fab.md

Using fabric for Automating Remote Tasks

To automate deployment tasks, we will use fabric which allows running commands on remote hosts from python.

On your development machine run:

pipenv install --dev fabric3

(and NOT fabric which is not compatible with python 3).

Defining and running tasks with fabric

Fabric uses a fabfile to store reusable tasks.

Create a new MyProject/fabfile.py with:

from fabric.api import *

@task
def foo():
    print("FOO!!!!")


@task
def bar():
    print("BAR!!")

Now try running the tasks with:

fab foo
fab bar
fab foo bar bar foo

Executing Commands On Remote Hosts

Use run() to execute commands on a remote host:

Change your fabfile.py to include:

from fabric.api import *

env.user = "sysop"
env.hosts = ["myproject.mydomain.com"]


@task
def host_type():
    run("uname -a")


@task
def uptime():
    run("uptime")

and run::

fab host_type uptime

Tips

To execute a command as root from a fabfile with sudo use one of:

sudo("cmd")
run("sudo cmd")
run("cmd", use_sudo=True)

Refer to fabric's docs for more info.