limit.py

# coding:utf-8
import sys, time, os,urllib,re



def get_net_data(interface):
  for line in open('/proc/net/dev', 'r'):
    if line.split(':')[0].find(interface)>=0:
      return map(int, line.split(':')[1].split())


def stop_limit():
  os.system('sudo /sbin/tc qdisc dele dev eth0 root')
  return 'cancaled'
def start_limit ():
  os.system('/sbin/tc qdisc add dev eth0 root handle 1: htb default 25')
  os.system('/sbin/tc class add dev eth0 parent 1: classid 1:1 htb rate 500kbps')
  os.system('/sbin/tc qdisc add dev eth0 parent 1:1 netem delay 20ms 0ms')
  os.system('/sbin/tc filter add dev eth0 parent 1: protocol ip prio 1 u32 match ip dst 0.0.0.0/0 flowid 1:1')
  return 'apply'
  


  '''
  /sbin/tc qdisc add dev eth0 root handle 1: htb default 25
  /sbin/tc class add dev eth0 parent 1: classid 1:1 htb rate 200kbps
  /sbin/tc qdisc add dev eth0 parent 1:1 netem delay 20ms 0ms
  /sbin/tc filter add dev eth0 parent 1: protocol ip prio 1 u32 match ip dst 0.0.0.0/0 flowid 1:1
  /sbin/tc qdisc dele dev eth0 root
  '''
def Get_net():
  interface = 'eth0'
  net_data = get_net_data(interface)
  #receive = int(net_data[0])/ 1048576 #接受总流量
  transmit = int(net_data[8]) / 1048576#发送总流量
  return transmit

if __name__ == '__main__':
  ago_transmit = Get_net()
  now_time = ago_time = time.time()
  stats = stop_limit()
  bool = True
  while bool:
    transmit = Get_net()
    now_time = time.time()
    df_tx = transmit - ago_transmit
    df_tm = now_time - ago_time
    now_time = time.time()
    if  df_tx >= 7:
      stats = start_limit()
      ago_transmit = transmit
    else:
      ago_transmit = transmit 


    if  df_tm >=30:
      stats = stop_limit()
      ago_time = now_time
    #bool = False
    time.sleep(1)