Python Fabric 任务可以调用其他任务并尊重其主机列表吗？

Question

我有一个如下所示的 fabfile：

@hosts('host1')
def host1_deploy():
    """Some logic that is specific to deploying to host1"""

@hosts('host2')
def host2_deploy():
    """Some logic that is specific to deploying to host2"""

def deploy():
    """"Deploy to both hosts, each using its own logic"""
    host1_deploy()
    host2_deploy()

我想做

fab deploy

并让它相当于

fab host1_deploy host2_deploy

换句话说，运行每个子任务，并为每个子任务使用它指定的主机列表。然而，这是行不通的。相反，deploy() 任务需要自己的主机列表，并将其传播到其所有子任务。

有没有办法在这里更新部署（）任务，以便它可以做我想要的事情，同时保留子任务，以便它们可以单独运行？

Answer 1

从 Fabric 1.3 开始，execute 助手现在可以用来执行此操作。该文档位于此处：智能执行执行任务。

这是他们使用的示例：

from fabric.api import run, roles, execute

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

然后从另一个任务deploy运行migrate和web：

def deploy():
    execute(migrate)
    execute(update)

这将尊重角色和主机列表这些任务有。

Answer 2

这是蹩脚的，但它从 Fabric 1.1.2 开始工作，

def host1_deploy():
    """Some logic that is specific to deploying to host1"""
    if env.host in ["host1"]:
        pass #this is only on host2

def host2_deploy():
    """Some logic that is specific to deploying to host2"""
    if env.host in ["host2"]:
        pass #this is only on host2

def deploy():
    """"Deploy to both hosts, each using its own logic"""
    host1_deploy()
    host2_deploy()

这是我的测试代码：

@task
@roles(["prod_web","prod_workers"])
def test_multi():
    test_multi_a()
    test_multi_b()

def test_multi_a():
    if env.host in env.roledefs["prod_web"]:
        run('uname -a')

def test_multi_b():
    if env.host in env.roledefs["prod_workers"]:
        run('uname -a')

Answer 3

可能有更好的方法来处理它，但是您可以将两个主机传递给deploy()，然后在host1_deploy()和host2_deploy()中检查env.host：

def host1_deploy():
    if env.host in ['host1']:
         run(whatever1)

def host2_deploy():
    if env.host in ['host2']:
         run(whatever2)

@hosts('host1','host2')
def deploy():
    host1_deploy()
    host2_deploy()

Answer 4

试试这个。显然您想用 run 或 sudo 替换 local。关键是用于 deploy 的空 @hosts 装饰器

from fabric.api import local
from fabric.decorators import hosts

@hosts('host1')
def host1_deploy():
    """Some logic that is specific to deploying to host1"""
    local('echo foo')

@hosts('host2')
def host2_deploy():
    """Some logic that is specific to deploying to host2"""
    local('echo bar')

@hosts('')
def deploy():
    """"Deploy to both hosts, each using its own logic"""
    host1_deploy()
    host2_deploy()