memcached启动脚本（class练习）

说明：使用类的方式编写程序启动脚本（memcached)
 1 import time
 2 import os
 3 from subprocess import Popen,PIPE
 4 
 5 class Process(object):
 6     'mamcached rc scripts'
 7     def __init__(self,name,program,args,workdir):
 8         self.name = name
 9         self.program = program
10         self.args = args
11         self.workdir = workdir
12         self._init()
13 
14     def _init(self):
15         '''/var/tmp/memcached'''
16         if not os.path.exists(self.workdir):
17             os.mkdir(self.workdir)
18             os.chdir(self.workdir)
19 
20     def _pidfile(self):
21         '''/var/tmp/memcached/memcached.pid'''
22         return os.path.join(self.workdir,'%s.pid' % self.name)
23 
24     def _writepid(self):
25         if self.pid:
26             with open(self._pidfile(),'w') as fd:
27                 fd.write(str(self.pid))
28 
29     def _getpid(self):
30         p = Popen(['pidof','memcached'],stdout=PIPE)
31         pid = p.stdout.read().strip('
')
32         if pid:
33             return int(pid)
34         return None
35 
36     def start(self):
37         cmd = self.program + ' ' + self.args
38         p = Popen(cmd,stdout=PIPE,shell=True)
39         self.pid = p.pid
40         self._writepid()
41         print('%s start Successful ' % self.name)
42 
43     def stop(self):
44         result = self._getpid()
45         if result:
46             os.kill(result,15)
47             if os.path.exists(self._pidfile()):
48                 os.remove(self._pidfile())
49             print('The %s are stoped !' % self.name)
50 
51     def restart(self):
52         self.stop()
53         time.sleep(1)
54         self.start()
55 
56     def status(self):
57         pid = self._getpid()
58         if pid:
59             print('The %s is running , The pid is %s' % (self.name,pid))
60         else:
61             print('The %s is not running!' % self.name)
62 
63     def help(self):
64         print('Usage: %s {start|restart|status|stop}' % __file__ )
65 
66 def main():
67     name = 'memcached'
68     program = '/usr/bin/memcached'
69     args = '-u nobody -p 11211 -c 1024 -m 64 '
70     wd = '/var/tmp/memcached'
71     pm = Process(name,program,args,wd)
72     try:
73         cmd = sys.argv[1]
74     except IndexError as e:
75         sys.exit('Option Error')
76     if cmd == 'start':
77         pm.start()
78     elif cmd == 'stop':
79         pm.stop()
80     elif cmd == 'restart':
81         pm.restart()
82     elif cmd == 'status':
83         pm.status()
84     else:
85         pm.help()
86 
87 
88 if __name__ == '__main__':
89     main()