pythonsshsftpparamiko

Upload files using SFTP in Python, but create directories if path doesn't exist


I want to upload a file on a remote server with Python. I'd like to check beforehand if the remote path is really existing, and if it isn't, to create it. In pseudocode:

if(remote_path not exist):
    create_path(remote_path)
upload_file(local_file, remote_path)

I was thinking about executing a command in Paramiko to create the path (e.g. mkdir -p remote_path). I came up with this:

# I didn't test this code

import paramiko, sys

ssh = paramiko.SSHClient()
ssh.connect(myhost, 22, myusername, mypassword)
ssh.exec_command('mkdir -p ' + remote_path)
ssh.close

transport = paramiko.Transport((myhost, 22))
transport.connect(username = myusername, password = mypassword)

sftp = paramiko.SFTPClient.from_transport(transport)
sftp.put(local_path, remote_path)
sftp.close()

transport.close()

But this solution doesn't sound good to me, because I close the connection and then reopen it again. Is there a better way to do it?


Solution

  • SFTP supports the usual FTP commands (chdir, mkdir, etc...), so use those:

    sftp = paramiko.SFTPClient.from_transport(transport)
    try:
        sftp.chdir(remote_path)  # Test if remote_path exists
    except IOError:
        sftp.mkdir(remote_path)  # Create remote_path
        sftp.chdir(remote_path)
    sftp.put(local_path, '.')    # At this point, you are in remote_path in either case
    sftp.close()
    

    To fully emulate mkdir -p, you can work through remote_path recursively:

    import os.path
    
    def mkdir_p(sftp, remote_directory):
        """Change to this directory, recursively making new folders if needed.
        Returns True if any folders were created."""
        if remote_directory == '/':
            # absolute path so change directory to root
            sftp.chdir('/')
            return
        if remote_directory == '':
            # top-level relative directory must exist
            return
        try:
            sftp.chdir(remote_directory) # sub-directory exists
        except IOError:
            dirname, basename = os.path.split(remote_directory.rstrip('/'))
            mkdir_p(sftp, dirname) # make parent directories
            sftp.mkdir(basename) # sub-directory missing, so created it
            sftp.chdir(basename)
            return True
    
    sftp = paramiko.SFTPClient.from_transport(transport)
    mkdir_p(sftp, remote_path) 
    sftp.put(local_path, '.')    # At this point, you are in remote_path
    sftp.close()
    

    Of course, if remote_path also contains a remote file name, then it needs to be split off, the directory being passed to mkdir_p and the filename used instead of '.' in sftp.put.