derper

#!/usr/bin/env python

import subprocess
import sys
import os
import json
import os.path 

config = None
RC_FILE = os.path.expanduser('~/.derperrc')
GIT_ORIGIN = "git@github.com:"


def exit_gracefully(exit_code=0):
    with open(RC_FILE, 'w') as fp:
        json.dump(config, fp)
    exit(exit_code)


def print_help(chapter=None):
    chapters = {
        'config':
"""
remote set      Set the remote to a GitHub repository.                
                `derper remote set FitMango/Derper`

remote remove   Remove the configured remote
                `derper remote remove`
"""
    }

    if chapter is None:
        print '\n'.join([v for _, v in chapters.iteritems()])
    else:
        print chapters[chapter]
    exit_gracefully()


def check_config_file():
    """
    Checks for the existence of a derperrc in the home dir.
    If it doesn't exist, creates one.
    
    Arguments:
        None

    Returns:
        True if it existed previously, False if it was created
    """
    if not os.path.isfile(RC_FILE):
        with open(RC_FILE,'w') as f: 
            return False
    return True


def load_config():
    if check_config_file():
        with open(RC_FILE, 'r+') as rc:    
            global config
            config = json.load(rc)
    else:
        config = {}


def arg_expand(cmd, prefix=None):
    """
    Returns an array consisting of that option, as well as that 
    option prefixed with --, plus its single-char representation.
    If prefix is specified, uses that instead of first character.

    Arguments:
        cmd (str): The command to prefix
        prefix (str): The single-character of that command

    Returns:
        str[] all options that could be used to 'mean' that cmd
    """

    if prefix is None:
        prefix = cmd[0]

    return [cmd, '--' + cmd, prefix, '-' + prefix]


def configure(args):
    if len(args) == 0:
        print_help('config')
    
    if args[0] == "remote":
        # We're modifying the remote. Let's edit the derperrc.
        if len(args) is 1:
            print config['remote']
            exit_gracefully()
        if args[1] == "add":
            if "remote" in config:
                print("Remote is already set to {}." +
                      "Remove before adding a new one.".format(config["remote"]))
                exit_gracefully(1)
            else:
                config['remote'] = args[2]
        elif args[1] == "remove":
            del config['remote']
    elif args[0] == "url":
        # We're modifying the url. Let's edit the derperrc.
        if len(args) is 1:
            print config['url']
            exit_gracefully()
        if args[1] == "add":
            if "url" in config:
                print("URL is already set to {}." +
                      "Remove before adding a new one.".format(config['url']))
                exit_gracefully(1)
            else:
                config['url'] = args[2]
        elif args[1] == "remove":
            del config['url']
    exit_gracefully()


def cleanup():
    # Kill all the temps.
    subprocess.call('killall mongod', shell=True)
    subprocess.call('killall node', shell=True)
    subprocess.call('rm -rf {}/*'.format(os.path.expanduser('~/.derper_files')), shell=True)
    subprocess.call('mkdir {}/logs'.format(os.path.expanduser('~/.derper_files')), shell=True)
    config['port'] = 3000
    exit_gracefully()


def broadcast(cmd):
    subprocess.call("for d in {}/de_*/ ; do (cd \"$d\" && {}); done".format(os.path.expanduser('~/.derper_files'), cmd), shell=True)


def add_to_nginx(branch, port):
    text = """
    server {
        listen   80;
        server_name %s;
       
        location / {
            auth_basic "Restricted";
            auth_basic_user_file /etc/nginx/.htpasswd;
            proxy_pass http://0.0.0.0:%s;
            proxy_set_header Host $host;
            proxy_set_header X-Real-IP $remote_addr;
            proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        }
    }
    """ % (branch + "." + config["url"], port)

    with open(os.path.expanduser('~/.derper_files/default'), 'a') as fh:
        fh.write(text + '\n')

def roll_nginx():
    subprocess.call(['sudo', 'mv', os.path.expanduser('~/.derper_files/default'), '/etc/nginx/sites-available/default'])
    subprocess.check_call('sudo service nginx reload', shell=True)
    subprocess.call(['sudo', 'cp', '/etc/nginx/sites-available/default', os.path.expanduser('~/.derper_files/default')])

def serve(args):
    if "next_port" not in config:
        config["next_port"] = 3000

    branch = args[0]

    subprocess.check_call("git clone {}{} {}/.derper_files/de_{}".format(GIT_ORIGIN, config['remote'], os.path.expanduser('~'), args[0]), shell=True)
    subprocess.check_call('cd {} && git checkout {} && meteor --settings settings.json --port {} > ../logs/{} &'.format(os.path.expanduser('~/.derper_files/de_' + branch), branch, config["next_port"], branch), shell=True)
    
    add_to_nginx(branch, config["next_port"])

    config["next_port"] += 2
    exit_gracefully()


def main(args):
    check_config_file()
    load_config()

    if len(args) < 1 or args[0] in arg_expand('help'):
        print_help()

    if args[0] in arg_expand('config'):
        configure(args[1:])

    if args[0] in arg_expand('serve'):
        serve(args[1:])

    if args[0] in arg_expand('broadcast'):
        broadcast(''.join(args[1:]))

    if args[0] == 'roll':
        roll_nginx()

    if args[0] in arg_expand('cleanup', 'r'):
        cleanup()

    return


if __name__ == "__main__":
    main(sys.argv[1:])