okd/bin/cluster

#!/usr/bin/env python
# vim: expandtab:tabstop=4:shiftwidth=4

import argparse
import ConfigParser
import sys
import os


class Cluster(object):
    """
    Control and Configuration Interface for OpenShift Clusters
    """
    def __init__(self):
        # setup ansible ssh environment
        if 'ANSIBLE_SSH_ARGS' not in os.environ:
            os.environ['ANSIBLE_SSH_ARGS'] = (
                '-o ForwardAgent=yes '
                '-o StrictHostKeyChecking=no '
                '-o UserKnownHostsFile=/dev/null '
                '-o ControlMaster=auto '
                '-o ControlPersist=600s '
            )

    def create(self, args):
        """
        Create an OpenShift cluster for given provider
        :param args: command line arguments provided by user
        :return: exit status from run command
        """
        env = {'cluster_id': args.cluster_id}
        playbook = "playbooks/{}/openshift-cluster/launch.yml".format(args.provider)
        inventory = self.setup_provider(args.provider)

        env['num_masters'] = args.masters
        env['num_nodes'] = args.nodes

        return self.action(args, inventory, env, playbook)

    def terminate(self, args):
        """
        Destroy OpenShift cluster
        :param args: command line arguments provided by user
        :return: exit status from run command
        """
        env = {'cluster_id': args.cluster_id}
        playbook = "playbooks/{}/openshift-cluster/terminate.yml".format(args.provider)
        inventory = self.setup_provider(args.provider)

        return self.action(args, inventory, env, playbook)

    def list(self, args):
        """
        List VMs in cluster
        :param args: command line arguments provided by user
        :return: exit status from run command
        """
        env = {'cluster_id': args.cluster_id}
        playbook = "playbooks/{}/openshift-cluster/list.yml".format(args.provider)
        inventory = self.setup_provider(args.provider)

        return self.action(args, inventory, env, playbook)

    def update(self, args):
        """
        Update to latest OpenShift across clustered VMs
        :param args: command line arguments provided by user
        :return: exit status from run command
        """
        env = {'cluster_id': args.cluster_id}
        playbook = "playbooks/{}/openshift-cluster/update.yml".format(args.provider)
        inventory = self.setup_provider(args.provider)

        return self.action(args, inventory, env, playbook)

    def setup_provider(self, provider):
        """
        Setup ansible playbook environment
        :param provider: command line arguments provided by user
        :return: path to inventory for given provider
        """
        config = ConfigParser.ConfigParser()
        if 'gce' == provider:
            config.readfp(open('inventory/gce/gce.ini'))

            for key in config.options('gce'):
                os.environ[key] = config.get('gce', key)

            inventory = '-i inventory/gce/gce.py'
        elif 'aws' == provider:
            config.readfp(open('inventory/aws/ec2.ini'))

            for key in config.options('ec2'):
                os.environ[key] = config.get('ec2', key)

            inventory = '-i inventory/aws/ec2.py'
        else:
            # this code should never be reached
            raise ValueError("invalid PROVIDER {}".format(provider))

        return inventory

    def action(self, args, inventory, env, playbook):
        """
        Build ansible-playbook command line and execute
        :param args: command line arguments provided by user
        :param inventory: derived provider library
        :param env: environment variables for kubernetes
        :param playbook: ansible playbook to execute
        :return: exit status from ansible-playbook command
        """

        verbose = ''
        if args.verbose > 0:
            verbose = '-{}'.format('v' * args.verbose)

        ansible_env = '-e \'{}\''.format(
            ' '.join(['%s=%s' % (key, value) for (key, value) in env.items()])
        )

        command = 'ansible-playbook {} {} {} {}'.format(
            verbose, inventory, ansible_env, playbook
        )

        if args.verbose > 1:
            command = 'time {}'.format(command)

        if args.verbose > 0:
            sys.stderr.write('RUN [{}]\n'.format(command))
            sys.stderr.flush()

        return os.system(command)


if __name__ == '__main__':
    """
    Implemented to support writing unit tests
    """

    cluster = Cluster()

    providers = ['gce', 'aws']
    parser = argparse.ArgumentParser(
        description='Python wrapper to ensure proper environment for OpenShift ansible playbooks',
    )
    parser.add_argument('-v', '--verbose', action='count', help='Multiple -v options increase the verbosity')
    parser.add_argument('--version', action='version', version='%(prog)s 0.2')

    meta_parser = argparse.ArgumentParser(add_help=False)
    meta_parser.add_argument('provider', choices=providers, help='provider')
    meta_parser.add_argument('cluster_id', help='prefix for cluster VM names')

    action_parser = parser.add_subparsers(dest='action', title='actions', description='Choose from valid actions')

    create_parser = action_parser.add_parser('create', help='Create a cluster', parents=[meta_parser])
    create_parser.add_argument('-m', '--masters', default=1, type=int, help='number of masters to create in cluster')
    create_parser.add_argument('-n', '--nodes', default=2, type=int, help='number of nodes to create in cluster')
    create_parser.set_defaults(func=cluster.create)

    terminate_parser = action_parser.add_parser('terminate', help='Destroy a cluster', parents=[meta_parser])
    terminate_parser.add_argument('-f', '--force', action='store_true', help='Destroy cluster without confirmation')
    terminate_parser.set_defaults(func=cluster.terminate)

    update_parser = action_parser.add_parser('update', help='Update OpenShift across cluster', parents=[meta_parser])
    update_parser.add_argument('-f', '--force', action='store_true', help='Update cluster without confirmation')
    update_parser.set_defaults(func=cluster.update)

    list_parser = action_parser.add_parser('list', help='List VMs in cluster', parents=[meta_parser])
    list_parser.set_defaults(func=cluster.list)

    args = parser.parse_args()

    if 'terminate' == args.action and not args.force:
        answer = raw_input("This will destroy the ENTIRE {} environment. Are you sure? [y/N] ".format(args.cluster_id))
        if answer not in ['y', 'Y']:
            sys.stderr.write('\nACTION [terminate] aborted by user!\n')
            exit(1)

    if 'update' == args.action and not args.force:
        answer = raw_input("This is destructive and could corrupt {} environment. Continue? [y/N] ".format(args.cluster_id))
        if answer not in ['y', 'Y']:
            sys.stderr.write('\nACTION [update] aborted by user!\n')
            exit(1)

    status = args.func(args)
    if status != 0:
        sys.stderr.write("ACTION [{}] failed with exit status {}\n".format(args.action, status))
    exit(status)