SpringGateWay中处理请求的几个例子

CreateMono.java

// create a Mono that just return an empty list
Mono<List> mono = Mono.create(
    (callback) -> {
      callback.success(Collections.emptyList());
    }
  );

MergeTwoSerivcesResultInGatewayFilterFactory.java

// 访问另外一个服务，获取结果，此例返回值被转为Map类型
Mono<Map> monoA = WebClient.builder()
        .build()
        .get()
        .uri(uriA)
        .header("X-Real-Ip", request.getRemoteAddress().getAddress().toString())
        .retrieve();

Mono<Map> monoB = WebClient.builder()
        .build()
        .get()
        .uri(uriB)
        .header("X-Real-Ip", request.getRemoteAddress().getAddress().toString())
        .retrieve();

//合并2个请求的返回
Mono<Map> mergedResult = Mono.zip(monoA, monoB).map(
     r -> {
       Map m1 = r.getT1();
       Map m2 = r.getT2();
       //处理2个请求的结果，合并
       Map result = new HashMap();
       result.putAll(m1);
       result.putAll(m2);
       return result;
     });

DataBufferFactory dataBufferFactory = exchange.getResponse().bufferFactory();
return exchange
    .getResponse()
    .writeWith(
        mergedResult.map(
            r -> {
              byte[] bin = objectMapper.writeValueAsBytes(r);
              return dataBufferFactory.wrap(bin)
            }
          ));

ModifyRequestInGatewayFilterFacotry.java

  // 修改request
  @Override
  public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
    ServerHttpRequest request = exchange.getRequest();
    ServerHttpRequest newRequest = exchange.getRequest().mutate().header("cus_header", "some value").build();
    return chain.filter(exchange.mutate().request(newRequest).build());
  }

ReturnContentInGatewayFilterFactory.java

  // 在路由中直接返回内容
  public GatewayFilter apply(CashierJournalGatewayFilterFactory.Config config) {
    return (exchange, chain) -> {
      String content = "要返回的内容";
      DataBuffer buffer = exchange.getResponse().bufferFactory().wrap(content.getBytes());
      return exchange.getResponse().writeWith(Flux.just(buffer));
    };
  }