用Python写运维脚本时，经常需要执行linux shell的命令，Python中的commands模块专门用于调用Linux shell命令，并返回状态和结果，下面是commands模块的3个主要函数：
1. commands.getoutput('shell command')
执行shell命令，返回结果（string类型）
>>> commands.getoutput('pwd') '/home/oracle'
2. commands.getstatusoutput('shell command')
执行shell命令, 返回两个元素的元组tuple(status, result)，status为int类型，result为string类型。
cmd的执行方式是{ cmd ; } 2>&1, 故返回结果包含标准输出和标准错误.
>>> commands.getstatusoutput('pwd') (0, '/home/oracle') 下面的一个脚本利用commands模块检测磁盘使用率，标识出大于10%的磁盘（百分比可根据实际情况调整，一般设为90%，本例为了更好的说明情况，设为10%）：
import commands threshold = 10 flag = False title=commands.getoutput("df -h|head -1") ''''' Check sda disk space usage like below format: /dev/sda2 20G 2.3G 17G 13% / /dev/sda6 20G 306M 19G 2% /var /dev/sda3 49G 2.8G 44G 7% /home /dev/sda5 49G 4.5G 42G 10% /opt /dev/sda1 194M 12M 172M 7% /boot ''' chkDiskList=commands.getoutput("df -h|grep sda").split('\n') usedPercents=commands.getoutput("df -h|grep sda|awk '{print $5}'|grep -Eo '[0-9]+'").split('\n') for i in range(0,len(usedPercents)): if int(usedPercents[i]) >= threshold: chkDiskList[i] += ' ----Caution!!! space usage >= ' + str(threshold) flag = True ''''' Check disk space usage like below format: /dev/mapper/backup-backup_lv 751G 14G 699G 2% /backup /dev/mapper/data-data_lv 751G 172G 540G 25% /data ''' chkDiskList_2=commands.getoutput("df -h|grep -v sda|grep -v tmp|grep -v system").split('\n') usedPercents_2=commands.getoutput("df -h|grep -v map|grep -v sda|grep -v tmp|grep -v system|awk '{print $4}'|grep -Eo '[0-9]+'").split('\n') for i in range(0,len(usedPercents_2)): if int(usedPercents_2[i]) >= threshold: chkDiskList_2[i*2 + 1] += ' ----Caution!!! space usage >= ' + str(threshold) flag = True if flag == True: #combine tile, chkDiskList, chkDisklist_2 result = [title,] result.extend(chkDiskList) result.extend(chkDiskList_2) for line in result: print line
# !/usr/bin/env python# -*- coding: utf-8 -*import osimport commandsimport sysimport jsondef main(): mode = sys.argv[1] if len(sys.argv) >= 2 else 'post' url = "http://127.0.0.1:5004/" if mode == 'post': body_value = "{'geo':{'lat':120.0,'lat':20.0}, 'devicetype':4,'osv':'3.1.2', 'w':1920, 'h':1280, 'orientation':1,'user':{'id':'321','yob':1990}}" cmd = 'curl -l -H "Content-type: application/json" -X POST -d \'{"phone":"13521389587","password":"test","geo":{"lat":120,"lat":20}}\' http://127.0.0.1:5004/' else: cmd = 'curl -v "%s"' % (url) status, ouput = commands.getstatusoutput(cmd) s = ('success' if status == 0 else 'fail') + '\n\n\n---->\n\n\n\n' + ouput + '\n\n\n' print s exit(0)if __name__ == '__main__': main()