Today I was working on a utility which need to upload data on
FTP. I have implemented code to upload on FTP using FTP web request. But end of
the day when I finally deployed the code, I received the details of SFTP
account with host, username, password and port. When I configured these details
in utility the utility has failed to upload file on FTP.
Then I started researching reason of failure and found that
.Net don’t support secured FTP i. e. SFTP. After searching over net I found
that we need to use third party library to upload files on SFTP while using
with .Net. There are many third party libraries available for SFTP, two of them
are given below that could be used for this purpose.
1. Rebex SFTP
2. SharpSSH
SharpSSH is open source library and published with BSD License. I have
decided to use this one for SFTP functionality implementation.
SharpSSH is a pure .NET implementation of the SSH2 client protocol suite. It provides an API for communication with SSH servers and could be integrated into any .NET application.
I am just going to discuss quick integration of this library
to implement SFTP functionality in your application. You can download source
code or DLLs for SharpSSH here.
Sharp SSH is actually using some java library and commands to
support SFTP which is covered in a wrapper to work with .Net.
You will get following three DLLs in download
1. Tamir.SharpSSH.dll
2. Org.Mentalis.Security.dll
3. DiffieHellman.dll
You need to add reference to Tamir.SharpSSH while two other
DLLs should also be referenced or added in bin. Org.Mentalis.Security dll is
used for encryption. Now let’s come directly to the small piece of code which
is doing SFTP here.
//Include namespace for Tamir.SharpSSH and System.IO as below.
using Tamir.SharpSsh;
using System.IO;
//Collect SFTP account details and root directory to upload
file in.
string m_FTPServerAddress = "x.x.x.x";
// this is host IP or host domain name
string m_FTPUser = "username";
// this is username as needed to access SFTP
string m_FTPPassword = "Password";
// this is password as needed to access SFTP
string m_FTPPort = "Port";
//this is port number which is configured in SFTP for
communucation.
string m_RemoteFTPFolder = "/RootFolderName/";
// this is root folder name as configured in SFTP.
string filePathAndName = "File
path"; //This is cmplete file name with
physical path.
//Create object for SFTP class as in
Tamir.SharpSSH dll.
Sftp scp = new Sftp(m_FTPServerAddress, m_FTPUser,
m_FTPPassword);
//Connect to SFTP using port as
provided.
scp.Connect(m_FTPPort.ToIntSafe());
//Put/upload file on SFTP from source
location to destination location in SFTP root directory.
scp.Put(filePathAndName, m_RemoteFTPFolder + Path.GetFileName(filePathAndName));
//Close connection from SFTP after
uploading.
scp.Close();
Now refer above code and notice three magical lines which are
doing actual job here as below.
1. Following line
of code creates an object of a SFTP class as in Tamir.SharpSSH using available
ftp server address which is host ip/name, SFTP user name and SFTP password.
Sftp scp = new Sftp(m_FTPServerAddress, m_FTPUser,
m_FTPPassword);
2.
Following line connects and creates a communication channel between
application and SFTP host using specific post as provided in “m_FTPPort”
variable.
scp.Connect(m_FTPPort.ToIntSafe());
3. Following line
of code uploads file from source path to destination path on Sftp root.
//scp.Put(source_file,
destination_file);
scp.Put(filePathAndName, m_RemoteFTPFolder + Path.GetFileName(filePathAndName));
4. Following line
of code finally closes connection and communication channel from SFTP host.
scp.Close();
The code as explained above is tested and working properly.
While I was trying to implement this code I came with an exception with no
information in it. But after researching and trying I come to know that I was
giving just file name in destination file as specified in point 3. While root
folder of SFTP was needed as prefixed with file name to successfully upload file
on SFTP server.
I just mentioned above point so that no one other should
stuck in such a small problem.
Now enjoy SFTP upload just like normal FTP upload.
