spring - 如何在 Spring WebFilter 中添加自定义 header ？

Question

我尝试在调用 REST 服务之前添加自定义过滤器。在下面的类中，我尝试在 HttpRequest 中添加自定义过滤器，但出现错误:-

java.lang.UnsupportedOperationException:null 在 java.util.Collections$UnmodifyingMap.computeIfAbsent(Collections.java:1535) ~[na:1.8.0_171] 在 org.springframework.util.CollectionUtils$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 header ，但我的要求是在 HTTPRequest 中添加自定义 header 。请指教。

Answer 1

如果您使用的是 Spring Cloud Gateway，则可以通过实现 GlobalFilter 或 GatewayFilter 来修改请求 header 。

    @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，addZuulRequestHeader 可以修改请求 header 。

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

希望对您有帮助。