如何在后台下载FTPES密码保护文件

Question

在过去的几个星期里，我一直在乱搞很多事情，似乎找不到正确的方法。我是在统一中这样做的，当然，本质应该在一个环境中维护。

我在FTPES上有3个音频文件和一个文本文档，这将在FTP上明确显示TLS：

我已经使用以下代码成功登录，以验证该文件的存在：

WebRequest.RegisterPrefix("ftps", new FtpsWebRequestCreator());
ftpRequest = (FtpWebRequest)WebRequest.Create("ftps://" + IP + "/" + fileEndPath);
ftpRequest.Credentials = new NetworkCredential(User, Password);
ftpRequest.Method = WebRequestMethods.Ftp.GetFileSize;

ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(ValidateCertificate);
ServicePointManager.Expect100Continue = true;

ftpResponse = (FtpWebResponse)ftpRequest.GetResponse();
ftpResponse.Close();
ValidConnection = true;[/code]

尽管如此，我也成功地下载了文件的许多方式..我遇到的问题如下：

• 使用FtpWebRequest，我可以下载文件，并能够以AudioClip的形式加载文件(老实说，我不知道为什么它会随机停止工作，下载时使用stopped请求，即.)使用WWW类，但因为我似乎找不到办法把它推入后台。我试着用streamWriter编写文件，但它似乎不起作用。
• 使用UnityWebRequest，我不能登录到FTPS服务器，因为它是为基于HTTP的通信设计的。
• 使用WebClient，我能够登录到服务器(如上面所示注册前缀并将其与useSsl bool设置为true的低级别相关联)

- Using .DownloadFile not able to download file, hangs Unity Main Thread.
- Using .DownloadFileAsyn able to download the the file, but have no read permission, and Complete event never gets called to continue into loading the file using WWW.

​

我在这篇文章中使用的是WebClient.DownloadFileAsyn：

internal void Download(FileType fileType)
{
    IsDownloading = true;
    if (ValidConnection)
    {
        try
        {
            StartCoroutine(SetFileCreation());

            using (WebClient client = new WebClient())
            {
                WebRequest.RegisterPrefix("ftps", new FtpsWebRequestCreator());
                client.Credentials = new NetworkCredential(ftpUserID, ftpPassword);
                client.DownloadProgressChanged += new DownloadProgressChangedEventHandler(DownloadFileProgressChanged);
                client.DownloadFileCompleted += new AsyncCompletedEventHandler(DownloadFileCompleted);
                client.DownloadFileAsync(ftpIP, Application.dataPath + "/StreamingAssets/" + ftpFilePath, fileType);
            }
        }
        catch (WebException ex)
        {
            Debug.LogError(ex.Message + ex.StackTrace + "\n");
        }
    }
    else
        IsDownloading = false;
}

SetFileCreation()；是一个验证位置的方法，如果它存在，则覆盖，否则在继续之前创建目录。

现在我没有任何干净的代码(除了我已经展示的代码)来显示我一直在做的事情，但是如果有人能告诉我这方面的一个很好的例子(我还没有在下载FTPS in Unity中找到很多东西)，或者只是分享他们如何从底层处理这个问题，我们会非常感激的。

顺便提一句，我知道我的FTP服务器通过https://ftptest.net/和我的服务器日志(我自己托管它，所以我可以完全控制设置)显示所有正确的消息，直到RETR并传输成功的消息。

我已经看到了很多关于FTPS的文章，包括各种下载方式，不同级别的网络通信，高层次和低级别，以及如何将文件从文件夹中实时加载到Unity中。但没有什么东西能把这一切一刀切，很好，很干净。亲一下！

作为我们中的大多数人，我有更大的目标要关注，不能让这个细节继续拖延开发。

编辑(服务器日志)：

以下是我的WebClient.DownloadAsync()中的服务器日志；

(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> Connected, sending welcome message...
(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> AUTH TLS
(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> 234 Using authentication type TLS
(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> SSL connection established
(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> PBSZ 0
(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> 200 PBSZ=0
(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> PROT P
(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> 200 Protection level set to P
(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> USER Test
(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> 331 Password required for test
(000657)08/23/2018 22:51:32 - (not logged in) ([MyIP])> PASS ********
(000657)08/23/2018 22:51:32 - test ([MyIP])> 230 Logged on
(000657)08/23/2018 22:51:32 - test ([MyIP])> OPTS utf8 on
(000657)08/23/2018 22:51:32 - test ([MyIP])> 200 UTF8 mode enabled
(000657)08/23/2018 22:51:32 - test ([MyIP])> PWD
(000657)08/23/2018 22:51:32 - test ([MyIP])> 257 "/" is current directory.
(000657)08/23/2018 22:51:32 - test ([MyIP])> CWD /
(000657)08/23/2018 22:51:32 - test ([MyIP])> 250 CWD successful. "/" is current directory.
(000657)08/23/2018 22:51:32 - test ([MyIP])> TYPE I
(000657)08/23/2018 22:51:32 - test ([MyIP])> 200 Type set to I
(000657)08/23/2018 22:51:32 - test ([MyIP])> PASV
(000657)08/23/2018 22:51:32 - test ([MyIP])> 227 Entering Passive Mode ([MyIP],195,146)
(000657)08/23/2018 22:51:32 - test ([MyIP])> RETR MainQuests.txt
(000657)08/23/2018 22:51:32 - test ([MyIP])> 150 Connection accepted
(000657)08/23/2018 22:51:32 - test ([MyIP])> SSL connection for data connection established
(000657)08/23/2018 22:51:32 - test ([MyIP])> 226 Transfer OK

