如何使用函数来填充for循环中的变量？

Question

我是一个Python和开发人员的完整新手，我被困在一个项目中。

我有一个函数可以从我的Salt Master中获取服务器列表。然后，我尝试在for循环中使用该列表来连接到该服务器并将我的公钥复制到它们。当我硬编码服务器运行没有问题。它看起来像我的for循环中的变量不返回任何东西。

这是我的For循环。

def deploy_key(key, server, username, password): 
    ssh = paramiko.SSHClient() 
    ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) 
    ssh.connect(server, username=username, password=password) 
    transport = ssh.get_transport() 
    session = transport.open_session() 
    session.set_combine_stderr(True) 
    session.get_pty() 
    session = transport.open_session() 
    session.set_combine_stderr(True) 
    session.get_pty() 
    for commands in l_commands: 
     session = transport.open_session() 
     session.set_combine_stderr(True) 
     session.get_pty() 
     session.exec_command(commands) 
     stdin = session.makefile('wb', -1) 
     stdout = session.makefile('rb', -1) 
     stdin.write(password + '\n') 
     stdin.flush() 

username = "myUserName" 
password = "myPassword" 
server = hosts() 
user = getUser() 
key = getKey() 
l_commands = ['sudo mkdir -p /home/%s/.ssh/' % user,'sudo chmod -R 777 /home/%s' %user, 
      'sudo echo "%s" >> /home/%s/.ssh/authorized_keys' %(key, user), 
      'sudo chmod 644 /home/%s/.ssh/authorized_keys' % user, 
      'sudo chmod 700 /home/%s/.ssh/' % user, 'sudo chmod 755 /home/%s' %user] 

for host in server: 
    deploy_key(key, host, username, password) 

这里是我的函数来获取变量

import paramiko 

l_password = "myPassword" 
l_host = "saltMaster.salt.com" 
l_commands = "sudo salt-key -L" 
l_user = "myUser" 

def hosts(): 
    ssh = paramiko.SSHClient() 
    ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) 
    ssh.connect(l_host, username=l_user, password=l_password) 
    transport = ssh.get_transport() 
    session = transport.open_session() 
    session.set_combine_stderr(True) 
    session.get_pty() 
    session = transport.open_session() 
    session.set_combine_stderr(True) 
    session.get_pty() 
    session.exec_command(l_commands) 
    stdin = session.makefile('wb', -1) 
    stdout = session.makefile('rb', -1) 
    stdin.write(l_password + '\n') 
    stdin.flush() 

    for line in stdout.read().splitlines(): 
     input_line = line 
     input_line = input_line.replace(b"\x1b[0;32m", b'') # remove \x1b[1;32m 
     input_line = input_line.replace(b"\x1b[0;0m", b'') # remove \x1b[1;35m 
     input_line = input_line.replace(b"\x1b[0;1;34mRejected Keys:", b'') # remove \x1b[1;36m 
     input_line = input_line.replace(b"\x1b[0;1;31mUnaccepted Keys:", b'') # remove \x1b[1m 
     input_line = input_line.replace(b"\x1b[0;1;35mDenied Keys:", b'') # remove \x07 (BEL) 
     input_line = input_line.replace(b"\x1b[0;1;32mAccepted Keys:", b'') # remove \x07 (BEL) 
     input_line = input_line.replace(b"Freedom1", b'') # remove \x07 (BEL) 

     hostsIndividual = str(input_line,"utf-8") 
     return(hostsIndividual) 

Answer 1

的问题是在hosts()方法的return语句。

def hosts(): 
    // your code goes here 

    for line in stdout.read().splitlines(): 
     // your code goes here 
     hostsIndividual = str(input_line,"utf-8") 
     return(hostsIndividual) 

这里循环将只运行一次作为功能将在循环的第一个迭代返回单个String。你应该首先在循环之外放置返回语句。

def hosts(): 
    // your code goes here 

    for line in stdout.read().splitlines(): 
     // your code goes here 
     hostsIndividual = str(input_line,"utf-8") 

    return(hostsIndividual) // returning only one host name 

你还需要使用服务器名称（串）的list和hosts()方法，而只返回hostIndividual（一个String）返回它，如下所示。

def hosts(): 
    // your code goes here 

    hosts = [] 
    for line in stdout.read().splitlines(): 
     // your code goes here 
     hostsIndividual = str(input_line,"utf-8") 
     hosts.append(hostsIndividual) 

    return(hosts) // now returning a list of host name 

现在您可以遍历hosts()返回的服务器列表（字符串列表）。

for host in server: 
    deploy_key(key, host, username, password) 

Answer 2

您的循环返回单个字符串，即您找到的第一个输入行。 因此，在你的主程序，服务器是一家单一的字符串，你的循环

for host in server: 

遍历该字符串的字符。试着做此更改你的函数的循环...而不是

for line in ... 
    ... 
    hostsIndividual = str(input_line,"utf-8") 
    return(hostsIndividual) 

使用

server_list = [] 
for line in ... 
    ... 
    hostsIndividual = str(input_line,"utf-8") 
    server_list.append(hostsIndividual) 

return(server_list) 

这将构建串，每一个都是一个服务器的列表; 循环完成后，它将整个列表返回给主程序。