如何基于HTTP方法进行Zuul动态路由,并通过'serviceId'解析目标主机？

Question

如何基于HTTP方法(GET/POST/PUT ...)进行Zuul动态路由？例如,当您需要将POST请求路由到不同的主机而不是' zuul.routes.* '中描述的默认主机时 ...

zuul:
  routes:
    first-service:
      path: /first/**
      serviceId: first-service
      stripPrefix: false

    second-service:
      path: /second/**
      serviceId: second-service
      stripPrefix: false

即当我们请求' GET/first '时,Zuul将请求路由到' first-service ',但如果我们请求' POST/first ',则Zuul将请求路由到' second-service '.

Answer 1

要实现基于HTTP方法的动态路由,我们可以创建自定义" 路由 "类型ZuulFilter并通过解析'serviceId' DiscoveryClient.例如:

@Component
public class PostFilter extends ZuulFilter {

    private static final String REQUEST_PATH = "/first";
    private static final String TARGET_SERVICE = "second-service";
    private static final String HTTP_METHOD = "POST";

    private final DiscoveryClient discoveryClient;

    public PostOrdersFilter(DiscoveryClient discoveryClient) {
        this.discoveryClient = discoveryClient;
    }

    @Override
    public String filterType() {
        return "route";
    }

    @Override
    public int filterOrder() {
        return 0;
    }

    @Override
    public boolean shouldFilter() {
        RequestContext context = RequestContext.getCurrentContext();
        HttpServletRequest request = context.getRequest();
        String method = request.getMethod();
        String requestURI = request.getRequestURI();
        return HTTP_METHOD.equalsIgnoreCase(method) && requestURI.startsWith(REQUEST_PATH);
    }

    @Override
    public Object run() {

        RequestContext context = RequestContext.getCurrentContext();
        List<ServiceInstance> instances = discoveryClient.getInstances(TARGET_SERVICE);
        try {
            if (instances != null && instances.size() > 0) {
                context.setRouteHost(instances.get(0).getUri().toURL());
            } else {
                throw new IllegalStateException("Target service instance not found!");
            }
        } catch (Exception e) {
            throw new IllegalArgumentException("Couldn't get service URL!", e);
        }
        return null;
    }
}