flutter Charles 抓包动态获取代理ip

一.关于Charles的下载和配置可以参考Charles https 抓包

二.关于flutter dio设置代理

简单说下几种方式：

1.一种是运行的时候直接设置

首先在dio初始化后直接设置如下

  void checkForCharlesProxy(Dio dio) {
    const charlesIp =
    String.fromEnvironment('CHARLES_PROXY_IP', defaultValue: null);
    if (charlesIp == null) return;
    debugPrint('#CharlesProxyEnabled');
    (dio.httpClientAdapter as DefaultHttpClientAdapter).onHttpClientCreate =
        (client) {
      client.findProxy = (uri) => "PROXY $charlesIp:8888;";
      client.badCertificateCallback =
          (X509Certificate cert, String host, int port) => true;
    };
  }

然后用命令行运行，ip换成自己的就可以了，例如

flutter run --dart-define=CHARLES_PROXY_IP=192.168.0.52

以上方法参照https://medium.com/netguru/how-to-connect-charles-proxy-with-dio-4443af7bbaa8，开发自己用挺好，但不方便给测试使用。

2.另外一种是利用第三方插件http_proxy

自动获取手机的代理，然后dio创建后设置
代码如下：

import 'package:http_proxy/http_proxy.dart';

void checkForCharlesProxy(Dio dio) async {
    HttpProxy httpProxy = await HttpProxy.createHttpProxy();
    var proxyHost = httpProxy.host;
    var proxyPort = httpProxy.port;
    if (proxyHost == null) return;
    (dio.httpClientAdapter as DefaultHttpClientAdapter).onHttpClientCreate =
        (client) {
      client.findProxy = (uri) => "PROXY $proxyHost:$proxyPort;";
      client.badCertificateCallback =
          (X509Certificate cert, String host, int port) => true;
    };
  }

目前测试过几个手机，都能成功抓包，这样给测试打的包也可以抓包了