"'SCPClient' object has no attribute 'SCPException'" when trying to handle an exception from SCP module for Paramiko

Question

I am writing a script for automating the delivery of files to Cisco devices, and when the device is not configured as an SCP server, I receive an error that kills my entire script.

I have added two exceptions for the other script-killing exceptions, but when I try and add it for this SCP error, I receive the following error:

try:
    ssh_client =paramiko.SSHClient()
    ssh_client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    print((time.strftime('%d-%b-%Y %H:%M:%S'))+" - Attempting SSH connection with "+ip)
    ssh_client.connect(hostname=ip,username=user,password=passw)
    print((time.strftime('%d-%b-%Y %H:%M:%S'))+" - Successfully established SSH connection with "+ip)
    scp = SCPClient(ssh_client.get_transport(), progress = progress)
    print((time.strftime('%d-%b-%Y %H:%M:%S'))+" - Transferring file to "+ip)
    scp.put(src, remote_path=dst)
    print((time.strftime('%d-%b-%Y %H:%M:%S'))+" - Successfully transferred "+src+" to "+ip)
    ssh_client.close()
    print((time.strftime('%d-%b-%Y %H:%M:%S'))+" - Closed SSH session with "+ip)
    print("###########")
    f = open("scpaudit.txt","a")
    f.write(time.strftime('%d-%b-%Y %H:%M:%S')+" "+user+" transferred "+src+" to "+ip)
    f.close()
except paramiko.ssh_exception.AuthenticationException:
    print("-> ERROR: Auth error for "+user+" on "+ip)
    print("#########")
    f = open("scpaudit.txt","a")
    f.write(time.strftime('%d-%b-%Y %H:%M:%S')+" ERROR: Authentication Error for "+user+" to "+ip)
    f.close()
except paramiko.ssh_exception.NoValidConnectionsError:
    print("-> ERROR: Unable to connect to "+ip)
    print("#########")
    f = open("scpaudit.txt","a")
    f.write(time.strftime('%d-%b-%Y %H:%M:%S')+" ERROR: Unable to connect to "+ip)
    f.close()

When I encounter a device that does not have the SCP Server enabled, I received the following error:

Traceback (most recent call last):
  File "scpscript.py", line 100, in <module>
yes_or_no("I confirm that the above information is correct and I would like to proceed. ")
  File "scpscript.py", line 93, in yes_or_no
return session()
  File "scpscript.py", line 65, in session
scp.put(src, remote_path=dst)
  File "/usr/local/lib/python2.7/dist-packages/scp.py", line 158, in put
self._recv_confirm()
   File "/usr/local/lib/python2.7/dist-packages/scp.py", line 363, in _recv_confirm
raise SCPException(asunicode(msg[1:]))
scp.SCPException: Administratively disabled.

So I then add the following exception to the end (ninja edit at 07:15 - copied the wrong exception to stackoverflow):

except scp.SCPException:
    print("-> SCP administratively disabled on remote device "+ip)

...which then results in the following error:

Traceback (most recent call last):
  File "scpscript.py", line 100, in <module>
yes_or_no("I confirm that the above information is correct and I would like to proceed. ")
  File "scpscript.py", line 93, in yes_or_no
return session()
  File "scpscript.py", line 85, in session
except scp.SCPException(asunicode(msg[:])):
AttributeError: 'SCPClient' object has no attribute 'SCPException'

Out of ideas. Is it possible that the lines in try could be organized better? I appreciate any feedback! Thank you.

Answer 1

You have a conflict between scp module name and your local scp variable.

One possible solution is to change the name of your variable. Following the ssh_client pattern, you can use scp_client:

scp_client = SCPClient(ssh_client.get_transport(), progress = progress)

scp_client.put(src, remote_path=dst)