orchestrate.py

#! /usr/bin/python3

import argparse
import importlib
import json
import os
import subprocess
import sys

DEFAULT_ACTIONS = ['files', 'init', 'check']

parser = argparse.ArgumentParser(description='terraform cluster orchestrator')
parser.add_argument('-c', '--config',
                    help='Terraform output for using by orchestrator (default: -)', default='-')
parser.add_argument('actions', metavar='ACTIONS', nargs='*',
                    help='actions (default: %s)' % ' '.join(DEFAULT_ACTIONS),
                    default=DEFAULT_ACTIONS)
parser.add_argument('-n', '--dry-run', action='store_true',
                    help='simulated run')
parser.add_argument('-p', '--parameters',
                    help='orchestration parameters')
args = parser.parse_args()

j = None
if args.config == '-':
    j = json.load(sys.stdin)
else:
    with open(args.config) as f:
        j = json.load(f)

config = j['config']['value']
n = config['n']
d = config['domain']
hosts = j['hosts']['value']
public_hosts = j['public_hosts']['value']
master_hostname = config['master_hostname']
master_ip = public_hosts[master_hostname]
user = config['image_user']
t = config.get('type', None)

print('== plugin ==')
if t and os.path.exists('%s/plugin.py' % t):
    print('-> %s/plugin.py' % t)
    plugin = importlib.import_module(f'%s.plugin' % t)
    Component = getattr(plugin, 'Component')
    component = Component(args, config, hosts)
else:
    component = None

if 'files' in args.actions:
    print('== files ==')
    print('-> hosts')
    if not args.dry_run:
        with open('hosts', 'w') as f:
            f.write('''\
127.0.0.1	localhost

# The following lines are desirable for IPv6 capable hosts
::1     localhost ip6-localhost ip6-loopback
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

''')
            for h, ip in hosts.items():
                f.write('%s	%s.%s	%s.%s.	%s\n' % (ip, h, d, h, d, h))

    print('-> public_hosts')
    if not args.dry_run:
        with open('public_hosts', 'w') as f:
            for h, ip in public_hosts.items():
                f.write('%s	%s.%s	%s.%s.	%s\n' % (ip, h, d, h, d, h))

    print('-> inventory')
    if not args.dry_run:
        with open('inventory', 'w') as f:
            f.write('''\
[masters]
%s ansible_user=%s ansible_become=true ansible_host=%s

[nodes]
''' % (master_hostname, user, master_ip))
            for h, ip in hosts.items():
                if h == master_hostname:
                    continue
                f.write('\
%s ansible_user=%s ansible_become=true ansible_host=%s ansible_ssh_common_args=\'\
-o ForwardAgent=yes -o ProxyCommand="ssh -W %s:22 -q %s@%s"\'\n' % (h, user, ip, ip, user,
                                                                    master_ip))
    if component:
        component.action('files')

if 'init' in args.actions:
    print('== init ==')

    h = list(hosts.keys()) + ['%s.%s.' % (host, d) for host in hosts.keys()] + \
        ['%s.%s' % (host, d) for host in hosts.keys()] + list(hosts.values()) + [master_ip]

    commands = [
        ['ssh-keygen', '-R', master_ip],
        ['ssh', '-o', 'StrictHostKeyChecking=no', '%s@%s' % (user, master_ip), ':'],
        ['scp', '-p', 'hosts', '%s@%s:/tmp/' % (user, master_ip)],
        ['ssh', '%s@%s' % (user, master_ip), 'sudo mv -v /tmp/hosts /etc/hosts'],
        ['ssh', '-o', 'ForwardAgent=yes', '%s@%s' % (user, master_ip),
         'for h in %s; do ssh -o StrictHostKeyChecking=no %s@$h :; done' % (' '.join(h), user)],
    ]
    for ip in hosts.values():
        commands += [
            ['ssh-keygen', '-R', ip],
            ['ssh', '-o', 'ForwardAgent=yes', '-o', 'ProxyCommand=ssh -W %s:22 -q %s@%s' %
             (ip, user, master_ip), '-o', 'StrictHostKeyChecking=no', '%s@%s' % (user, ip), ':']
        ]
    commands += [
        ['ansible', '-i', './inventory', '-m', 'copy', '-a', 'src=hosts dest=/etc/hosts', 'nodes'],
    ]
    if component:
        commands += component.init_commands()

    for cmd in commands:
        print('-> %s' % ' '.join(cmd))
        if not args.dry_run:
            subprocess.run(cmd)
    if component:
        component.action('init')

if 'check' in args.actions:
    print('== check ==')

    commands = [
        ['ansible', '-i', './inventory', '-m', 'command', '-a', 'uname -a', 'all']
    ]

    for cmd in commands:
        print('-> %s' % ' '.join(cmd))
        if not args.dry_run:
            subprocess.run(cmd)
    if component:
        component.action('check')