
  }
}

它有一些缺点：
* 它总是 returns 结果为字符串。
* 我们失去回应 headers.
* 我们失去响应状态（它产生 500 错误消息描述）。

你知道在spring webflux 应用程序中创建代理控制器的好方法吗？

Answer 1

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Spring webflux：如何配置Controller和WebClient像代理一样工作？

Spring webflux: how to configure Controller and WebClient to work like proxy?

java

spring

spring-boot

spring-webflux