值得注意的是，连接是维护的。它不会关闭，因为连接设置为在文件下载完成后关闭.

下面是我在使用C#任务时获得的日志，如Dan Flanagan的示例所示：

(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> Connected, sending welcome message...
(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> AUTH TLS
(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> 234 Using authentication type TLS
(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> SSL connection established
(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> PBSZ 0
(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> 200 PBSZ=0
(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> PROT P
(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> 200 Protection level set to P
(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> USER Test
(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> 331 Password required for test
(000659)08/23/2018 22:58:10 - (not logged in) ([MyIP])> PASS ********
(000659)08/23/2018 22:58:10 - test ([MyIP])> 230 Logged on
(000659)08/23/2018 22:58:10 - test ([MyIP])> OPTS utf8 on
(000659)08/23/2018 22:58:10 - test ([MyIP])> 200 UTF8 mode enabled
(000659)08/23/2018 22:58:10 - test ([MyIP])> PWD
(000659)08/23/2018 22:58:10 - test ([MyIP])> 257 "/" is current directory.
(000659)08/23/2018 22:58:10 - test ([MyIP])> CWD /
(000659)08/23/2018 22:58:10 - test ([MyIP])> 250 CWD successful. "/" is current directory.
(000659)08/23/2018 22:58:10 - test ([MyIP])> TYPE I
(000659)08/23/2018 22:58:10 - test ([MyIP])> 200 Type set to I
(000659)08/23/2018 22:58:10 - test ([MyIP])> PASV
(000659)08/23/2018 22:58:10 - test ([MyIP])> 227 Entering Passive Mode ([MyIP],195,147)
(000659)08/23/2018 22:58:10 - test ([MyIP])> RETR MainQuests.txt
(000659)08/23/2018 22:58:10 - test ([MyIP])> 150 Connection accepted
(000659)08/23/2018 22:58:10 - test ([MyIP])> SSL connection for data connection established
(000659)08/23/2018 22:58:10 - test ([MyIP])> 426 Connection closed;    transfer aborted. (000659)08/23/2018 22:58:10 - test ([MyIP])> QUIT
(000659)08/23/2018 22:58:10 - test ([MyIP])> 221 Goodbye
(000659)08/23/2018 22:58:10 - test ([MyIP])> disconnected.

Answer 1

我剥去了我在Unity中工作的一个旧FTP下载程序脚本。您可能希望保存流资产文件夹中的文件。不过这会对你有帮助的。我用这个下载视频--他们从StreamingAssets文件夹中播放它们，但是下载器确实起了作用。

using System;
using System.Threading.Tasks;
using System.IO;
using System.Net;

public class FTPDownloader : MonoBehaviour
{

    public bool editorDownload;
    public string savePath;
    public string saveDir;
    public string username;
    public string pswd;

    public void StartDownload(string serverIP, string serverFolder, string fileName)
    {
        string url = string.Format("{0}{1}{2}{3}", "ftp://", serverIP, serverFolder, fileName);
        Task task = new Task(() =>
        {
            Download(url, fileName);
        });
        task.Start();
    }

    void Download(string url, string fileName)
    {
        if (!editorDownload)
        {
            return;
        }
        string path = Path.Combine(saveDir, fileName);

        try
        {
            if(File.Exists(path))
            {
                //already downloaded
                return;
            }
            //Debug.Log(url);
            FtpWebRequest request = (FtpWebRequest)WebRequest.Create(url);
            request.Credentials = new NetworkCredential(username, pswd);

            using (Stream ftpStream = request.GetResponse().GetResponseStream())
            using (Stream fileStream = File.Create(path))
            {
                byte[] buffer = new byte[10240];
                int read;
                int total = 0;
                while ((read = ftpStream.Read(buffer, 0, buffer.Length)) > 0)
                {
                    fileStream.Write(buffer, 0, read);
                    total += read;
                }
            }
        }
        catch (Exception e)
        {
            if (File.Exists(path))
            {
                File.Delete(path);
            }
            //Debug.Log(e.ToString());
        }
    }
}