def wait_for_healthok(instance):
logger.info("Waiting for instance to be Online %s", instance)
sys.stdout.write('Waiting')
while not is_everything_awesome(instance):
sys.stdout.write('.')
# Flush stdout so tmux updates
sys.stdout.flush()
time.sleep(10)
print("Ok, Everything is awesome!")
def wait_for_elb_state(instance, state):
logger.info("Waiting for %s to reach ELB state '%s'...", instance, state)
while True:
instance.update()
instance_state = instance.instance.state['Name']
if instance_state != 'running':
raise RuntimeError(
'Instance no longer running (state {})'.format(instance_state))
logger.debug("State is %s", instance.elb_health)
if instance.elb_health == state:
logger.info("...done")
return
time.sleep(5)
def instances_restart(cfg: Config, motd: str):
"""Restart the instances, picking up new code."""
if not are_you_sure(
'restart all instances with version {}'.format(
describe_current_release(cfg)), cfg):
return
begin_time = datetime.datetime.now()
# Store old motd
old_motd = update_motd(cfg, motd)
modified_groups: Dict[str, int] = {}
failed = False
to_restart = pick_instances(cfg)
for index, instance in enumerate(to_restart):
logger.info("Restarting %s (%d of %d)...", instance, index + 1,
len(to_restart))
as_instance_status = instance.describe_autoscale()
if not as_instance_status:
logger.warning("Skipping %s as it is no longer in the ASG",
instance)
continue
as_group_name = as_instance_status['AutoScalingGroupName']
if as_instance_status['LifecycleState'] != 'InService':
logger.warning("Skipping %s as it is not InService (%s)", instance,
as_instance_status)
continue
try:
restart_one_instance(as_group_name, instance, modified_groups)
except RuntimeError as e:
logger.error("Failed restarting %s - skipping: %s", instance, e)
failed = True
# TODO, what here?
for group, desired in iter(modified_groups.items()):
logger.info("Putting desired instances for %s back to %d", group,
desired)
as_client.update_auto_scaling_group(AutoScalingGroupName=group,
DesiredCapacity=desired)
update_motd(cfg, old_motd)
end_time = datetime.datetime.now()
delta_time = end_time - begin_time
print(f'Instances restarted in {delta_time.total_seconds()} seconds')
sys.exit(1 if failed else 0)
def restart_one_instance(as_group_name: str, instance: Instance,
modified_groups: Dict[str, int]):
instance_id = instance.instance.instance_id
logger.info("Enabling instance protection for %s", instance)
as_client.set_instance_protection(AutoScalingGroupName=as_group_name,
InstanceIds=[instance_id],
ProtectedFromScaleIn=True)
as_group = get_autoscaling_group(as_group_name)
adjustment_required = as_group['DesiredCapacity'] == as_group['MinSize']
if adjustment_required:
logger.info("Group '%s' needs to be adjusted to keep enough nodes",
as_group_name)
modified_groups[
as_group['AutoScalingGroupName']] = as_group['DesiredCapacity']
logger.info("Putting %s into standby", instance)
as_client.enter_standby(
InstanceIds=[instance_id],
AutoScalingGroupName=as_group_name,
ShouldDecrementDesiredCapacity=not adjustment_required)
wait_for_autoscale_state(instance, 'Standby')
logger.info("Restarting service on %s", instance)
restart_response = exec_remote(
instance, ['sudo', 'systemctl', 'restart', 'compiler-explorer'])
if restart_response:
logger.warning("Restart gave some output: %s", restart_response)
wait_for_healthok(instance)
logger.info("Moving %s out of standby", instance)
as_client.exit_standby(InstanceIds=[instance_id],
AutoScalingGroupName=as_group_name)
wait_for_autoscale_state(instance, 'InService')
wait_for_elb_state(instance, 'healthy')
logger.info("Disabling instance protection for %s", instance)
as_client.set_instance_protection(AutoScalingGroupName=as_group_name,
InstanceIds=[instance_id],
ProtectedFromScaleIn=False)
logger.info("Instance restarted ok")
