Python从telnetlib输出获取IP地址

Question

使用telnetlib我从我的路由器中获取路由信息，并且想要使用模式提取WAN IP地址。 telnet会话的输出位于一个变量中，行之间用\ n分隔。

来自telnet会话的东西。

l= tn.read_all() 
>>> l 
'\r\nip -f inet addr\r\nexit\r\nadmin4asus@RT-AC68U:/tmp/home/root# ip -f inet addr\r\n1: lo: <LOOPBACK,MULTICAST,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN \r\n inet 127.0.0.1/8 brd 127.255.255.255 scope host lo\r\n2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000\r\n inet 24.6.29.214/21 brd 24.6.31.255 scope global eth0\r\n7: br0: <BROADCAST,MULTICAST,ALLMULTI,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN \r\n inet 192.168.11.1/24 brd 192.168.11.255 scope global br0\r\n8: tun21: <POINTOPOINT,MULTICAST,NOARP,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 100\r\n inet 10.8.0.1 peer 10.8.0.2/32 scope global tun21\r\nadmin4asus@RT-AC68U:/tmp/home/root# exit\r\n' 
>>> 

现在我的代码。

l= tn.read_all() 
for line in l.split('\n'): 
    match= re.findall(r'([0-9]+(?:\.[0-9]+){3}).*scope global eth0', line) 
    if match is not None: 
     print('Found ' + line) 

我本来料想到一行符合打印。

Found  inet 24.6.29.214/21 brd 24.6.31.255 scope global eth0 

但我得到无处不在。

Found 
Found ip -f inet addr 
Found exit 
Found admin4asus@RT-AC68U:/tmp/home/root# ip -f inet addr 
Found 1: lo: <LOOPBACK,MULTICAST,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
Found  inet 127.0.0.1/8 brd 127.255.255.255 scope host lo 
Found 2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000 
Found  inet 24.6.29.214/21 brd 24.6.31.255 scope global eth0 
Found 7: br0: <BROADCAST,MULTICAST,ALLMULTI,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN 
Found  inet 192.168.11.1/24 brd 192.168.11.255 scope global br0 
Found 8: tun21: <POINTOPOINT,MULTICAST,NOARP,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 100 
Found  inet 10.8.0.1 peer 10.8.0.2/32 scope global tun21 
Found admin4asus@RT-AC68U:/tmp/home/root# exit 
Found 

我找不出为什么我的代码失败。如果专家有一个更好的方法（解释），那会很好。

编辑：

扬的回答肯定是更Python，但我缺乏蟒蛇的知识让我更喜欢VKS这是容易理解我。我给了两个'^'，并将vks标记为首选（在“我偏好的意义上”）。

我最终在'split'cmd和下面的代码中使用'\ r \ n'。

def get_asus_wan_ip(): 
    "Gets WAN IP from ASUS router" 

    import telnetlib 
    import re 

    ASUS_IP= '192.168.1.1' 
    ASUS_USER= 'xxxxxxxx' 
    ASUS_PASS= 'yyyyyyyy' 
    tn = telnetlib.Telnet(ASUS_IP) 

    tn.read_until("login: ") 
    tn.write(ASUS_USER + "\n") 
    tn.read_until("Password: ") 
    tn.write(ASUS_PASS + "\n") 
    tn.write("ifconfig eth0\n") 
    tn.write("exit\n") 
    l= tn.read_all() 
    for line in l.split('\r\n'): 
     match= re.findall(r'^\s+inet addr:([0-9]+(?:\.[0-9]+){3}).*', line) 
     if match: 
      break 

    wan_ip= match[0] 
    return wan_ip 

Answer 1

import re 
x="""'\r\nip -f inet addr\r\nexit\r\nadmin4asus@RT-AC68U:/tmp/home/root# ip -f inet addr\r\n1: lo: <LOOPBACK,MULTICAST,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN \r\n inet 127.0.0.1/8 brd 127.255.255.255 scope host lo\r\n2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000\r\n inet 24.6.29.214/21 brd 24.6.31.255 scope global eth0\r\n7: br0: <BROADCAST,MULTICAST,ALLMULTI,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN \r\n inet 192.168.11.1/24 brd 192.168.11.255 scope global br0\r\n8: tun21: <POINTOPOINT,MULTICAST,NOARP,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 100\r\n inet 10.8.0.1 peer 10.8.0.2/32 scope global tun21\r\nadmin4asus@RT-AC68U:/tmp/home/root# exit\r\n'""" 
for line in x.split('\n'): 
    match= re.findall(r'(?:[0-9]+(?:\.[0-9]+){3}).*scope global eth0', line) 
    if match: 
     print('Found ' + line) 

输出：Found inet 24.6.29.214/21 brd 24.6.31.255 scope global eth0

个问题与您的代码：

1）re.findall回报list，所以它不可能是None它可以empty.So使用，在if条件。

2）re.findall只返回组，如果有一些。如果你想整行，使第一组不捕获。

Answer 2

您可以大大与列表理解收缩代码：

import re 

string = """ 
1: lo: <LOOPBACK,MULTICAST,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN 
    inet 127.0.0.1/8 brd 127.255.255.255 scope host lo 
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000 
    inet 24.6.29.214/21 brd 24.6.31.255 scope global eth0 
7: br0: <BROADCAST,MULTICAST,ALLMULTI,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN 
    inet 192.168.11.1/24 brd 192.168.11.255 scope global br0 
8: tun21: <POINTOPOINT,MULTICAST,NOARP,PROMISC,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 100 
    inet 10.8.0.1 peer 10.8.0.2/32 scope global tun21 
""" 

rx = re.compile(r'\b(\d+(?:\.\d+){3})\b.*scope global eth0') 
matches = [line 
      for line in string.split("\n") 
      for match in [rx.search(line)] 
      if match] 
print(matches) 
# [' inet 24.6.29.214/21 brd 24.6.31.255 scope global eth0'] 

或者如果你喜欢filter()和lambda()：

matches = list(filter(lambda x: rx.search(x), string.split("\n"))) 
print(matches)