SpringCloud RestTemplate通过拦截器统一添加token

写在前面：在进行本地远程调用时如果没有携带token在调某些接口时可能会报401，所以简单实现一个通过拦截器实现对RestTemplate统一添加token，这样再业务中通过restTemplate发起远程调用时，无需再传token即可进行调用。

下面直接上代码吧：

拦截器：

package xxxxxx;

import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpRequest;
import org.springframework.http.client.ClientHttpRequestExecution;
import org.springframework.http.client.ClientHttpRequestInterceptor;
import org.springframework.http.client.ClientHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
import java.util.List;

/**
 * @author 
 * @description RestTemplate 统一添加 access_token 拦截器
 * @date 2020/6/2
 * @projectName share-capacity-platform
 */
@Component
public class HeaderRequestInterceptor implements ClientHttpRequestInterceptor {

    @Override
    public ClientHttpResponse intercept(HttpRequest httpRequest, byte[] body, ClientHttpRequestExecution clientHttpRequestExecution) throws IOException {
        RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
        HttpServletRequest request = ((ServletRequestAttributes) requestAttributes).getRequest();
        String auth = request.getHeader("Authorization");
        String accessToken = request.getParameter("access_token");
        List<String> authorizations = httpRequest.getHeaders().get("Authorization");
        String authorization = "";
        if (accessToken != null){
            authorization = "bearer " + accessToken;
        }else if (auth != null){
            authorization = auth;
        }else if (authorizations != null){
            authorization = "bearer " + authorizations.get(0);
        }
        HttpHeaders headers = httpRequest.getHeaders();
        headers.add("Authorization", authorization);
        return clientHttpRequestExecution.execute(httpRequest, body);
    }
}

RestTemplateConfig：

package xxxxxx;
/*
 * Copyright (c) 2005, 2019, EVECOM Technology Co.,Ltd. All rights reserved.
 * EVECOM PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */

import org.apache.http.client.HttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
import org.springframework.web.client.DefaultResponseErrorHandler;
import org.springframework.web.client.RestTemplate;

import java.util.Collections;

/**
 * <P><B>Description: </B> 描述  </P>
 * Revision Trail: (Date/Author/Description)
 * 2019/7/18
 * @version 1.0
 */
@Configuration
public class RestTemplateConfig {

    @Autowired
    HeaderRequestInterceptor headerRequestInterceptor;

    @Bean
    @LoadBalanced
    public RestTemplate restTemplate() {
        // 长连接
        PoolingHttpClientConnectionManager pollingConnectionManager = new PoolingHttpClientConnectionManager();
        // 总连接数
        pollingConnectionManager.setMaxTotal(1000);
        // 同路由的并发数
        pollingConnectionManager.setDefaultMaxPerRoute(1000);

        HttpClientBuilder httpClientBuilder = HttpClients.custom();
        httpClientBuilder.setConnectionManager(pollingConnectionManager);
        // 重试次数，默认是3次，没有开启
        // httpClientBuilder.setRetryHandler(new DefaultHttpRequestRetryHandler(3,
        // true));
        HttpClient httpClient = httpClientBuilder.build();

        HttpComponentsClientHttpRequestFactory clientHttpRequestFactory = new HttpComponentsClientHttpRequestFactory(
                httpClient);
        // 连接超时
        clientHttpRequestFactory.setConnectTimeout(60000);
        // 数据读取超时时间，即SocketTimeout
        clientHttpRequestFactory.setReadTimeout(60000);
        // 连接不够用的等待时间，不宜过长，必须设置，比如连接不够用时，时间过长将是灾难性的
        clientHttpRequestFactory.setConnectionRequestTimeout(200);
        // 缓冲请求数据，默认值是true。通过POST或者PUT大量发送数据时，建议将此属性更改为false，以免耗尽内存。
        RestTemplate restTemplate = new RestTemplate();
        //set拦截器统一添加token
        restTemplate.setInterceptors(Collections.singletonList(headerRequestInterceptor));
        restTemplate.setRequestFactory(clientHttpRequestFactory);
        restTemplate.setErrorHandler(new DefaultResponseErrorHandler());

        return restTemplate;
    }
}

总结：

通过拦截器将token添加到请求头中，然后在RestTemplateConfig 配置类中添加该拦截器，即可简单实现RestTemplate统一添加token。