An example deployment using Fabric and Symlinks

fabfile-symlink.py

# -*- coding: utf-8 -*-
import os
import random
import requests
import json
import datetime

from fabric.api import *

"""
    Set up servers locations. This can be programatically generated too.
"""
env.roledefs = {
    'training': ['10.0.0.1'],
    'web': ['10.0.1.1', '10.0.1.2'],
}

"""
    Set up various environment variables for the application path, virtualenv,
    pip and requirements files for later use.
"""
RELEASE_TIMESTAMP = datetime.datetime.today().strftime('%Y%m%d%H%M%S')
env.directory = '/var/www/app'
env.repo_url = "GIT URL FOR REPO"
env.release_dir = '{}-{}'.format(env.directory, RELEASE_TIMESTAMP)

PRODUCTION = "production"
TRAINING = "training"

def git_clone():
    run("git clone {} .".format(env.repo_url))

@roles("web")
@parallel
def update_frontend():
    # Take ownership of project
    sudo('mkdir -p {}'.format(env.release_dir))

    with cd(env.release_dir):
        git_clone()
        run('npm set progress=false')
        run('npm install')

@roles("web")
@parallel
def build_frontend():
    with cd(env.release_dir):
        run('npm run build')

@roles("web")
@parallel
def restart_frontend():
    sudo('ln -sfn {} {}'.format(env.release_dir, env.directory))
    sudo("service nginx restart")


"""
    Here's the entry point for our fabfile. We can run this by typing `fab deploy` (for training)
    or `fab deploy:production` to deploy to production.
"""
def deploy(environment=TRAINING):
    execute('update_frontend')
    execute('build_frontend')
    execute('restart_frontend')