What is the difference between calling open_sftp() locally and via a separate function?

Question

In the following code, the first test passes, and the second one does not, which I find puzzling. ``` import paramiko def test1(): client = paramiko.SSHClient() client.set_missing_host_key_policy(paramiko.AutoAddPolicy()) client.connect('10.0.0.107', username='test', password='test') sftp = client.open_sftp() sftp.stat('/tmp') sftp.close() def get_sftp(): client = paramiko.SSHClient() client.set_missing_host_key_policy(paramiko.AutoAddPolicy()) client.connect('10.0.0.107', username='test', password='test') return client.open_sftp() def test2(): sftp = get_sftp() sftp.stat('/tmp') sftp.close() if __name__ == '__main__': test1() print 'test1 done' test2() print 'test2 done' ``` Here's what I get: ``` $ ./script.py test1 done Traceback (most recent call last): File "./play.py", line 25, in <module> test2() File "./play.py", line 20, in test2 sftp.stat('/tmp') File "/usr/lib/pymodules/python2.6/paramiko/sftp_client.py", line 337, in stat t, msg = self._request(CMD_STAT, path) File "/usr/l…

Accepted Answer

Ok, I've verified it on debian/python2.6/paramiko1.7.6.

The reason is that the `client` object goes out of scope in `get_sftp` (and closes the "channel"). If you cange it so you return the client:

```
import paramiko

def get_sftp():
    client = paramiko.SSHClient()
    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    client.connect('localhost', username='root', password='B4nan-purr(en)')
    return client

def test2():
    client = get_sftp()
    sftp = client.open_sftp()
    sftp.stat('/tmp')
    sftp.close()

if __name__ == "__main__":
    test2()
```

then everything will work (the function name should probably be changed..).

What is the difference between calling open_sftp() locally and via a separate function?

Solution

Problem