fabfile.py

#!/usr/bin/env python

# -- coding: utf-8 --

"""Deployment script.
This script is coded so it can make the deployments automagically in the
designed servers, it also works as a documentation of where are the programs
installed.
USE: fab <hosts>:<username> <action>
EX: fab staging:admin release
"""
import os
import datetime
from contextlib import contextmanager
from fabric.api import env, run, local, require, put, lcd, prefix

from fabric.contrib.files import exists


env.project_name = 'sma'

env.tar = '%s-%s.tar.gz' % (
    env.project_name,
    datetime.datetime.now().strftime('%Y%m%d%H%M%S'),
)
env.bundle = '%s-static.tar.gz' % (
    env.project_name,
)
env.use_ssh_config = True


@contextmanager
def virtualenv():
    with prefix('. %(venv_dir)s/bin/activate' % env):
        yield


def production(username, host):
    """Production environment."""
    env.hosts = host
    env.user = username
    base_dir = '/home/%s' % username
    name = env.project_name
    env.static_dir = os.path.join(base_dir, 'sites', '%s_web' % name)
    env.deploy_dir = os.path.join(base_dir, 'sites', '%s_service' % name)
    env.venv_dir = os.path.join(base_dir, 'venvs', name)
    env.server_command = os.path.join(env.deploy_dir, 'apache2/bin/restart')


def setup_env():
    """
    Creates required directories for deployment.
    It also attempts to install pip requirements on remote host.
    While not intended you might run it for local setup.
    """

    dirs = (env[x] for x in env if x.endswith('_dir'))

    for directory in dirs:
        if not exists(directory):
            run('mkdir -p %s' % directory)

    if not exists('%(venv_dir)s/bin/activate' % env):
        run('virtualenv -q -ppython3 %(venv_dir)s' % env)

    put('service/requirements.txt', 'requirements.txt')

    with virtualenv():
        run('pip -q install -U pip')
        run('pip -q install -Ur requirements.txt')


def upload_service(rev='HEAD'):
    """
    Create a tarball honoring git's ignored and non-tracked files,
    uploads it and decompresses it in the rigth path.
    """
    require('host', provided_by=[production])
    require('deploy_dir', provided_by=[production])
    require('venv_dir', provided_by=[production])

    tar = env.tar
    with lcd('service'):
        local('git archive %s -o %s' % (rev, tar))
        put(tar, tar)

        run('tar xfz %s -C %s' % (tar, env.deploy_dir))
        run('rm %s' % tar)
        local('rm %s' % tar)


def build_static_bundle():
    """
    Create a tarball of the static files
    to be uploaded later.
    It invokes django's collectstatic method and
    runs a regular grunt build.
    Requires your local development environment to be activated and the
    `manage` management command to be available.
    """

    require('project_name', provided_by=[production])
    require('static_dir')
    require('bundle')

    local('manage collectstatic --noinput')

    with lcd('web'):
        local('grunt build')
        local('tar cf %s -C ./build/ .' % env.bundle)
        local('mv %s ../' % env.bundle)


def upload_static(force=False):
    """
    Uploads `env.bundle` and decompresses it in the right path
    This will attempt to create and delete local gzips.
    Cleanup is not always what it should...
    """
    require('project_name', provided_by=[production])
    require('static_dir', provided_by=[production])

    bundle_path = os.path.join(os.path.dirname(__file__), env.bundle)

    if force or not os.path.exists(bundle_path):
        build_static_bundle()

    put(bundle_path, env.bundle)

    run('tar xf %s -C %s' % (env.bundle, env.static_dir))
    run('rm %s' % env.bundle)
    local('rm %s' % bundle_path)


def release(rev='HEAD', force=False):
    """
    End-to-end release.
    It's a wrapper for the other functions.
    """
    require('host', provided_by=[production])
    setup_env()
    upload_service(rev=rev)
    upload_static(force=force)


def apache_restart():
    """Restart the program in the servers."""
    require('server_command', provided_by=[production])
    run(env.server_command)