manage.py

import os, sys, argparse, subprocess, signal

# Tip from:
# https://github.com/dpgaspar/Flask-AppBuilder/issues/733#issuecomment-379009480
PORT = int(os.environ.get("PORT", 3000))

# Project defaults
FLASK_APP = 'server/__init__.py'
DEFAULT_IP = '0.0.0.0:' + str(PORT)

class Command:
    def __init__(self, name, descr, runcmd, env={}):
        self.name = name
        self.descr = descr
        self.runcmd = runcmd
        self.env = env

    def run(self, conf):
        cmd = self.runcmd(conf)
        env = os.environ
        env.update(conf)
        env.update(self.env)
        subprocess.call(cmd, env=env)


class CommandManager:
    def __init__(self):
        self.commands = {}

    def add(self, command):
        self.commands[command.name] = command

    def configure(self, conf):
        self.conf = conf

    def run(self, command):
        if command in self.commands:
            self.commands[command].run(self.conf)
        else:
            print("invalid command specified\n")
            print(self.availableCommands())

    def availableCommands(self):
        commands = sorted(self.commands.values(), key=lambda c: c.name)
        space = max([len(c.name) for c in commands]) + 2
        description = 'available subcommands:\n'
        for c in commands:
            description += '  ' + c.name + ' ' * (space - len(c.name)) + c.descr + '\n'
        return description


cm = CommandManager()

cm.add(Command(
    "build",
    "compiles python files in project into .pyc binaries",
    lambda c: ['python', '-m', 'compileall', '.']))

cm.add(Command(
    "start",
    "runs server with gunicorn in a production setting",
    lambda c: ['gunicorn', '-b', c['host'] + ':' + c['port'], 'server:app'],
    {
        'FLASK_APP': FLASK_APP,
        'FLASK_DEBUG': 'false'
    }))

cm.add(Command(
    "run",
    "runs dev server using Flask's native debugger & backend reloader",
    lambda c: ['python', '-m', 'flask', 'run', '--host=' + c['host'], '--port=' + c['port'], '--debugger', '--reload'],
    {
        'FLASK_APP': FLASK_APP,
        'FLASK_DEBUG': 'true'
    }))

cm.add(Command(
    "livereload",
    "runs dev server using livereload for dynamic webpage reloading",
    lambda c: ['python', '-m', 'flask', 'run'],
    {
        'FLASK_APP': FLASK_APP,
        'FLASK_LIVE_RELOAD': 'true',
    }))

cm.add(Command(
    "debug",
    "runs dev server in debug mode; use with an IDE's remote debugger",
    lambda c: ['python', '-m', 'flask', 'run', '--host=' + c['host'], '--port=' + c['port'], '--no-debugger', '--no-reload'],
    {
        'FLASK_APP': FLASK_APP,
        'FLASK_DEBUG': 'true'
    }))

cm.add(Command(
    "test",
    "runs all tests inside of `tests` directory",
    lambda c: ['python', '-m', 'unittest', 'discover', '-s', 'tests', '-p', '"*.py"']))

# Create and format argument parser for CLI
parser = argparse.ArgumentParser(description=cm.availableCommands(),
                                 formatter_class=argparse.RawDescriptionHelpFormatter)
parser.add_argument("subcommand", help="subcommand to run (see list above)")
parser.add_argument("ipaddress", nargs='?', default=DEFAULT_IP,
                    help="address and port to run on (i.e. 0.0.0.0:3000)")


def livereload_check():
    check = subprocess.call("lsof -n -i4TCP:3000", shell=True)
    if (check == 0):
        output = subprocess.check_output("pgrep Python", shell=True)
        pypid = int(output)
        os.kill(pypid, signal.SIGKILL)
        print("Discovered rogue Python process: {0}".format(pypid))
        print("Killing PID {0}...".format(pypid))
    else:
        print(" No rogue Python process running")


# Take in command line input for configuration
try:
    args = parser.parse_args()
    cmd = args.subcommand
    addr = args.ipaddress.split(':')
    cm.configure({
        'host': addr[0],
        'port': addr[1],
    })
    cm.run(cmd)
except KeyboardInterrupt:
    if 'FLASK_LIVE_RELOAD' in os.environ and os.environ['FLASK_LIVE_RELOAD'] == 'true':
        livereload_check()
except:
    if len(sys.argv) == 1:
        print(cm.availableCommands())
    sys.exit(0)