fabfile.py

from awsfabrictasks.ec2.api import *
from fabric.api import *
from functools import wraps

import boto.ec2.elb
import boto.ec2.connection
import boto.ec2.instance
import time


def aws_hosts(load_balancers):
    instances = []
    elb_conn = boto.ec2.elb.connect_to_region('us-west-2', profile_name="ourrevcms")
    for elb in elb_conn.get_all_load_balancers(load_balancer_names=load_balancers):
        instances.extend(elb.instances)

    if not instances:
      raise ValueError('No instances found! I\'m getting out of here.')

    ec2_conn = boto.ec2.connect_to_region('us-west-2', profile_name="ourrevcms")
    reservations = ec2_conn.get_all_instances([i.id for i in instances])

    ec2_hosts = {}
    for reservation in reservations:
        for i in reservation.instances:
            ec2_hosts[i.public_dns_name] = i.id

    return ec2_hosts


def elb_operation(operation, instance_id, loadBalancerNames):
    elb_conn =  boto.ec2.elb.connect_to_region('us-west-2', profile_name="ourrevcms")
    for lb in elb_conn.get_all_load_balancers(load_balancer_names=loadBalancerNames):
        getattr(lb, operation)(instance_id)


def remove_from_elbs():
    print "Removing %s from the load balancer..." % env.aws_hosts[env.host]
    elb_operation('deregister_instances', env.aws_hosts[env.host], env.load_balancer_name)
    time.sleep(5)    # allow connections to fully drain


def add_to_elbs():
    print "Adding %s back to the load balancer..." % env.aws_hosts[env.host]
    elb_operation('register_instances', env.aws_hosts[env.host], env.load_balancer_name)
    time.sleep(15)   # generous to prevent cascading effect of removing machines from ELB


def elb_managed(func):
    @wraps(func)
    def decorated(*args, **kwargs):

        if env.load_balancer_name:
            remove_from_elbs()

        func(*args, **kwargs)

        if env.load_balancer_name:
            add_to_elbs()

    return decorated


def production():
    env.load_balancer_name = ["ourrevcms"]
    env.aws_hosts = aws_hosts(env.load_balancer_name)
    env.hosts = env.aws_hosts.keys()
    env.forward_agent = True
    env.key_filename = '~/.ssh/hydra.pem'
    env.user = 'ubuntu'
    env.env_name = 'production'


# def staging():
#     env.load_balancer_name = None
#     env.hosts = ['ec2-35-162-6-125.us-west-2.compute.amazonaws.com']
#     env.forward_agent = True
#     env.key_filename = '~/.ssh/hydra.pem'
#     env.user = 'ubuntu'
#     env.env_name = 'staging'


@elb_managed
def deploy(pip_install=False, migrate=False, npm_install=False):

    with cd('/home/ubuntu/ourrevolution'):
        with prefix('source $(which virtualenvwrapper.sh)'):
            with prefix('workon ourrevolution'):

                run('supervisord -c supervisord.conf', warn_only=True)
                time.sleep(1)

                run('git checkout .')
                run('git pull origin master')

                if env.env_name == 'production':
                    run('supervisorctl stop gunicorn')


                if str(npm_install).lower() == 'true':
                    run('npm install')

                if str(pip_install).lower() == 'true':
                    run('pip install -r requirements.txt')

                if env.env_name == 'production':
                    run('./manage.py collectstatic --noinput')

                if str(migrate).lower() == 'true':
                    run('./manage.py migrate')


                if env.env_name != 'staging':
                    run('supervisorctl start gunicorn')


@elb_managed
def restart_gunicorn():

    with cd('ourrevolution'):
        with prefix('source $(which virtualenvwrapper.sh)'):
            with prefix('workon ourrevolution'):
                run('supervisorctl restart gunicorn')

@elb_managed
def config_set(**kwargs):
    if not kwargs:
        print "kwargs empty! Pass in a variable you want to set"
        print "e.g.: fab production config_set:DOUBLE_SECRET_PASSWORD=\"yolo\""
        exit(1)

    # this is going to get untenable... use with discretion!
    with cd('/home/ubuntu/.virtualenvs/ourrevolution/bin'):
        for key, value in kwargs.iteritems():
            run('echo "\nexport %s=%s" >> activate' % (key, value))

    with cd('/home/ubuntu/ourrevolution'):
        with prefix('source $(which virtualenvwrapper.sh)'):
            with prefix('workon ourrevolution'):
                # manually stop gunicorn

                run('supervisorctl stop gunicorn')

                # TODO: TECH-1402: need better graceful shutdown for celery tasks
                # Wait for celery tasks in progress to finish
                # time.sleep(600)

                kill_the_cat = run('cat supervisord.pid | xargs kill', warn_only=True)
                if kill_the_cat:
                    run('pkill supervisord', warn_only=True)
                time.sleep(2)
                run('supervisord -c /home/ubuntu/ourrevolution/supervisord.conf')
                time.sleep(2)
                run('supervisorctl reload -c /home/ubuntu/ourrevolution/supervisord.conf')

                run('supervisorctl start gunicorn')