Question

我试图在调用REST服务之前添加自定义过滤器。在下面的此类中，我试图在HttpRequest中添加自定义过滤器，但出现错误：-

java.lang.UnsupportedOperationException：空在java.util.Collections $ UnmodifiableMap.computeIfAbsent（Collections.java:1535）〜[na：1.8.0_171] 在org.springframework.util.CollectionUtils $ MultiValueMapAdapter.add（CollectionUtils.java:459）〜[spring-core-5.0.7.RELEASE.jar：5.0.7.RELEASE]

public class AuthenticationWebFilter implements WebFilter {
    private static final Logger LOGGER = LoggerFactory.getLogger(AuthenticationWebFilter.class);

    @Autowired
    private TokenServiceRequest tokenServiceRequest;

    @Autowired
    private AuthenticationProvider authenticationProvider;

    public AuthenticationWebFilter(TokenServiceRequest tokenServiceRequest, AuthenticationProvider authenticationProvider) {
        super();
        this.tokenServiceRequest = tokenServiceRequest;
        this.authenticationProvider = authenticationProvider;
    }

    @Override
    public Mono<Void> filter(ServerWebExchange serverWebExchange, WebFilterChain webFilterChain) {
        HttpHeaders requestHeaders = serverWebExchange.getRequest().getHeaders();
        HttpHeaders responseHeaders = serverWebExchange.getResponse().getHeaders();
        LOGGER.info("Response HEADERS: "+responseHeaders);
        LOGGER.info("Request HEADERS: "+serverWebExchange.getRequest().getHeaders());

        tokenServiceRequest.setUsername(serverWebExchange.getRequest().getHeaders().getFirst(CommerceConnectorConstants.USERNAME));
        tokenServiceRequest.setPassword(serverWebExchange.getRequest().getHeaders().getFirst(CommerceConnectorConstants.PASSWORD));
        tokenServiceRequest.setClientId(serverWebExchange.getRequest().getHeaders().getFirst(CommerceConnectorConstants.CLIENT_ID));
        tokenServiceRequest.setSecretClient(serverWebExchange.getRequest().getHeaders().getFirst(CommerceConnectorConstants.SECRET_CLIENT));
        LOGGER.info("Token Received: " + authenticationProvider.getUserAccessToken(tokenServiceRequest).getTokenId());

        //responseHeaders.set(CommerceConnectorConstants.X_AUTH_TOKEN, authenticationProvider.getUserAccessToken(tokenServiceRequest).getTokenId());
        //responseHeaders.add(CommerceConnectorConstants.X_AUTH_TOKEN, authenticationProvider.getUserAccessToken(tokenServiceRequest).getTokenId());

        //This below code is not working
        serverWebExchange.getRequest().getQueryParams().add("test", "value");

        //This below code is not working
        //serverWebExchange.getRequest().getHeaders().add(CommerceConnectorConstants.X_AUTH_TOKEN, authenticationProvider.getUserAccessToken(tokenServiceRequest).getTokenId());
        LOGGER.info("Exiting filter@AuthenticationWebFilter");
        return webFilterChain.filter(serverWebExchange);
    }
    }

在HTTPResponse中，我可以设置自定义标头，但我的要求是在HTTPRequest中添加自定义标头。请告知。

Answer 1

如果您在Spring Cloud Gateway中，则可以通过实现GlobalFilter或GatewayFilter修改请求标头。

    @Component 
    public class LogFilter implements GlobalFilter, Ordered {

    private Logger LOG = LoggerFactory.getLogger(LogFilter.class);

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

        return chain.filter(
                exchange.mutate().request(
                        exchange.getRequest().mutate()
                                .header("customer-header", "customer-header-value")
                                .build())
                        .build());
    }

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

如果您在ZuulFilter中，则addZuulRequestHeader可以修改请求标头。

    RequestContext.getCurrentContext().addZuulRequestHeader("customer-header", "customer-header-value");

希望有帮助。

Answer 2

我认为出于安全原因引发了异常。如果过滤器可以添加/修改HTTP请求标头，那就太麻烦了。当然，您可以通过创建一系列装饰器来实现此目的：

import org.springframework.http.HttpHeaders;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpRequestDecorator;
import org.springframework.util.MultiValueMap;
import org.springframework.web.server.ServerWebExchange;
import org.springframework.web.server.ServerWebExchangeDecorator;
import org.springframework.web.server.WebFilter;
import org.springframework.web.server.WebFilterChain;
import reactor.core.publisher.Mono;

    public class CustomFilter implements WebFilter {

    public Mono<Void> filter(ServerWebExchange serverWebExchange, WebFilterChain webFilterChain) {

            ServerWebExchangeDecorator decorator = new ServerWebExchangeDecoratorImpl(serverWebExchange);

            //do your stuff using decorator 

            return webFilterChain.filter(decorator);
        }
    }


    class ServerWebExchangeDecoratorImpl extends ServerWebExchangeDecorator {

        private ServerHttpRequestDecorator requestDecorator;

        public ServerWebExchangeDecoratorImpl(ServerWebExchange delegate) {
            super(delegate);
            this.requestDecorator = new ServerHttpRequestDecoratorImpl(delegate.getRequest());
        }

        @Override
        public ServerHttpRequest getRequest() {
            return requestDecorator;
        }

    }

    class ServerHttpRequestDecoratorImpl extends  ServerHttpRequestDecorator {

        // your own query params implementation
        private MultiValueMap queryParams;

        public ServerHttpRequestDecoratorImpl(ServerHttpRequest request) {
            super(request);
            this.queryParams = new HttpHeaders();
            this.queryParams.addAll(request.getQueryParams());
        }

        @Override
        public MultiValueMap<String, String> getQueryParams() {
            return queryParams;
        }

        //override other methods if you want to modify the behavior
    }

Answer 3

    public class CustomTokenFilter implements WebFilter {

    @Override
    public Mono<Void> filter(ServerWebExchange serverWebExchange, WebFilterChain webFilterChain) {
        ServerHttpRequest mutateRequest = serverWebExchange.getRequest().mutate()
                .header("token", "test")
                .build();
        ServerWebExchange mutateServerWebExchange = serverWebExchange.mutate().request(mutateRequest).build();
        return webFilterChain.filter(mutateServerWebExchange);
    }
}

Answer 4

我遇到了同样的问题，因为标题已经具有相同的密钥；我的解决办法是在header里面设置key，先检查key是否存在；

@Configuration
public class AuthGatewayFilter implements GlobalFilter, Ordered {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        Consumer<HttpHeaders> httpHeaders = httpHeader -> {
            // check exists
            if(StringUtils.isBlank(httpHeader.getFirst("xxx"))){
                httpHeader.add("xxx", "xxx");
            }
        };
        ServerHttpRequest serverHttpRequest = exchange.getRequest().mutate().headers(httpHeaders).build();
        exchange = exchange.mutate().request(serverHttpRequest).build();

        return chain.filter(exchange);
    }

}

如何在Spring WebFilter中添加自定义标头？

4 个答案: