Script won't exit because paramiko thread is still running

[jsheedy]

The following script works and "FINISH" is printed, but it never exits to the shell:

import threading

from sshtunnel import SSHTunnelForwarder

with SSHTunnelForwarder(
    "localhost",
    ssh_username="localuser",
    ssh_password="localpass",
    remote_bind_address=('127.0.0.1', 5984),
    local_bind_address=('127.0.0.1', 9000)
) as server:

    print(server.local_bind_port)
    # these don't help
    # server.stop()
    # server.close()

# [t.close() for t in threading.enumerate() if t.__class__.__name__ == "Transport"]

print('FINISH!')

Python is waiting on threads to finish, but they never do. After running this script in iPython I can see the threads:

threading.enumerate()
[<_MainThread(MainThread, started 140735243972608)>,
 <HistorySavingThread(IPythonHistorySavingThread, started 123145307557888)>,
 <paramiko.Transport at 0x3880470 (cipher aes128-ctr, 128 bits) (connected; awaiting auth)>,
 <paramiko.Transport at 0x3874630 (cipher aes128-ctr, 128 bits) (connected; awaiting auth)>,
 <paramiko.Transport at 0x3191ba8 (cipher aes128-ctr, 128 bits) (connected; awaiting auth)>,
 <paramiko.Transport at 0x3874550 (cipher aes128-ctr, 128 bits) (active; 0 open channel(s))>,
 <paramiko.Transport at 0x3191c88 (cipher aes128-ctr, 128 bits) (connected; awaiting auth)>,
 <paramiko.Transport at 0x387bac8 (cipher aes128-ctr, 128 bits) (connected; awaiting auth)>,
 <paramiko.Transport at 0x3803e48 (cipher aes128-ctr, 128 bits) (connected; awaiting auth)>,
 <paramiko.Transport at 0x3874f60 (cipher aes128-ctr, 128 bits) (connected; awaiting auth)>]

If I uncomment the last line which explicitly closes the paramiko.Transport threads, the script exits correctly. It seems like I'm missing something, but even so this default behavior is confusing.

[fernandezcuesta]

Thanks for reporting, will have a look shortly.
Which version are you using BTW?

[jsheedy]

Thanks for looking into it! I just installed with pip. It got sshtunnel-0.1.0, paramiko-2.0.2, and pyasn1-0.1.9.

[fernandezcuesta]

Hi, could you please install from source (v0.1.0 branch) and retry?
Thx!

[jsheedy]

I tried installing the v0.1.0 branch and it is exiting correctly now. Thank you!

[nmz787]

I am using 0.1.3 and if I try using sshtunnel from an interactive prompt, then exiting with CTRL-D, my session never closes. But if I explicitly call stop() then CTRL-D my session exits immediately. I tried using atexit but it didn't work for me. I also tried setting sshtunnel.DAEMON=True but that also didn't help.

[kylepolich]

Any fix for this?

[theoaf]

Experiencing the same problem

[bmetea]

I'm experiencing this too, any fix?

[hshe]

I'm experiencing this too, any fix?

[stobra]

I was able to close the the connection after setting daemon_forward_servers = True

ssh_server = SSHTunnelForwarder(
        ssh_address_or_host= '98.123.89.123',
        ssh_username= 'name',
        ssh_pkey=pkey,
        remote_bind_address=(hostname, 1234))
ssh_server.daemon_forward_servers = True

with ssh_server as ssh:
        ssh.start()
        local_port = str(ssh.local_bind_port)
        conn = create_engine(f'mysql+pymysql://mysqldatabase:{local_port}')

[eykamp]

@stobra Thank you! When I set things up exactly this way they worked. Even a small deviation resulted in the hanging problem.

[dem82]

@stobra Thank you! I've solved the hanging problem with your suggestion

[stobra]

@dem82, I'm glad to hear it was helpful. Best wishes

[franz101]

@stobra you sir are a legend!

[mwharton3]

Worked for me too, thank you so much!

[pahaz]

Because someone still finds this issue through a search I'll write it here:

1. sshtunnel is always waiting until closing all connections during the stop() called.
2. If you don't want to wait, you can use .stop(force=True)
3. You can have a problem with hangs if you don't call .stop. For example, you have some unhandled exception in MainThread and you don't call .stop in this case. As a dirty workaround, you can use this hack at the beginning:

# I don't recommend to use this hack!
# Hack threadings https://docs.python.org/3/library/threading.html#threading.Thread.daemon ...
sshtunnel.SSHTunnelForwarder.daemon_forward_servers = True
sshtunnel.SSHTunnelForwarder.daemon_transport = True

4. It's better to use with open_tunnel(...) which always stops the tunnel.

Please, don't leave a comment here. If you have any issues and still have any issues feel free to open a new one!