Spring Boot Feign服务调用之间带token

朴灿烈づ我的快乐病毒、 2022-05-15 04:38 150阅读 0赞

# Spring Boot 使用Feign服务调服务传递数据带token验证 #

> **Feign服务调服务就不多做介绍了，值得提醒的是，Feign服务调服务传递数据的时候，比如某用户服务是需要带token验证的，而调用那个用户服务的时候报错，提示token为空，是因为Feign请求的时候没有带上token**

## 解决方式 ##

要解决这个问题，想必能猜到最方便的就是往请求头里加上token，一起带过去

### Feign有提供一个接口，`RequestInterceptor` ###

只要实现这个接口，简单做一些处理，比如说我们验证请求头的token叫`Access-Token`，我们就先取出当前请求的token，然后放到feign请求头上

import feign.RequestInterceptor;
    import feign.RequestTemplate;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.web.context.request.RequestContextHolder;
    import org.springframework.web.context.request.ServletRequestAttributes;
    
    import javax.servlet.http.HttpServletRequest;
    
    /** * Feign配置 * 使用FeignClient进行服务间调用，传递headers信息 */
    @Configuration
    public class FeignConfig implements RequestInterceptor { 
        @Override
        public void apply(RequestTemplate requestTemplate) {
            ServletRequestAttributes attributes = (ServletRequestAttributes)RequestContextHolder.getRequestAttributes();
            HttpServletRequest request = attributes.getRequest();
            //添加token
            requestTemplate.header("Access-Token", request.getHeader("Access-Token"));
        }
    }

### 这样已经成功往Feign请求头里加上了Token，还可以这样，为了方便本地调试，可以在Spring Boot加上过滤器，每次本地调用没有Token的时候加上一个，只要实现Spring提供的`Filter`接口 ###

import org.apache.commons.lang3.StringUtils;
    
    import javax.servlet.*;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletRequestWrapper;
    import java.io.IOException;
    
    /** * 每次请求过滤器拦截加Token */
    public class AddTokenFilter implements Filter { 
    
        /** * superAdmin */
        private static final String DEFAULT_TOKEN = "你的token";
    
        private String profilesActive;
    
        public AddTokenFilter(String profilesActive) {
            super();
            this.profilesActive = profilesActive;
        }
    
        @Override
        public void init(FilterConfig filterConfig) throws ServletException {
    
        }
    
        @Override
        public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
         //判断是开发模式（dev）还是生产坏境（pro）
         //如果不是开发坏境，不做任何操作，是开发坏境，往本地测试的request加请求头
            if (profilesActive == null || !EnumEnvType.DEV.toString().equalsIgnoreCase(profilesActive)) {
    
                filterChain.doFilter(servletRequest, servletResponse);
                return;
            }
            filterChain.doFilter(new CustomeizedRequest((HttpServletRequest) servletRequest), servletResponse);
        }
    
        @Override
        public void destroy() {
    
        }
    //继承HttpServletRequestWrapper ，重写getHeader获取请求头的值
        private class CustomeizedRequest extends HttpServletRequestWrapper { 
    
            /** * Constructs a request object wrapping the given request. * * @param request * @throws IllegalArgumentException if the request is null */
            public CustomeizedRequest(HttpServletRequest request) {
                super(request);
            }
    
    
            @Override
            public String getHeader(String name) {
                if (!Constant.HTTP_HEADER_ACCESS_TOKEN.equalsIgnoreCase(name)) {
                    return super.getHeader(name);
                }
                String token = super.getHeader(name);
                return StringUtils.isNotBlank(token) ? token : DEFAULT_TOKEN;
            }
        }
    
    }

使用这个Filter很简单，新建一个`WebMvcConfig`类，配置一个bean

import com.alibaba.fastjson.serializer.SerializerFeature;
    import com.alibaba.fastjson.support.config.FastJsonConfig;
    import com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter;
    import com.uhope.rl.watersource.filter.AddTokenFilter;
    import com.uhope.rl.watersource.filter.ServiceFilter;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.boot.autoconfigure.web.HttpMessageConverters;
    import org.springframework.boot.web.servlet.FilterRegistrationBean;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.http.converter.HttpMessageConverter;
    import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
    import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
    
    import java.nio.charset.Charset;
    
    /** * Spring MVC 配置 * @author chenbin on 2017/12/25 * @version 3.0.0 */
    @Configuration
    public class WebMvcConfig extends WebMvcConfigurerAdapter { 
    
        private final Logger logger = LoggerFactory.getLogger(WebMvcConfig.class);
    
        /** * 当前激活的配置文件 */
        @Value("${spring.profiles.active}")
        private String env;
    
        /** * 解决路径资源映射问题 * * @param registry */
        @Override
        public void addResourceHandlers(ResourceHandlerRegistry registry) {
            registry.addResourceHandler("swagger-ui.html").addResourceLocations("classpath:/META-INF/resources/");
            registry.addResourceHandler("/webjars/**").addResourceLocations("classpath:/META-INF/resources/webjars/");
            registry.addResourceHandler("/static/**").addResourceLocations("classpath:/static/");
        }
    
        /** * 使用fastJson代替Jackjson解析JSON数据 * * @return */
        @Bean
        public HttpMessageConverters fastJsonHttpMessageConverters() {
            FastJsonHttpMessageConverter fastConverter = new FastJsonHttpMessageConverter();
            FastJsonConfig fastJsonConfig = new FastJsonConfig();
            /* * 转换为JSON字符串，默认: * WriteNullListAsEmpty List字段如果为null,输出为[],而非null * WriteNullStringAsEmpty 字符类型字段如果为null,输出为”“,而非null * WriteMapNullValue 是否输出值为null的字段,默认为false */
            fastJsonConfig.setSerializerFeatures(SerializerFeature.WriteNullListAsEmpty, SerializerFeature.WriteNullStringAsEmpty, SerializerFeature.WriteMapNullValue, SerializerFeature.WriteDateUseDateFormat);
            fastConverter.setFastJsonConfig(fastJsonConfig);
            fastConverter.setDefaultCharset(Charset.forName("UTF-8"));
            HttpMessageConverter<?> converter = fastConverter;
            return new HttpMessageConverters(converter);
        }
    
    
        /** * 这个Filter 解决页面跨域访问问题 */
        @Bean
        public FilterRegistrationBean omsFilter() {
            FilterRegistrationBean registration = new FilterRegistrationBean();
            registration.setFilter(new ServiceFilter());
            registration.addUrlPatterns("/*");
            registration.setName("MainFilter");
            registration.setAsyncSupported(true);
            registration.setOrder(1);
            return registration;
        }
    
        /** * 这个Filter 添加token */
        @Bean
        public FilterRegistrationBean addTokenFilter(){
            FilterRegistrationBean registration = new FilterRegistrationBean();
            registration.setFilter(new AddTokenFilter(env));
            registration.addUrlPatterns("/*");
            registration.setName("addTokenFilter");
            registration.setAsyncSupported(true);
            registration.setOrder(2);
            return registration;
        }
    }

## 结语 ##

这样就实现了开发坏境下添加本地测试的token，若不是开发坏境，用网页请求过来的token，很方便，也解决了Feign丢失请求头的问题