如何使用 fabric2 在本地主机上启动命令？

Question

这是我的脚本：

from fabric2 import Connection

c = Connection('127.0.0.1')
with c.cd('/home/bussiere/'):
    c.run('ls -l')

但是我有这个错误：

paramiko.ssh_exception.AuthenticationException: Authentication failed.

那么我如何运行在本地主机上执行命令？

Answer 1

在 Fabric2 中，Connection 对象有一个 local() 方法。查看此对象的文档 here.

Answer 2

截至 2020 年 7 月，对于 fabric2，如果默认情况下您不将参数传递给任务装饰器，则您位于本地计算机上。

例如，以下将运行在您的本地计算机 (localhost) 上：

示例 1：仅在本地

#python3
#fabfile.py


from fabric import task, Connection
c = Connection('remote_user@remote_server.com')


@task
def DetailList(c):
    c.run('ls -l') # will run on local server because the decorator @task does not contain the hosts parameter

然后您将运行在您的计算机上

fab DetailList

如果您想在远程服务器和本地混合使用运行ning 代码，您应该将连接作为参数传递给 @task 装饰器。

示例 2：本地和远程（但功能不同）

#python3
#fabfile.py

#imports
from fabric import task, Connection

#variables
list_of_hosts = ['user@yourserver.com'] #you should have already configure the ssh access
c = Connection(list_of_hosts[0])

working_dir = '/var/www/yourproject'

#will run on remote
@task(hosts = list_of_hosts)
def Update(c):
    c.run('sudo apt get update') # will run on remote server because hosts are passed to the task decorator
    c.run(f'cd {working_dir} && git pull') # will run on remote server because hosts are passed to the task decorator
    c.run('sudo service apache2 restart') # will run on remote server because hosts are passed to the task decorator

#will run on local because you do not specify a host
@task
def DetailsList(c):
    c.run('ls -l') # # will run on local server because hosts are NOT passed to the task decorator

正如 Ismaïl 所提到的，还有一个 'local' 方法可以在传递 hosts 参数时使用，'local' 方法将运行在本地主机上，尽管您已经指定了任务装饰器的主机参数。请注意，如果您没有指定任何主机参数，则不能使用 'local' 方法，请改用运行，如示例 1 和 2 所示。

示例 3：在远程和本地服务器上使用相同的函数，请注意，我们没有装饰在 UpdateAndRestart 函数中调用的函数。


#python3
#fabfile.py

#imports
from fabric import task, Connection

#variables
list_of_hosts = ['www.yourserver.com'] #you should have already configure the ssh access
c = Connection(list_of_hosts[0])
working_dir = '/var/www/yourproject'


def UpdateServer(c):
    c.run('sudo apt get update') # will run on remote server because hosts are passed to the task decorator
    c.local('echo the remote server is now updated') # will run on local server because you used the local method when hosts are being passed to the decorator


def PullFromGit(c):
    c.run(f'cd {working_dir} && git pull')  # will run on remote server because hosts are passed to the task decorator
    c.local('echo Git repo is now pulled')   # will run on local server because you used the local method when hosts are being passed to the decorator


def RestartServer(c):
    c.run('sudo service apache2 restart') # will run on remote server because hosts are passed to the task decorator
    c.local('echo Apache2 is now restarted') # will run on local server because you used the local method when hosts are being passed to the decorator

    
@task(hosts = list_of_hosts)
def UpdateAndRestart(c):
    UpdateServer(c)
    PullFromGit(c)
    RestartServer(c)
    c.local('echo you have updated, pulled and restarted Apache2') # will run on local server because you used the local method when hosts are being passed to the decorator

您将能够运行整个堆栈：

fab UpdateAndRestart

如何使用 fabric2 在本地主机上启动命令？

How to launch command on localhost with fabric2?

python

fabric

python-3.x