[BUG] - paramiko recv() function not reading the psql prompt when ssh to a windows and psql command is sent about paramiko HOT 18 CLOSED

Hi,
Sorry for the inconvenience.
The issue was cause due to cygwin sshd service was not able to open any of the executables.so we changed cygwin's ssh service with openssh and it worked.

Thak you very much for the help!!!

from paramiko.

Hi @jun66j5 ,
Can I get help on this issue
It's kind of urgent here

from paramiko.

I'd suggest using Channel.exec_command instead of sending command via Channel.invoke_shell unless you are familiar with pty and shell.

Also, the script should be posted with ```...``` (code block). See https://docs.github.com/en/get-started/writing-on-github/working-with-advanced-formatting/creating-and-highlighting-code-blocks.

from paramiko.

Also, that is not a paramiko issue. It is just a support question of paramiko-expect. I'd suggest to send the question to paramiko-expect project, not here.

from paramiko.

No i mean when command is sent via channel.send()

The channel.recv() is not providing the correct output
Here is the output provided by cahnnel.recv()

b'[6npswl -U postgres Microsoft windows version [version details]. \r\r\n'

In our case expect library is failing as it's using channel.recv() and it's not providing the correct output

Looks more like paramiko issue rather than paramiko expect

We need to use channel.invoke_shell() because we need the expect like interactive shell

Whereas same works perfectly fine with linux

from paramiko.

I'd suggest using Channel.exec_command instead of sending command via Channel.invoke_shell unless you are familiar with pty and shell.

Also, the script should be posted with ```...``` (code block). See https://docs.github.com/en/get-started/writing-on-github/working-with-advanced-formatting/creating-and-highlighting-code-blocks.

My opologies.
Will follow above rules

from paramiko.

Use PGPASSWORD enviroment (or PGPASSFILE) via exec_command rather than interactive mode.

from paramiko.

We needed an interactive mode because we need to query the db and based on query output some additional queries needs to be executed based on previous outputs
Is there any way to find root cause and try to fix it?

from paramiko.

Your usage is wrong.

b'[6npswl -U postgres Microsoft windows version [version details]. \r\r\n'

Send command (psql -U ...\r\n) to the channel after receiving the prompt of cmd.exe.

from paramiko.

Same thing is done the above output is what we are getting after sending psql ...\r\n
Instead of giving psql prompt it's giving the cmd prompt

from paramiko.

We needed an interactive mode because we need to query the db and based on query output some additional queries needs to be executed based on previous outputs

If I were to do it, I'd implement it in a PowerShell script (or bat script) and run the script using exec_command from paramiko, and avoid interactive mode.

from paramiko.

We needed an interactive mode because we need to query the db and based on query output some additional queries needs to be executed based on previous outputs

If I were to do it, I'd implement it in a PowerShell script (or bat script) and run the script using exec_command from paramiko, and avoid interactive mode.

Ok thanks, but the issue is we already have pre built framework around that which worked perfectly fine with linux so we needed same script to work with window ssh

from paramiko.

Can u plz try it once if you have the windows setup
That would give a clear picture to the issue

from paramiko.

Hm, I don't have experience with shell operations on Windows Server from paramiko, and I don't think it works properly, so I can't help you.

from paramiko.

Hm, I don't have experience with shell operations on Windows Server from paramiko, and I don't think it works properly, so I can't help you.

Ok,can you point me to the right guy
That will be helpful..

from paramiko.

Works fine on my environment but I don't recommend using interactive mode if you need it unless solving it yourself.

