Python的自动化部署模块Fabric的安装及使用指南

fabric是python2.5或者更高的库,可以通过ssh在多个host上批量执行任务.完成系统管理任务.它提供一套基本操作在本地和远程执行shell命令,或者上传下载文件,辅助提供用户输入或终止执行.

下面安装fabric模块有2种方法:

1.使用easy_install(下面是debain5环境)

    root@10.1.6.200:pshell# apt-get install python-dev (安装Python头文件)

    root@10.1.6.200:pshell# apt-get install python-setuptools (安装easy_install)

    root@10.1.6.200:pshell# wget http://peak.telecommunity.com/dist/ez_setup.py

    root@10.1.6.200:pshell# python ez_setup.py

    root@10.1.6.200:pshell# easy_install fabric

    Searching for fabric
    Reading http://pypi.python.org/simple/fabric/
    Best match: Fabric 1.6.1
    Downloading http://pypi.python.org/packages/source/F/Fabric/Fabric-1.6.1.tar.gz#md5=c318ac3f7011ede0be1ca9a20f435735
    Processing Fabric-1.6.1.tar.gz
    Running Fabric-1.6.1/setup.py -q bdist_egg --dist-dir /tmp/easy_install-CVuLrs/Fabric-1.6.1/egg-dist-tmp-ZFNoWY
    warning: no previously-included files matching '*' found under directory 'docs/_build'
    warning: no previously-included files matching '*.pyc' found under directory 'tests'
    warning: no previously-included files matching '*.pyo' found under directory 'tests'
    zip_safe flag not set; analyzing archive contents...
    fabric.version: module references __file__
    Adding Fabric 1.6.1 to easy-install.pth file
    Installing fab script to /usr/bin
    ....
    Installed /usr/lib/python2.5/site-packages/pycrypto-2.6-py2.5-linux-x86_64.egg
    Finished processing dependencies for fabric

2.使用pip(下面使用的是debian7环境)

    apt-get install python-pip
    pip install fabric
    apt-get install python-paramiko

导入模块未报错说明安装成功.

实例:

1.在调用fabric的时候使用命令行参数,-H 指定哪台主机

    root@10.1.6.201:python# cat fabfile4.py 

    #!/usr/bin/env python
    #coding=utf-8
    from fabric.api import *

    def printMem():
       cmd_output = run('free -m')
       print cmd_output

    root@10.1.6.201:python# fab -H root@10.1.1.45 printMem -f fabfile4.py
    [root@10.1.1.45] Executing task 'printMem'
    [root@10.1.1.45] run: free -m
    [root@10.1.1.45] Login password for 'root': #提示输入密码
    [root@10.1.1.45] out:       total    used    free   shared  buffers   cached
    [root@10.1.1.45] out: Mem:     1005    968     37     0     36    831
    [root@10.1.1.45] out: -/+ buffers/cache:    100    904
    [root@10.1.1.45] out: Swap:     1913     0    1913
    [root@10.1.1.45] out: 

    total    used    free   shared  buffers   cached
    Mem:     1005    968     37     0     36    831
    -/+ buffers/cache:    100    904
    Swap:     1913     0    1913

    Done.
    Disconnecting from 10.1.1.45:22000... done.

2.以上我们需要输入密码才能完成操作,怎样自动执行呢?可以在fabfile4文件中配置HOST.也就是环境变量.

    root@10.1.6.201:python# vim fabfile.py

    #!/usr/bin/env python
    #coding=utf-8
    from fabric.api import *
    from fabric.context_managers import *

    env.host_string = '10.1.1.45'
    env.port = '22000'       #默认端口22,默认登录用户root
    env.password='passwd'

    def test1():
      with cd('/home'):
        run('ls -l')

    test1()

    root@10.1.6.201:python# python fabfile.py  #脚本执行

    [10.1.1.45] run: ls -l
    [10.1.1.45] out: total 8
    [10.1.1.45] out: drwxr-xr-x 2 debian debian 4096 2012-08-27 11:54 debian
    [10.1.1.45] out: drwxr-xr-x 2 root  nogroup 4096 2013-05-22 18:07 ftp
    [10.1.1.45] out:

    root@10.1.6.201:python# vim fabfile1.py

    #!/usr/bin/env python
    #coding=utf-8
    from fabric.api import *
    from fabric.context_managers import *

    env.hosts = ['10.1.6.200','10.1.1.45']
    env.port = '22000'
    env.password='passwd'

    def test1():
      with cd('/home'): #更改目录
        run('ls -l')

    root@10.1.6.201:python# fab test1 -f fabfile.py #使用fab指定任务执行,注意文件后默认跟fabfile.py

    [10.1.6.200] Executing task 'test1'
    [10.1.6.200] run: ls -l
    [10.1.6.200] out: total 24
    [10.1.6.200] out: drwxr-xr-x 2 davehe davehe 4096 2013-02-27 10:00 davehe
    [10.1.6.200] out: -rw-r--r-- 1 root  root  1990 2013-02-27 09:55 davehe.tar.gz
    [10.1.6.200] out: -rw-r--r-- 1 root  root  396 2013-05-17 18:27 rsync_log_130517
    [10.1.6.200] out: -rw-r--r-- 1 root  root  7916 2013-05-20 21:04 rsync_log_130520
    [10.1.6.200] out: drwxr-xr-x 2 taomee taomee 4096 2013-01-29 04:27 taomee
    [10.1.6.200] out: 

