如何在Paramiko的单个会话中执行多个命令？(蟒蛇)

Question

def exec_command(self, command, bufsize=-1):
    #print "Executing Command: "+command
    chan = self._transport.open_session()
    chan.exec_command(command)
    stdin = chan.makefile('wb', bufsize)
    stdout = chan.makefile('rb', bufsize)
    stderr = chan.makefile_stderr('rb', bufsize)
    return stdin, stdout, stderr

在paramiko中执行命令时,它总是在运行exec_command时重置会话.我希望能够执行sudo或su,并且当我运行另一个exec_command时仍然具有这些权限.另一个例子是尝试exec_command("cd /"),然后再次运行exec_command并让它在根目录中.我知道你可以做类似exec_command("cd /; ls -l")的东西,但我需要在单独的函数调用中完成它.

Answer 1

非交互式用例

这是一个非交互式的例子......它发送cd tmp,ls然后发送exit.

import sys
sys.stderr = open('/dev/null')       # Silence silly warnings from paramiko
import paramiko as pm
sys.stderr = sys.__stderr__
import os

class AllowAllKeys(pm.MissingHostKeyPolicy):
    def missing_host_key(self, client, hostname, key):
        return

HOST = '127.0.0.1'
USER = ''
PASSWORD = ''

client = pm.SSHClient()
client.load_system_host_keys()
client.load_host_keys(os.path.expanduser('~/.ssh/known_hosts'))
client.set_missing_host_key_policy(AllowAllKeys())
client.connect(HOST, username=USER, password=PASSWORD)

channel = client.invoke_shell()
stdin = channel.makefile('wb')
stdout = channel.makefile('rb')

stdin.write('''
cd tmp
ls
exit
''')
print stdout.read()

stdout.close()
stdin.close()
client.close()

交互式用例
如果您有一个交互式用例,这个答案将无济于事......我个人会使用pexpect或exscript用于交互式会话.

Answer 2

严格来说,你不能.根据ssh规范:

会话是程序的远程执行.该程序可以是shell,应用程序,系统命令或某些内置子系统.

这意味着,一旦命令执行,会话就完成了.您无法在一个会话中执行多个命令.但是,您可以做的是启动远程shell(==一个命令),并通过stdin等与该shell进行交互...(想想执行python脚本与运行交互式解释器)

Answer 3

尝试创建由\n字符分隔的命令字符串.它对我有用.对于.例如ssh.exec_command("command_1 \n command_2 \n command_3")

Answer 4

您可以通过在客户端上调用 shell 并发送命令来完成此操作。请参考这里
该页面有 python 3.5 的代码。我对代码进行了一些修改以适用于 pythin 2.7。此处添加代码以供参考

import threading, paramiko

strdata=''
fulldata=''

class ssh:
    shell = None
    client = None
    transport = None

    def __init__(self, address, username, password):
        print("Connecting to server on ip", str(address) + ".")
        self.client = paramiko.client.SSHClient()
        self.client.set_missing_host_key_policy(paramiko.client.AutoAddPolicy())
        self.client.connect(address, username=username, password=password, look_for_keys=False)
        self.transport = paramiko.Transport((address, 22))
        self.transport.connect(username=username, password=password)

        thread = threading.Thread(target=self.process)
        thread.daemon = True
        thread.start()

    def close_connection(self):
        if(self.client != None):
            self.client.close()
            self.transport.close()

    def open_shell(self):
        self.shell = self.client.invoke_shell()

    def send_shell(self, command):
        if(self.shell):
            self.shell.send(command + "\n")
        else:
            print("Shell not opened.")

    def process(self):
        global strdata, fulldata
        while True:
            # Print data when available
            if self.shell is not None and self.shell.recv_ready():
                alldata = self.shell.recv(1024)
                while self.shell.recv_ready():
                    alldata += self.shell.recv(1024)
                strdata = strdata + str(alldata)
                fulldata = fulldata + str(alldata)
                strdata = self.print_lines(strdata) # print all received data except last line

    def print_lines(self, data):
        last_line = data
        if '\n' in data:
            lines = data.splitlines()
            for i in range(0, len(lines)-1):
                print(lines[i])
            last_line = lines[len(lines) - 1]
            if data.endswith('\n'):
                print(last_line)
                last_line = ''
        return last_line


sshUsername = "SSH USERNAME"
sshPassword = "SSH PASSWORD"
sshServer = "SSH SERVER ADDRESS"


connection = ssh(sshServer, sshUsername, sshPassword)
connection.open_shell()
connection.send_shell('cmd1')
connection.send_shell('cmd2')
connection.send_shell('cmd3')
time.sleep(10)
print(strdata)    # print the last line of received data
print('==========================')
print(fulldata)   # This contains the complete data received.
print('==========================')
connection.close_connection()