Script

import os, re, sys, time
import paramiko

ssh_host = 'computer-name'
ssh_user = 'username'
ssh_pass = 'password'
psql_bin = r'"C:\Program Files\PostgreSQL\16\bin\psql.exe"'
psql_host = 'hostname'
psql_user = 'username'
psql_pass = 'password'
psql_dbname = 'dbname'
cmd_prompt_re = re.compile((r'^%s@\S+\s+C:\\[^>]*>' % re.escape(ssh_user)).encode('utf-8'), re.M)
psql_prompt_re = re.compile((r'^%s=[#>]' % re.escape(psql_dbname)).encode('utf-8'), re.M)

paramiko.util.log_to_file(__file__ + '.log')

def wait_for_prompt(shell, pattern):
    while True:
        while shell.recv_ready():
            data = shell.recv(1024)
            print(repr(data), file=sys.stderr, flush=True)
            if pattern.search(data):
                return
        time.sleep(1)

def wait_for_cmd_prompt(shell):
    wait_for_prompt(shell, cmd_prompt_re)

def wait_for_psql_prompt(shell):
    wait_for_prompt(shell, psql_prompt_re)

with paramiko.SSHClient() as cli:
    cli.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    cli.connect(ssh_host, username=ssh_user, password=ssh_pass)
    with cli.invoke_shell() as shell:
        wait_for_cmd_prompt(shell)
        shell.send(f'{psql_bin} --version\r\n'.encode('utf-8'))
        wait_for_cmd_prompt(shell)
        shell.send(f'set PGPASSWORD={psql_pass}\r\n'.encode('utf-8'))
        wait_for_cmd_prompt(shell)
        shell.send(f'{psql_bin} --host={psql_host} --username={psql_user} {psql_dbname}\r\n'.encode('utf-8'))
        wait_for_psql_prompt(shell)
        shell.send(b'SELECT version();\r\n')
        wait_for_psql_prompt(shell)

Results

C:>call C:\usr\src\paramiko.venv\Scripts\python.exe paramiko-windows.py
b'\x1b[2J\x1b[m\x1b[HMicrosoft Windows [Version 10.0.19045.4474]\x1b]0;C:\\WINDOWS\\system32\\conhost.exe\x07\x1b[?25h\x1b[25l\r\n(c) Microsoft Corporation. All rights reserved.\r\n\x1b[47X\r\nusername@COMPUTER-NAME C:\\Users\\username>    \x1b[4;44H\x1b]0;Administrator: C:\\WINDOWS\\system32\\conhost.exe\x07\x1b[?25h'
b'\rusername@COMPUTER-NAME C:\\Users\\username>"C:\\Program Files\\PostgreSQL\\16\\bin\\p\r\nsql.exe" --version\x1b[K\r\npsql (PostgreSQL) 16.3\x1b[21X\r\n\x1b[43X\r\nusername@COMPUTER-NAME C:\\Users\\username>'
b'set PGPASSWORD=password\r\n\r\nusername@COMPUTER-NAME C:\\Users\\username>'
b'\rusername@COMPUTER-NAME C:\\Users\\username>"C:\\Program Files\\PostgreSQL\\16\\bin\\p\r\nsql.exe" --host=192.168.11.122 --username=username dbname\x1b[K\r\n\x1b]0;Administrator: C:\\WINDOWS\\system32\\conhost.exe - "C:\\Program Files\\PostgreSQL\\16\\bin\\psql.exe"  --host=192.168.11.122 --username=username dbname\x07p\rpsql (16.3, server 9.5.25)\x1b[K\r\nSSL connection (protocol: TLSv1.2, cipher: ECDHE-RSA-AES256-GCM-SHA384, compress\r\nion: off)\x1b[K\r\nType "help" for help.\x1b[K\r\n\x1b[K\r\ndbname=>\x1b[K\x1b[1C'
b'SELECT version();\r\n                                                      version\x1b[K\r\n\x1b[K\r\n--------------------------------------------------------------------------------\r\n-----------------------------------\x1b[K\r\n PostgreSQL 9.5.25 on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 5.4.0-6ubuntu\r\n1~16.04.12) 5.4.0 20160609, 64-bit\x1b[K\r\n(1 row)\x1b[K\r\n\n\ndbname=>\x1b[1C'

from paramiko.

Ok let me check I haven't encode the send command let me check with that

from paramiko.

I don't think you should close an issue without explaining what caused it, especially when you've received help.

from paramiko.