gistfile1.py

$ cd /fabric/apib2b
$ fab -R prod deploy

================================================
/fabric/apib2b/fabfile.py

from worker import *

env.roledefs = {
    'int':  ['localhost', 'localhost', 'www3'],
    'prod': ['localhost', 'localhost', 'www2']
}

deployer = ApiB2b(env)

@task
def deploy():
    deployer.deploy_code()

============================================
/fabric/apib2b/worker.py

import sys

from fabric.api import *
from fabric.context_managers import settings


sys.path.insert(0, '/fabric/')
from Worker import Worker


class ApiB2b(Worker):
    def doDeployment(self):
        print "doing actual deployment!"
        self.stop_tomcat()
        self.updateGit()
        self.start_tomcat()

    def stop_tomcat(self):
        self.info("stopping tomcat")
        self.success("stopped tomcat")


    def start_tomcat(self):
        self.info("starting tomcat")
        self.success("started tomcat")

    def updateGit(self):
        code_dir = '/fabric/xx-xx.git'
        with settings(warn_only=True):
            if run("test -d %s" % code_dir).failed:
                self.info("directory does not exist! cloning new one .....")
                run("git clone git@xxx/xx-xx.git %s" % code_dir)
            else:
                with cd(code_dir):
                    run("git log")
                    
===================================

/fabric/Worker.py

from fabric.colors import red, green, yellow

class Worker(object):
    GIT_URL = "ssh://mygitserver/project"
    DEPLOYED = '/opt/project/deployed/{}'
    DEPLOYED_DIR = '/opt/project/deployed'

    def __init__(self, env):
        self.env = env

    def doDeployment(self):
        raise NotImplementedError

    def deploy_code(self):
        self.info("starting deployment")
        self.info("using hosts: %s" % self.env.hosts)
        self.doDeployment()
        current = self.DEPLOYED.format('current')
        # run('ln -s {} {}'.format(env.deploy, current))

    def info(self, msg):
        print(yellow("INFO: %s " % msg))

    def success(self, msg):
        print(green("SUCCESS: %s " % msg))

    def warn(self, msg):
        print(red("WARN: %s " % msg))