Java 如何向假客户端添加请求拦截器？

How to add a request interceptor to a feign client?

提问by Gustavo

I want every time when I make a request through feign client, to set a specific header with my authenticated user.

我希望每次通过 feign 客户端发出请求时，都为我的经过身份验证的用户设置一个特定的标头。

This is my filter from which I get the authentication and set it to the spring security context:

这是我从中获取身份验证并将其设置为 spring 安全上下文的过滤器：

@EnableEurekaClient
@SpringBootApplication
@EnableFeignClients
public class PerformanceApplication {
    @Bean
    public Filter requestDetailsFilter() {
        return new RequestDetailsFilter();
    }

    public static void main(String[] args) {
        SpringApplication.run(PerformanceApplication.class, args);
    }

    private class RequestDetailsFilter implements Filter {
        @Override
        public void init(FilterConfig filterConfig) throws ServletException {

        }

        @Override
        public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
            String userName = ((HttpServletRequest)servletRequest).getHeader("Z-User-Details");
            String pass = ((HttpServletRequest)servletRequest).getHeader("X-User-Details");
            if (pass != null)
                pass = decrypt(pass);
            SecurityContext secure = new SecurityContextImpl();
            org.springframework.security.core.Authentication token = new UsernamePasswordAuthenticationToken(userName, pass);
            secure. setAuthentication(token);
            SecurityContextHolder.setContext(secure);
            filterChain.doFilter(servletRequest, servletResponse);
        }

        @Override
        public void destroy() {

        }
    }
    private String decrypt(String str) {
        try {
            Cipher dcipher = new NullCipher();

            // Decode base64 to get bytes
            byte[] dec = new sun.misc.BASE64Decoder().decodeBuffer(str);

            // Decrypt
            byte[] utf8 = dcipher.doFinal(dec);

            // Decode using utf-8
            return new String(utf8, "UTF8");
        } catch (javax.crypto.BadPaddingException e) {
        } catch (IllegalBlockSizeException e) {
        } catch (UnsupportedEncodingException e) {
        } catch (java.io.IOException e) {
        }
        return null;
    }
}

This is my feign client:

这是我的假客户：

@FeignClient("holiday-client")
public interface EmailClient {
    @RequestMapping(value = "/api/email/send", method = RequestMethod.POST)
    void sendEmail(@RequestBody Email email);
}

And here I have a request interceptor:

在这里我有一个请求拦截器：

@Component
public class FeignRequestInterceptor implements RequestInterceptor {
    private String headerValue;

    public FeignRequestInterceptor() {
    }

    public FeignRequestInterceptor(String username, String password) {
        this(username, password, ISO_8859_1);
    }

    public FeignRequestInterceptor(String username, String password, Charset charset) {
        checkNotNull(username, "username");
        checkNotNull(password, "password");
        this.headerValue = "Basic " + base64encode((username + ":" + password).getBytes(charset));
    }

    private static String base64encode(byte[] bytes) {
        BASE64Encoder encoder = new BASE64Encoder();
        return encoder.encode(bytes);
    }

    @Override
    public void apply(RequestTemplate requestTemplate) {
        requestTemplate.header("Authorization", headerValue);
    }
}

I don't know how to configure this interceptor to my client and how to set the header with the username and password. How can I accomplish that ?

我不知道如何将此拦截器配置到我的客户端，以及如何使用用户名和密码设置标头。我怎样才能做到这一点？

回答by Aleksandr Erokhin

You don't really need your own implementation of the FeignRequestInterceptoras there is already BasicAuthRequestInterceptorin the feign.authpackage that does exactly the same.

您真的不需要自己的实现，FeignRequestInterceptor因为包中已经有BasicAuthRequestInterceptor的feign.auth功能完全相同。

With this said, you basically have almost everything set up already. All is left to do is to define the basicAuthRequestInterceptorbean with specific username and password:

话虽如此，您基本上已经设置了几乎所有内容。剩下要做的就是定义basicAuthRequestInterceptor具有特定用户名和密码的bean：

@Bean
public RequestInterceptor basicAuthRequestInterceptor() {
    return new BasicAuthRequestInterceptor("username", "password");
}