python paramiko invoke_shell_使用Paramiko在Python上用ssh實作互動式shell？

我想編寫一個程式(在

Windows 7上的

Python 3.x中),它通過ssh在遠端shell上執行多個指令.在檢視paramikos的exec_command()函數之後,我意識到它不适合我的用例(因為在執行指令後通道被關閉),因為指令依賴于環境變量(由先前的指令設定)并且不能連接配接到一個exec_command()調用,因為它們将在程式中的不同時間執行.

是以,我想在同一個通道中執行指令.我研究的下一個選項是使用paramikos的invoke_shell()函數實作互動式shell：

ssh = paramiko.SSHClient()

ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())

ssh.connect(host, username=user, password=psw, port=22)

channel = ssh.invoke_shell()

out = channel.recv(9999)

channel.send('cd mivne_final\n')

channel.send('ls\n')

while not channel.recv_ready():

time.sleep(3)

out = channel.recv(9999)

print(out.decode("ascii"))

channel.send('cd ..\n')

channel.send('cd or_fail\n')

channel.send('ls\n')

while not channel.recv_ready():

time.sleep(3)

out = channel.recv(9999)

print(out.decode("ascii"))

channel.send('cd ..\n')

channel.send('cd simulator\n')

channel.send('ls\n')

while not channel.recv_ready():

time.sleep(3)

out = channel.recv(9999)

print(out.decode("ascii"))

ssh.close()

這段代碼存在一些問題：

>第一次列印并不總是列印ls輸出(有時它隻列印在第二次列印時).

>第一個cd和ls指令始終存在于輸出中(我通過recv指令擷取它們,作為輸出的一部分),而有時會列印以下所有cd和ls指令,有時它們不會.

>第二個和第三個cd和ls指令(列印時)總是出現在第一個ls輸出之前.

我對這種“非決定論”感到困惑,非常感謝你的幫助.

import paramiko

import re

class ShellHandler:

def __init__(self, host, user, psw):

self.ssh = paramiko.SSHClient()

self.ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())

self.ssh.connect(host, username=user, password=psw, port=22)

channel = self.ssh.invoke_shell()

self.stdin = channel.makefile('wb')

self.stdout = channel.makefile('r')

def __del__(self):

self.ssh.close()

def execute(self, cmd):

"""

:param cmd: the command to be executed on the remote computer

:examples: execute('ls')

execute('finger')

execute('cd folder_name')

"""

cmd = cmd.strip('\n')

self.stdin.write(cmd + '\n')

finish = 'end of stdOUT buffer. finished with exit status'

echo_cmd = 'echo {} $?'.format(finish)

self.stdin.write(echo_cmd + '\n')

shin = self.stdin

self.stdin.flush()

shout = []

sherr = []

exit_status = 0

for line in self.stdout:

if str(line).startswith(cmd) or str(line).startswith(echo_cmd):

# up for now filled with shell junk from stdin

shout = []

elif str(line).startswith(finish):

# our finish command ends with the exit status

exit_status = int(str(line).rsplit(maxsplit=1)[1])

if exit_status:

# stderr is combined with stdout.

# thus, swap sherr with shout in a case of failure.

sherr = shout

shout = []

break

else:

# get rid of 'coloring and formatting' special characters

shout.append(re.compile(r'(\x9B|\x1B\[)[0-?]*[ -/]*[@-~]').sub('', line).

replace('\b', '').replace('\r', ''))

# first and last lines of shout/sherr contain a prompt

if shout and echo_cmd in shout[-1]:

shout.pop()

if shout and cmd in shout[0]:

shout.pop(0)

if sherr and echo_cmd in sherr[-1]:

sherr.pop()

if sherr and cmd in sherr[0]:

sherr.pop(0)

return shin, shout, sherr