SpringBoot中的restTemplate请求存在乱码问题的解决

搜索网上各种解法，最后在不断的一点点对比中，排查到了问题，是restTemplate不支持gzip，对返回的数据不能对gzip自动解压，因此需要去掉header中的accept-encoding

网上提到的另一种解决方式是配置

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.apache.http.client.HttpClient;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.springframework.http.HttpHeaders;
import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
import org.springframework.web.client.RestTemplate;

@Configuration
public class RestTemplateConfig {

    @Bean
    public RestTemplate restTemplate() {
        // 创建 HttpClient
        CloseableHttpClient httpClient = HttpClients.custom()
                .setConnectionManager(new PoolingHttpClientConnectionManager())
                .build();

        // 配置 RequestFactory
        HttpComponentsClientHttpRequestFactory requestFactory = new HttpComponentsClientHttpRequestFactory(httpClient);
        RestTemplate restTemplate = new RestTemplate(requestFactory);

        // 添加请求头，告知服务器支持 Gzip
        restTemplate.getInterceptors().add((request, body, execution) -> {
            request.getHeaders().add(HttpHeaders.ACCEPT_ENCODING, "gzip, deflate, br");
            return execution.execute(request, body);
        });
        return restTemplate;
    }
}

而实际运行时还是会报错的。
一个解决方案就是 headers.remove(HttpHeaders.ACCEPT_ENCODING)，但是并不完美。

    @GetMapping("/**")
    public ResponseEntity<String> proxyGetRequest(@RequestHeader HttpHeaders headers, HttpServletRequest request) {
        String requestUri = request.getRequestURI().replace("/proxy", "");
        String targetUrl = "https://pre-youku-prefect-v2.alibaba-inc.com" + requestUri;

        headers.remove(HttpHeaders.ACCEPT_ENCODING); //必须去掉gzip压缩
        ResponseEntity<String> response = restTemplate.exchange(targetUrl, HttpMethod.GET, new HttpEntity<>(headers), String.class);
        return ResponseEntity.status(response.getStatusCode()).body(response.getBody());
    }

最终原因

再深入分析后，发现实现代理时，应返回字节流，而不能是字符流，就能完美的实现代理功能

@RestController
@RequestMapping("/proxy")
public class ProxyController {

    private final RestTemplate restTemplate;

    public ProxyController(RestTemplate restTemplate) {
        this.restTemplate = restTemplate;
    }

    @GetMapping("/**")
    public ResponseEntity<byte[]> proxyGetRequest(@RequestHeader HttpHeaders headers, HttpServletRequest request) {
        String requestUri = request.getRequestURI().replace("/proxy", "");
        String targetUrl = "https://xxx.com" + requestUri;
        ResponseEntity<byte[]> response = restTemplate.exchange(targetUrl, HttpMethod.GET, new HttpEntity<>(headers), byte[].class);
        return response;
    }

    @PostMapping("/**")
    public ResponseEntity<byte[]> proxyPostRequest(@RequestHeader HttpHeaders headers, @RequestBody String body, HttpServletRequest request) {
        String requestUri = request.getRequestURI().replace("/proxy", "");
        String targetUrl = "https://xxx.com" + requestUri;
        ResponseEntity<byte[]> response = restTemplate.exchange(targetUrl, HttpMethod.POST, new HttpEntity<>(body, headers), byte[].class);
        return response;
    }
}