背景

开发爬虫程序，如果不做代理设置，本机的外网 IP 很容易被网站封掉，导致不能持续进行数据抓取。而 Selenium 作为动态网页抓取的利器，我们有必要了解一下，如何对它进行代理设置，并正常访问网页。

解决办法

1、首先申请代理 ip,正常付费的才比较靠谱。这其中包括账号、密码。

        private string proxy_Host = "域名地址";
        private int proxy_Post = 端口;
        private string proxy_UserName = "账号";
        private string proxy_PassWord = "密码";
        private string proxy_CheckURL = "检查是否正常的地址";
        private string Ex_Proxy_Name = "proxy.zip";

2、设置 chrome background.js、manifest.json

  private bool Rebuild_Extension_Proxy(string proxy_UserName, string proxy_PassWord)
        {
            bool result = false;

            FileStream zipToOpen = null;
            ZipArchive archive = null;
            ZipArchiveEntry readmeEntry = null;
            StreamWriter writer = null;
            string background = "";
            string manifest = "";

            try
            {
                background = @"
                var Global = {
                    currentProxyAouth:
                    {
                        username: '',
                        password: ''
                    }
                }

                Global.currentProxyAouth = {
                        username: '" + proxy_UserName + @"',
                        password: '" + proxy_PassWord + @"'
                }

                chrome.webRequest.onAuthRequired.addListener(
                    function(details, callbackFn) {
                        console.log('onAuthRequired >>>: ', details, callbackFn);
                        callbackFn({
                            authCredentials: Global.currentProxyAouth
                        });
                    }, {
                        urls: [""<all_urls>""]
                    }, [""asyncBlocking""]);

                chrome.runtime.onMessage.addListener(
                    function(request, sender, sendResponse) {
                        console.log('Background recieved a message: ', request);

                        POPUP_PARAMS = {};
                        if (request.command && requestHandler[request.command])
                            requestHandler[request.command] (request);
                    }
                );";

                manifest = @"
                {
                    ""version"": ""1.0.0"",
                    ""manifest_version"": 2,
                    ""name"": ""Chrome Proxy"",
                    ""permissions"": [
                        ""proxy"",
                        ""tabs"",
                        ""unlimitedStorage"",
                        ""storage"",
                        ""<all_urls>"",
                        ""webRequest"",
                        ""webRequestBlocking""
                    ],
                    ""background"": {
                        ""scripts"": [""background.js""]
                    },
                    ""minimum_chrome_version"":""22.0.0""
                }";

                zipToOpen = new FileStream(System.Environment.CurrentDirectory + "\\" + Ex_Proxy_Name, FileMode.Create);
                archive = new ZipArchive(zipToOpen, ZipArchiveMode.Update);

                readmeEntry = archive.CreateEntry("background.js");
                writer = new StreamWriter(readmeEntry.Open());
                writer.WriteLine(background);
                writer.Close();

                readmeEntry = archive.CreateEntry("manifest.json");
                writer = new StreamWriter(readmeEntry.Open());
                writer.WriteLine(manifest);
                writer.Close();
                result = true;
            }
            catch (Exception ex)
            {
                result = false;
            }
            finally
            {
                if (writer != null) { writer.Close(); writer.Dispose(); writer = null; }
                if (readmeEntry != null) { readmeEntry = null; }
                if (archive != null) { archive.Dispose(); archive = null; }
                if (zipToOpen != null) { zipToOpen.Close(); zipToOpen.Dispose(); zipToOpen = null; }
            }

            return result;
        }

3、Chrome Driver 使用代理 Proxy

                // 設置 Chrome Driver Exyension Proxy 設定
                bool isproxysetting = true;
                if (_isuseproxy)
                {
                    isproxysetting = Rebuild_Extension_Proxy(proxy_UserName, proxy_PassWord);
                }

                if (isproxysetting)
                {
                    // Driver 設定
                    options = new ChromeOptions();
                    if (_isuseproxy)
                    {
                        options.Proxy = null;
                        options.AddArguments("--proxy-server=" + proxy_Host + ":" + proxy_Post.ToString());
                        options.AddExtension(Ex_Proxy_Name);
                    }

4、测试一下我们的设置

  private Proxy_Unit.ProxyIPInfo Get_ProxyIPInfo(string Html_Content)
        {
            Proxy_Unit.ProxyIPInfo result = null;

            try
            {
                result = new Proxy_Unit.ProxyIPInfo();

                Html_Content = Html_Content.Replace("<html><head></head><body><pre style=\"word-wrap: break-word; white-space: pre-wrap;\">", "");
                Html_Content = Html_Content.Replace("</pre></body></html>", "");
                if (!Html_Content.Contains("proxy error"))
                {
                    result = JsonConvert.DeserializeObject<Proxy_Unit.ProxyIPInfo>(Html_Content);
                }
                else
                {
                    result = null;
                }
            }
            catch (Exception ex)
            {
                result = null;
            }

            return result;
        }

测试效果

成功，达到预期效果

{
    "ip":"213.182.205.185",
    "country":"IS",
    "asn":{
        "asnum":9009,
        "org_name":"M247 Ltd"
    },
    "geo":{
        "city":"Reykjavik",
        "region":"1",
        "region_name":"Capital Region",
        "postal_code":"105",
        "latitude":64.1369,
        "longitude":-21.9139,
        "tz":"Atlantic/Reykjavik",
        "lum_city":"reykjavik",
        "lum_region":"1"
    }
}

总结

我们之前测试要为 ChromeDriver 设定 Proxy 时有遇到许多困难，需要使用 Chrome Extension 的管道设定 Proxy 才成功，以上希望能让您比较好了解。