    [10.1.1.45] Executing task 'test1'
    [10.1.1.45] run: ls -l
    [10.1.1.45] out: total 8
    [10.1.1.45] out: drwxr-xr-x 2 debian debian 4096 2012-08-27 11:54 debian
    [10.1.1.45] out: drwxr-xr-x 2 root  nogroup 4096 2013-05-22 18:07 ftp
    [10.1.1.45] out: 


    Done.
    Disconnecting from 10.1.1.45:22000... done.
    Disconnecting from 10.1.6.200:22000... done.

3.使用get/put.利用sftp协议上传下载文件

    root@10.1.6.201:python# cat fabfile1.py

    #!/usr/bin/env python
    #coding=utf-8
    from fabric.api import *
    from fabric.colors import *
    from fabric.context_managers import *

    env.hosts = ['10.1.1.45']
    env.port = '22000'
    env.password='passwd'

    def test1():
      print(red("i'm 201"))
      local('ls -l /tmp')

    def test2():
      print (green("i'm get file 45 to 186"))
      get('/home/ftp/a.txt','/tmp/') #下载
    #  put('/tmp/','/home/ftp/') #上传
      local('ls -l /tmp')  #local运行本地命令


    def final():
      execute(test1)
      execute(test2)

    root@10.1.6.201:python# fab final -f fabfile1.py

    [10.1.1.45] Executing task 'final'
    [10.1.1.45] Executing task 'test1'
    i'm 201
    [localhost] local: ls -l /tmp
    total 31684
    drwxr-xr-x 2 root root   4096 May 13 22:08 bin
    drwxr-xr-x 3 root root   4096 May 13 22:08 conf
    drwxr-xr-x 6 root root   4096 May 13 22:08 etc
    -rwxr-xr-x 1 root root   6797 May 13 22:08 init
    -rw-r--r-- 1 root root 32400896 May 13 22:07 initrd.img-3.2.0-4-amd64
    drwxr-xr-x 6 root root   4096 May 13 22:08 lib
    drwxr-xr-x 2 root root   4096 May 13 22:08 lib64
    drwxr-xr-x 2 root root   4096 May 13 22:08 run
    drwxr-xr-x 2 root root   4096 May 13 22:08 sbin
    drwxr-xr-x 6 root root   4096 May 13 22:08 scripts
    [10.1.1.45] Executing task 'test2'
    i'm get file 45 to 186
    [10.1.1.45] download: /tmp/a.txt <- /home/ftp/a.txt
    [localhost] local: ls -l /tmp
    total 31688
    -rw-r--r-- 1 root root    6 May 29 22:29 a.txt
    drwxr-xr-x 2 root root   4096 May 13 22:08 bin
    drwxr-xr-x 3 root root   4096 May 13 22:08 conf
    drwxr-xr-x 6 root root   4096 May 13 22:08 etc
    -rwxr-xr-x 1 root root   6797 May 13 22:08 init
    -rw-r--r-- 1 root root 32400896 May 13 22:07 initrd.img-3.2.0-4-amd64
    drwxr-xr-x 6 root root   4096 May 13 22:08 lib
    drwxr-xr-x 2 root root   4096 May 13 22:08 lib64
    drwxr-xr-x 2 root root   4096 May 13 22:08 run
    drwxr-xr-x 2 root root   4096 May 13 22:08 sbin
    drwxr-xr-x 6 root root   4096 May 13 22:08 scripts

    Done.
    Disconnecting from 10.1.1.45:22000... done.

上面实例中只列举了几个常用的farbic环境变量.如env.hosts,env.password等,可以不需要交互输入密码.

以下还有常用环境变量以供参考:

• exclude_hosts:指定一个主机列表，在fab执行时，忽略列表中的机器
• user:ssh使用哪个用户登录远程主机
• hosts :全局的host列表
• host_string :当fabric连接远程机器执行run、put时，设置的user/host/port等
• password:默认ssh连接远程主机密码,也可以是sudo提示输入密码
• password:一个字典供内部使用,为每台主机host设置密码,key是主机,value值存放密码
• port:设置默认端口
• roledefs:使用字典定义角色名字对应的主机ip
• roles:一个全局的role列表

    from fabric.api import run, roles

    env.roledefs = {
      'db': ['db1', 'db2'],
      'web': ['web1', 'web2', 'web3'],
    }

    @roles('db')
    def migrate():
      # Database stuff here.
      pass

    @roles('web')
    def update():
      # Code updates here.
      pass

fab也可以使用命令设置环境变量,常用命令

• -f FABFILE, --fabfile=FABFILE 默认fabfile.py
• -H HOSTS, --hosts=HOSTS env.hosts=hosts
• -p PASSWORD, --password=PASSWORD env.password
• -R ROLES, --roles=ROLES env.roles