#!/usr/bin/python
import argparse
import errno
import json
import logging
import os
import subprocess
import sys
import time


log = logging.getLogger(os.path.basename(sys.argv[0]))

QUORUM_STATES = ['leader', 'peon']

def wait_for_quorum(cluster, mon_id):
    while True:
        p = subprocess.Popen(
            args=[
                'ceph',
                '--cluster={cluster}'.format(cluster=cluster),
                '--admin-daemon=/var/run/ceph/{cluster}-mon.{mon_id}.asok'.format(
                    cluster=cluster,
                    mon_id=mon_id,
                    ),
                'mon_status',
                ],
            stdout=subprocess.PIPE,
            )
        out = p.stdout.read()
        returncode = p.wait()
        if returncode != 0:
            log.info('ceph-mon admin socket not ready yet.')
            time.sleep(1)
            continue

        data = json.loads(out)
        state = data['state']
        if state not in QUORUM_STATES:
            log.info('ceph-mon is not in quorum: %r', state)
            time.sleep(1)
            continue

        break


def get_key(cluster, mon_id):
    path = '/etc/ceph/{cluster}.client.admin.keyring'.format(
        cluster=cluster,
        )
    if os.path.exists(path):
        log.info('Key exists already: %s', path)
        return
    tmp = '{path}.{pid}.tmp'.format(
        path=path,
        pid=os.getpid(),
        )
    while True:
        try:
            with file(tmp, 'w') as f:
                os.fchmod(f.fileno(), 0600)
                log.info('Talking to monitor...')
                returncode = subprocess.call(
                    args=[
                        'ceph',
                        '--cluster={cluster}'.format(cluster=cluster),
                        '--name=mon.',
                        '--keyring=/var/lib/ceph/mon/{cluster}-{mon_id}/keyring'.format(
                            cluster=cluster,
                            mon_id=mon_id,
                            ),
                        'auth',
                        'get-or-create',
                        'client.admin',
                        'mon', 'allow *',
                        'osd', 'allow *',
                        'mds', 'allow',
                        ],
                    stdout=f,
                    )
            if returncode != 0:
                log.info('Cannot get or create admin key')
                time.sleep(1)
                continue

            os.rename(tmp, path)
            break
        finally:
            try:
                os.unlink(tmp)
            except OSError as e:
                if e.errno == errno.ENOENT:
                    pass
                else:
                    raise

def bootstrap_key(cluster, type_, caps):
    path = '/var/lib/ceph/bootstrap-{type}/{cluster}.keyring'.format(
        type=type_,
        cluster=cluster,
        )
    if os.path.exists(path):
        log.info('Key exists already: %s', path)
        return
    tmp = '{path}.{pid}.tmp'.format(
        path=path,
        pid=os.getpid(),
        )

    args = [
        'ceph',
        '--cluster={cluster}'.format(cluster=cluster),
        'auth',
        'get-or-create',
        'client.bootstrap-{type}'.format(type=type_),
        ]
    for subsystem, subcaps in caps.iteritems():
        args.extend([
            subsystem,
            '; '.join(subcaps),
            ])

    while True:
        try:
            with file(tmp, 'w') as f:
                os.fchmod(f.fileno(), 0600)
                log.info('Talking to monitor...')
                returncode = subprocess.call(
                    args=args,
                    stdout=f,
                    )
            if returncode != 0:
                log.info('Cannot get or create bootstrap key for %s', type_)
                time.sleep(1)
                continue

            os.rename(tmp, path)
            break
        finally:
            try:
                os.unlink(tmp)
            except OSError as e:
                if e.errno == errno.ENOENT:
                    pass
                else:
                    raise


def parse_args():
    parser = argparse.ArgumentParser(
        description='Create Ceph client.admin key when ceph-mon is ready',
        )
    parser.add_argument(
        '-v', '--verbose',
        action='store_true', default=None,
        help='be more verbose',
        )
    parser.add_argument(
        '--cluster',
        metavar='NAME',
        help='name of the cluster',
        )
    parser.add_argument(
        '--id', '-i',
        metavar='ID',
        help='id of a ceph-mon that is coming up',
        required=True,
        )
    parser.set_defaults(
        cluster='ceph',
        )
    parser.set_defaults(
        # we want to hold on to this, for later
        prog=parser.prog,
        )
    args = parser.parse_args()
    return args


def main():
    args = parse_args()

    loglevel = logging.INFO
    if args.verbose:
        loglevel = logging.DEBUG

    logging.basicConfig(
        level=loglevel,
        )

    wait_for_quorum(cluster=args.cluster, mon_id=args.id)
    get_key(cluster=args.cluster, mon_id=args.id)
    bootstrap_key(
        cluster=args.cluster,
        type_='osd',
        caps=dict(
            mon=[
                'allow command osd create ...',
                'allow command osd crush set ...',
                r'allow command auth add * osd allow\ * mon allow\ rwx',
                'allow command mon getmap',
                ],
            ),
        )


if __name__ == '__main__':
    main()