python - Paramiko recv_ready() 返回假值

Question

我尝试使用 paramiko 远程执行多个命令，但是 recv_ready() 未返回正确的值。
例如，在执行pwd\n命令之后，它将连续报告 channel 尚未准备好(显然是错误的)。对于某些命令它可以正常工作，例如ls。我正在做的事情有问题吗，或者 paramiko 有问题吗？

import paramiko
import re
import time

def sudo_ssh(hostname, usernameIn, passIn, cmd):

    # Create an SSH client
    client = paramiko.SSHClient()

    # Make sure that we add the remote server's SSH key automatically
    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())

    # Connect to the client
    client.connect(hostname, username=usernameIn, password=passIn)

    # Create a raw shell
    channel = client.invoke_shell()


    # Send the sudo command
    for command in cmd:
        print("CMD= " + command + "\n")
        time.sleep(1)

        # wait until channel is ready
        while not channel.recv_ready() :
            print("NOT READY " + str(channel.recv_ready()) + "\n \n")
            time.sleep(1)

        # Send the command
        channel.send(command)
        channel.send("\n")

        # Wait a bit, if necessary
        time.sleep(1)

        # Flush the receive buffer
        receive_buffer = channel.recv(4096)

        # If promted send the sudo pass
        if re.search(b".*\[sudo\].*", receive_buffer): 
            time.sleep(1)
            print(" TYPING SUDO PASSWORD .... \n")
            channel.send( "sudoPass" + "\n" )
            receive_buffer = channel.recv(4096)

        # Print the receive buffer, if necessary
        print(receive_buffer)

    print("Executed all of the commands. Now will exit \n")
    client.close()


com = []
com.append("sudo ls")
com.append("cd /home/user/Downloads")
com.append("sleep 5")
com.append("ls")
com.append("pwd")
com.append("cd /opt/")
sudo_ssh("myhost.com", "user", "pass", com)

Answer 1

recv_ready方法是检查 channel 的数据是否准备好读取，即数据是否被缓冲。它不会检查 channel 本身是否已准备好，请参阅 - recv_ready() .

所以你应该移动 recv_ready() while 循环就在 receive_buffer = channel.recv(4096) 之前使其发挥作用。