Fiddler抓取IDEA上用HttpClient发出的网络请求

Posted 2021-09-12 二木成林

原先使用HttpClient发送请求的代码是这样的：

    public static void testHttpClient() throws IOException {
        CloseableHttpClient client = HttpClientBuilder.create().build();
        String url = "http://www.baidu.com/";
        HttpGet get = new HttpGet(url);
        try {
            HttpResponse response = client.execute(get);
            HttpEntity entity = response.getEntity();
            String result = EntityUtils.toString(entity, "UTF-8");
            System.out.println("url: " + result);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

但是我们并不能看到HTTP的请求和响应，所以需要使用Fiddler来抓包。

打开Fiddler

 查看端口号，该端口号可以修改。

 接着在IDEA中修改代码为：

    public static void testHttpClientByProxy() throws IOException {
        // 设置代理，hostname参数是本机的IP地址，port端口号是Fiddler设置的端口号
        HttpHost proxy = new HttpHost("192.168.33.35", 8888, "http");
        RequestConfig config = RequestConfig.custom().setProxy(proxy).build();
        // 设置配置
        CloseableHttpClient client = HttpClientBuilder.create().setDefaultRequestConfig(config).build();
        String url = "http://www.baidu.com/";
        HttpGet get = new HttpGet(url);
        try {
            HttpResponse response = client.execute(get);
            HttpEntity entity = response.getEntity();
            String result = EntityUtils.toString(entity, "UTF-8");
            System.out.println("url: " + result);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

核心是如下配置：

注意IP地址和端口号。

但最值得注意的还是导包，有同名的类， 应该导入org.apache.http.HttpHost，而不是httpclient包中的，尽管我们使用的是HttpClient，这个必须注意。

所以完整的代码如下：

import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.util.EntityUtils;

public class Demo {
    public static void main(String[] args) {
        testHttpClientByProxy();
//        testHttpClient();
    }

    public static void testHttpClientByProxy() {
        // 设置代理，hostname参数是本机的IP地址，port端口号是Fiddler设置的端口号
        HttpHost proxy = new HttpHost("192.168.33.55", 8888, "http");
        RequestConfig config = RequestConfig.custom().setProxy(proxy).build();
        // 设置配置
        CloseableHttpClient client = HttpClientBuilder.create().setDefaultRequestConfig(config).build();
        String url = "http://www.baidu.com/";
        HttpGet get = new HttpGet(url);
        try {
            HttpResponse response = client.execute(get);
            HttpEntity entity = response.getEntity();
            String result = EntityUtils.toString(entity, "UTF-8");
            System.out.println("url: " + result);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static void testHttpClient() {
        CloseableHttpClient client = HttpClientBuilder.create().build();
        String url = "http://www.baidu.com/";
        HttpGet get = new HttpGet(url);
        try {
            HttpResponse response = client.execute(get);
            HttpEntity entity = response.getEntity();
            String result = EntityUtils.toString(entity, "UTF-8");
            System.out.println("url: " + result);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

}

我们是使用百度作为测试网站的，启动IDEA中的程序，查看Fiddler

 注意，在Fiddler设置了只抓取非浏览器请求

 控制台也会成功输出