etcd.py 文件源码

def register_node_with_leader(cluster):
    '''
    Control flow mechanism to perform self registration with the leader.

    Before executing self registration, we must adhere to the nature of offline
    static turnup rules. If we find a GUID in the member list without peering
    information the unit will enter a race condition and must wait for a clean
    status output before we can progress to self registration.
    '''
    # We're going to communicate with the leader, and we need our bootstrap
    # startup string once.. TBD after that.
    etcdctl = EtcdCtl()
    bag = EtcdDatabag()
    # Assume a hiccup during registration and attempt a retry
    if bag.cluster_unit_id:
        bag.cluster = bag.registration_peer_string
        # conf_path = '{}/etcd.conf'.format(bag.etcd_conf_dir)
        render_config(bag)
        time.sleep(2)

    try:
        peers = etcdctl.member_list(leader_get('leader_address'))
    except CalledProcessError:
        log("Etcd attempted to invoke registration before service ready")
        # This error state is transient, and does not imply the unit is broken.
        # Erroring at this stage can be resolved, and should not effect the
        # overall condition of unit turn-up. Return from the method and let the
        # charm re-invoke on next run
        return

    for unit in peers:
        if 'client_urls' not in peers[unit].keys():
            # we cannot register. State not attainable.
            msg = 'Waiting for unit to complete registration.'
            status_set('waiting', msg)
            return

    if not bag.cluster_unit_id:
        bag.leader_address = leader_get('leader_address')
        resp = etcdctl.register(bag.__dict__)
        if resp and 'cluster_unit_id' in resp.keys() and 'cluster' in resp.keys():  # noqa
            bag.cache_registration_detail('cluster_unit_id',
                                          resp['cluster_unit_id'])
            bag.cache_registration_detail('registration_peer_string',
                                          resp['cluster'])

            bag.cluster_unit_id = resp['cluster_unit_id']
            bag.cluster = resp['cluster']

    render_config(bag)
    host.service_restart(bag.etcd_daemon)
    time.sleep(2)

    # Check health status before we say we are good
    etcdctl = EtcdCtl()
    status = etcdctl.cluster_health()
    if 'unhealthy' in status:
        status_set('blocked', 'Cluster not healthy.')
        return
    open_port(bag.port)
    set_state('etcd.registered')