How to copy a file to a remote server in Python using SCP or SSH?

Question

I have a text file on my local machine that is generated by a daily Python script run in cron.

I would like to add a bit of code to have that file sent securely to my server over SSH.

Solution 1

You can call the scp bash command (it copies files over SSH) with subprocess.run:

import subprocess
subprocess.run(["scp", FILE, "USER@SERVER:PATH"])
#e.g. subprocess.run(["scp", "foo.bar", "[email protected]:/path/to/foo.bar"])

If you're creating the file that you want to send in the same Python program, you'll want to call subprocess.run command outside the with block you're using to open the file (or call .close() on the file first if you're not using a with block), so you know it's flushed to disk from Python.

You need to generate (on the source machine) and install (on the destination machine) an ssh key beforehand so that the scp automatically gets authenticated with your public ssh key (in other words, so your script doesn't ask for a password).

Solution 2

To do this in Python (i.e. not wrapping scp through subprocess.Popen or similar) with the Paramiko library, you would do something like this:

import os
import paramiko

ssh = paramiko.SSHClient() 
ssh.load_host_keys(os.path.expanduser(os.path.join("~", ".ssh", "known_hosts")))
ssh.connect(server, username=username, password=password)
sftp = ssh.open_sftp()
sftp.put(localpath, remotepath)
sftp.close()
ssh.close()

(You would probably want to deal with unknown hosts, errors, creating any directories necessary, and so on).

Solution 3

You'd probably use the subprocess module. Something like this:

import subprocess
p = subprocess.Popen(["scp", myfile, destination])
sts = os.waitpid(p.pid, 0)

Where destination is probably of the form user@remotehost:remotepath. Thanks to @Charles Duffy for pointing out the weakness in my original answer, which used a single string argument to specify the scp operation shell=True - that wouldn't handle whitespace in paths.

The module documentation has examples of error checking that you may want to perform in conjunction with this operation.

Ensure that you've set up proper credentials so that you can perform an unattended, passwordless scp between the machines. There is a stackoverflow question for this already.

Solution 4

Reached the same problem, but instead of "hacking" or emulating command line:

Found this answer here.

from paramiko import SSHClient
from scp import SCPClient

ssh = SSHClient()
ssh.load_system_host_keys()
ssh.connect('example.com')

with SCPClient(ssh.get_transport()) as scp:
    scp.put('test.txt', 'test2.txt')
    scp.get('test2.txt')

Solution 5

You can do something like this, to handle the host key checking as well

import os
os.system("sshpass -p password scp -o StrictHostKeyChecking=no local_file_path username@hostname:remote_path")

View more solutions

Comments

[Charles Duffy]

Using subprocess.Popen is the Right Thing. Passing it a string rather than an array (and using shell=True) is the Wrong Thing, as it means filenames with spaces don't work correctly.

[searchingpruegel]

paramiko has a nice sftp.put(self, localpath, remotepath, callback=None) function too, so you don't have to open write, and close each file.

[db42]

instead of "sts = os.waitpid(p.pid, 0)", we can use "sts = p.wait()".

[Drahkar]

I would note that SFTP is not the same thing as SCP.

[whyoz]

@Drahkar the question asks for the file to be sent over SSH. That's what this does.

[doda]

Note: to make this work out of the box add ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) after instantiating ssh.

[Tom]

@doda only if you don't want to use the known_hosts file

[László Papp]

Any idea for an "scp" based solution? SFTP does not work with our server.

[László Papp]

is there an execution free way of it with direct python API for this protocol?

[jfs]

@CharlesDuffy: subprocess.check_call(['scp', srcfile, dest]) could be used since Python 2.5 instead of rc = Popen(..).wait(); if rc != 0: raise ..

[jfs]

subprocess.check_call(['scp', myfile, destination]) could be used instead since Python 2.5 (2006)

[László Papp]

@J.F.Sebastian: yep, I checked it out in December. My upvotes prove that, at least. :) Thanks for the follow-up though.

[orezvani]

adding ssh key is not a good solution when it is not needed. For example, if you need a one time communication, you don't set up ssh key due to security reasons.

[Aysennoussi]

Guys, is it safe to use the server password ? is there a possibility to use the Private Key ?

[Joel B]

It's certainly possible to use a private key: gist.github.com/batok/2352501

[Chuck]

Note - this relies on the scp package. As of Dec 2017, the latest update to that package was in 2015 and the version number is 0.1.x. Not sure I would want to add this dependency.

[Adriano_Pinaffo]

so, it´s 2018 now and in may they released version 0.11.0. So, it seems SCPClient is not dead after all?

[WinEunuuchs2Unix]

Interesting that this answer has almost three-fold more votes than accepted answer.

[volkit]

the scp module is regulary updated (last was in June 2021) and has 380 stars on github. this is a legit solution.

[Can H. Tartanoglu]

@WinEunuuchs2Unix why?

[WinEunuuchs2Unix]

@CanH.Tartanoglu I guess it's called individualism. I find something interesting that you do not. You can find something interesting that I do not.

[Can H. Tartanoglu]

@WinEunuuchs2Unix I was just curious why you found it interesting. You don't have to defend yourself, everyone is entitled to an opinion. I just wanted to know because I didn't find it interesting. Cheers.