Additional dependency FluentFTP replaced by CLR's FTP client implemen…

…tation

src/NAppUpdate.Framework/NAppUpdate.Framework.csproj

@@ -68,9 +68,6 @@
     <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
   </PropertyGroup>
   <ItemGroup>
-    <Reference Include="FluentFTP, Version=19.2.2.0, Culture=neutral, PublicKeyToken=f4af092b1d8df44f, processorArchitecture=MSIL">
-      <HintPath>..\..\..\packages\FluentFTP.19.2.2\lib\net35\FluentFTP.dll</HintPath>
-    </Reference>
     <Reference Include="System" />
     <Reference Include="System.Web" />
     <Reference Include="System.Xml" />
@@ -128,7 +125,6 @@
       <SubType>Designer</SubType>
     </EmbeddedResource>
     <None Include="NAppUpdate.snk" />
-    <None Include="packages.config" />
     <None Include="Updater\updater.exe" />
   </ItemGroup>
   <ItemGroup>

src/NAppUpdate.Framework/Sources/FtpSource.cs

@@ -16,51 +16,102 @@ public class FtpSource : IUpdateSource
 
 		private string feedBasePath => Path.GetDirectoryName(feedPath);
 
-		private FtpClient ftpClient { get; }
+		private int bufferSize = 2048;
+
+		private NetworkCredential credentials { get; }
 
 		/// <param name="hostUrl">Url of ftp server ("ftp://somesite.com/")</param>
 		/// <param name="feedPath">Local ftp path to feed ("/path/to/feed.xml")</param>
 		/// <param name="login">Login of ftp user, if needed</param>
 		/// <param name="password">Password of ftp user, if needed</param>
 		public FtpSource(string hostUrl, string feedPath, string login = null, string password = null)
 		{
-			ftpClient = new FtpClient(hostUrl);
 			HostUrl = hostUrl;
 			this.feedPath = feedPath;
 
 			if (login != null && password != null)
 			{
-				ftpClient.Credentials = new NetworkCredential(login, password);
+				credentials = new NetworkCredential(login, password);
 			}
 		}
 
 		private void TryConnectToHost()
 		{
+			var ftpConnRequest = (FtpWebRequest) FtpWebRequest.Create(HostUrl);
+			ftpConnRequest.Method = WebRequestMethods.Ftp.ListDirectory;
+			ftpConnRequest.UsePassive = true;
+			ftpConnRequest.KeepAlive = false;
+			ftpConnRequest.Credentials = credentials;
+
 			try
 			{
-				ftpClient.Connect();
+				ftpConnRequest.GetResponse();
 			}
-			catch(Exception e)
+			catch (WebException e)
 			{
 				throw new WebException($"Failed to connect to host: {HostUrl}. Error message: {e.Message}");
 			}
 		}
 
+		/// <summary>
+		/// Downloads remote file from ftp
+		/// </summary>
+		/// <param name="path">Path to file on server (example: "/path/to/file.txt")</param>
+		/// <returns>Path to saved on disk file (Temp folder)</returns>
+		private string DownloadRemoteFile(string path, string localPath = null)
+		{
+			try
+			{
+				string pathToSave = localPath ?? Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString());
+				// Create an FTP Request
+				var ftpRequest =
+					(FtpWebRequest) FtpWebRequest.Create(
+						$@"{HostUrl}{(HostUrl.EndsWith("/") ? string.Empty : "/")}{path}");
+				ftpRequest.Credentials = credentials;
+				// Set options
+				ftpRequest.UseBinary = true;
+				ftpRequest.UsePassive = true;
+				ftpRequest.KeepAlive = true;
+				// Specify the Type of FTP Request 
+				ftpRequest.Method = WebRequestMethods.Ftp.DownloadFile;
+
+				// Establish Return Communication with the FTP Server 
+				using (var ftpResponse = (FtpWebResponse) ftpRequest.GetResponse())
+				{
+					// Get the FTP Server's Response Stream 
+					using (var ftpStream = ftpResponse.GetResponseStream())
+					{
+						using (var localFileStream = new FileStream(pathToSave, FileMode.Create))
+						{
+							byte[] byteBuffer = new byte[bufferSize];
+							int bytesRead = ftpStream.Read(byteBuffer, 0, bufferSize);
+
+							while (bytesRead > 0)
+							{
+								localFileStream.Write(byteBuffer, 0, bytesRead);
+								bytesRead = ftpStream.Read(byteBuffer, 0, bufferSize);
+							}
+						}
+					}
+				}
+
+				return pathToSave;
+			}
+			catch (Exception ex)
+			{
+				throw new WebException(
+					$"An error occurred when trying to download file {Path.GetFileName(path)}: {ex.Message}");
+			}
+		}
+
 		#region IUpdateSource Members
 
 		public String GetUpdatesFeed()
 		{
 			TryConnectToHost();
 
-			string data = null;
-
-			using (var fileStream = ftpClient.OpenRead(feedPath, FtpDataType.ASCII, true))
-			{
-				using (var streamReader = new StreamReader(fileStream))
-				{
-					data = streamReader.ReadToEnd();
-				}
-			}
+			string feedFilePath = DownloadRemoteFile(feedPath);
+			string data = File.ReadAllText(feedFilePath);
 
 			// Remove byteorder mark if necessary
 			int indexTagOpening = data.IndexOf('<');
@@ -72,9 +123,10 @@ public String GetUpdatesFeed()
 			return data;
 		}
 
-		public Boolean GetData(String filePath, String basePath, Action<UpdateProgressInfo> onProgress, ref String tempLocation)
+		public Boolean GetData(String filePath, String basePath, Action<UpdateProgressInfo> onProgress,
+			ref String tempLocation)
 		{
-			ftpClient.DownloadFile(tempLocation, Path.Combine(feedBasePath, filePath));
+			DownloadRemoteFile(Path.Combine(feedBasePath, filePath), tempLocation);
 			return true;
 		}