写一个python的服务监控程序
前言:
Redhat下安装Python2.7
rhel6.4自带的是2.6， 发现有的机器是python2.4。 到python站点下载源码。解压到Redhat上。然后执行以下的命令：
# ./configure --prefix=/usr/local/python27
# make
# make install
这样安装之后默认不会启用Python2.7。须要使用/usr/local/python27/bin/python2.7调用新版本号的python。
而以下的安装方式会直接接管现有的python
# ./configure
# make
# make install
開始：服务子进程被监控主进程创建并监控，当子进程异常关闭，主进程能够再次启动之。使用了python的subprocess模块。就这个简单的代码，竟然互联网上没有现成可用的样例。
没办法。我写好了贡献出来吧。
首先是主进程代码：service_mgr.py
#!/usr/bin/python#-*- coding: UTF-8 -*-# cheungmine# stdin、stdout和stderr分别表示子程序的标准输入、标准输出和标准错误。# # 可选的值有:# subprocess.PIPE - 表示须要创建一个新的管道.# 一个有效的文件描写叙述符（事实上是个正整数）# 一个文件对象# None - 不会做不论什么重定向工作。子进程的文件描写叙述符会继承父进程的.# # stderr的值还能够是STDOUT, 表示子进程的标准错误也输出到标准输出.# # subprocess.PIPE# 一个能够被用于Popen的stdin、stdout和stderr 3个參数的特输值，表示须要创建一个新的管道.# # subprocess.STDOUT# 一个能够被用于Popen的stderr參数的特输值。表示子程序的标准错误汇合到标准输出.################################################################################import osimport sysimport getoptimport timeimport datetimeimport codecsimport optparseimport ConfigParserimport signalimport subprocessimport select# logging# require python2.6.6 and laterimport logging from logging.handlers import RotatingFileHandler## log settings: SHOULD BE CONFIGURED BY configLOG_PATH_FILE = "./my_service_mgr.log"LOG_MODE = 'a'LOG_MAX_SIZE = 4*1024*1024 # 4M per fileLOG_MAX_FILES = 4 # 4 Files: my_service_mgr.log.1, printmy_service_mgrlog.2, ... LOG_LEVEL = logging.DEBUG LOG_FORMAT = "%(asctime)s %(levelname)-10s[%(filename)s:%(lineno)d(%(funcName)s)] %(message)s" handler = RotatingFileHandler(LOG_PATH_FILE, LOG_MODE, LOG_MAX_SIZE, LOG_MAX_FILES)formatter = logging.Formatter(LOG_FORMAT)handler.setFormatter(formatter)Logger = logging.getLogger()Logger.setLevel(LOG_LEVEL)Logger.addHandler(handler) # color output#pid = os.getpid() def print_error(s): print '\033[31m[%d: ERROR] %s\033[31;m' % (pid, s)def print_info(s): print '\033[32m[%d: INFO] %s\033[32;m' % (pid, s)def print_warning(s): print '\033[33m[%d: WARNING] %s\033[33;m' % (pid, s)def start_child_proc(command, merged): try: if command is None: raise OSError, "Invalid command" child = None if merged is True: # merge stdout and stderr child = subprocess.Popen(command, stderr=subprocess.STDOUT, # 表示子进程的标准错误也输出到标准输出 stdout=subprocess.PIPE # 表示须要创建一个新的管道 ) else: # DO NOT merge stdout and stderr child = subprocess.Popen(command, stderr=subprocess.PIPE, stdout=subprocess.PIPE) return child except subprocess.CalledProcessError: pass # handle errors in the called executable except OSError: pass # executable not found raise OSError, "Failed to run command!"def run_forever(command): print_info("start child process with command: " + ' '.join(command)) Logger.info("start child process with command: " + ' '.join(command)) merged = False child = start_child_proc(command, merged) line = '' errln = '' failover = 0 while True: while child.poll() != None: failover = failover + 1 print_warning("child process shutdown with return code: " + str(child.returncode)) Logger.critical("child process shutdown with return code: " + str(child.returncode)) print_warning("restart child process again, times=%d" % failover) Logger.info("restart child process again, times=%d" % failover) child = start_child_proc(command, merged) # read child process stdout and log it ch = child.stdout.read(1) if ch != '' and ch != '\n': line += ch if ch == '\n': print_info(line) line = '' if merged is not True: # read child process stderr and log it ch = child.stderr.read(1) if ch != '' and ch != '\n': errln += ch if ch == '\n': Logger.info(errln) print_error(errln) errln = '' Logger.exception("!!!should never run to this!!!") if __name__ == "__main__": run_forever(["python", "./testpipe.py"]) 然后是子进程代码：testpipe.py #!/usr/bin/python#-*- coding: UTF-8 -*-# cheungmine# 模拟一个woker进程,10秒挂掉import osimport sysimport timeimport randomcnt = 10while cnt >= 0: time.sleep(0.5) sys.stdout.write("OUT: %s\n" % str(random.randint(1, 100000))) sys.stdout.flush() time.sleep(0.5) sys.stderr.write("ERR: %s\n" % str(random.randint(1, 100000))) sys.stderr.flush() #print str(cnt) #sys.stdout.flush() cnt = cnt - 1sys.exit(-1) Linux上执行非常easy： $ python service_mgr.py
Windows上以后台进程执行：
> start pythonw service_mgr.py
代码中须要改动：
run_forever(["python", "testpipe.py"])