{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE TupleSections #-}

-- | To specify how AWS CloudFormation handles rolling updates for an Auto
-- Scaling group, use the AutoScalingRollingUpdatePolicy policy.

module Stratosphere.ResourceAttributes.AutoScalingRollingUpdatePolicy where

import Stratosphere.ResourceImports


-- | Full data type definition for AutoScalingRollingUpdatePolicy. See
-- 'autoScalingRollingUpdatePolicy' for a more convenient constructor.
data AutoScalingRollingUpdatePolicy =
  AutoScalingRollingUpdatePolicy
  { _autoScalingRollingUpdatePolicyMaxBatchSize :: Maybe (Val Integer)
  , _autoScalingRollingUpdatePolicyMinInstancesInService :: Maybe (Val Integer)
  , _autoScalingRollingUpdatePolicyMinSuccessfulInstancesPercent :: Maybe (Val Integer)
  , _autoScalingRollingUpdatePolicyPauseTime :: Maybe (Val Text)
  , _autoScalingRollingUpdatePolicySuspendProcesses :: Maybe (ValList Text)
  , _autoScalingRollingUpdatePolicyWaitOnResourceSignals :: Maybe (Val Bool)
  } deriving (Show, Eq)

instance ToJSON AutoScalingRollingUpdatePolicy where
  toJSON AutoScalingRollingUpdatePolicy{..} =
    object $
    catMaybes
    [ fmap (("MaxBatchSize",) . toJSON . fmap Integer') _autoScalingRollingUpdatePolicyMaxBatchSize
    , fmap (("MinInstancesInService",) . toJSON . fmap Integer') _autoScalingRollingUpdatePolicyMinInstancesInService
    , fmap (("MinSuccessfulInstancesPercent",) . toJSON . fmap Integer') _autoScalingRollingUpdatePolicyMinSuccessfulInstancesPercent
    , fmap (("PauseTime",) . toJSON) _autoScalingRollingUpdatePolicyPauseTime
    , fmap (("SuspendProcesses",) . toJSON) _autoScalingRollingUpdatePolicySuspendProcesses
    , fmap (("WaitOnResourceSignals",) . toJSON . fmap Bool') _autoScalingRollingUpdatePolicyWaitOnResourceSignals
    ]

-- | Constructor for 'AutoScalingRollingUpdatePolicy' containing required fields as
-- arguments.
autoScalingRollingUpdatePolicy
  :: AutoScalingRollingUpdatePolicy
autoScalingRollingUpdatePolicy  =
  AutoScalingRollingUpdatePolicy
  { _autoScalingRollingUpdatePolicyMaxBatchSize = Nothing
  , _autoScalingRollingUpdatePolicyMinInstancesInService = Nothing
  , _autoScalingRollingUpdatePolicyMinSuccessfulInstancesPercent = Nothing
  , _autoScalingRollingUpdatePolicyPauseTime = Nothing
  , _autoScalingRollingUpdatePolicySuspendProcesses = Nothing
  , _autoScalingRollingUpdatePolicyWaitOnResourceSignals = Nothing
  }

-- | Specifies the maximum number of instances that AWS CloudFormation
-- terminates.
asrupMaxBatchSize :: Lens' AutoScalingRollingUpdatePolicy (Maybe (Val Integer))
asrupMaxBatchSize = lens _autoScalingRollingUpdatePolicyMaxBatchSize (\s a -> s { _autoScalingRollingUpdatePolicyMaxBatchSize = a })

-- | Specifies the minimum number of instances that must be in service within
-- the Auto Scaling group while AWS CloudFormation terminates obsolete
-- instances.
asrupMinInstancesInService :: Lens' AutoScalingRollingUpdatePolicy (Maybe (Val Integer))
asrupMinInstancesInService = lens _autoScalingRollingUpdatePolicyMinInstancesInService (\s a -> s { _autoScalingRollingUpdatePolicyMinInstancesInService = a })

-- | Specifies the percentage of instances in an Auto Scaling rolling update
-- that must signal success for an update to succeed. You can specify a value
-- from 0 to 100. AWS CloudFormation rounds to the nearest tenth of a percent.
-- For example, if you update five instances with a minimum successful
-- percentage of 50, three instances must signal success. If an instance
-- doesn't send a signal within the time specified using the PauseTime
-- property, AWS CloudFormation assumes that the instance wasn't successfully
-- updated. If you specify this property, you must also enable the
-- WaitOnResourceSignals and PauseTime properties.
asrupMinSuccessfulInstancesPercent :: Lens' AutoScalingRollingUpdatePolicy (Maybe (Val Integer))
asrupMinSuccessfulInstancesPercent = lens _autoScalingRollingUpdatePolicyMinSuccessfulInstancesPercent (\s a -> s { _autoScalingRollingUpdatePolicyMinSuccessfulInstancesPercent = a })

-- | Specifies the amount of time that AWS CloudFormation should pause after
-- making a change to a batch of instances to give these instances time to
-- start software applications. For example, you might need PauseTime when
-- scaling up the number of instances in an Auto Scaling group. If you enable
-- the WaitOnResourceSignals property, PauseTime is the amount of time AWS
-- CloudFormation should wait for the Auto Scaling group to receive the
-- required number of valid signals from added or replaced instances. If the
-- PauseTime is exceeded before the Auto Scaling group receives the required
-- number of signals, the update fails. For best results, specify a time
-- period that gives your instances sufficient time to get started. If the
-- update needs to be rolled back, a short PauseTime can cause the rollback to
-- fail. Specify PauseTime in the ISO8601 duration format (in the format
-- PT#H#M#S, where each # is the number of hours, minutes, and seconds,
-- respectively). The maximum PauseTime is one hour (PT1H).
asrupPauseTime :: Lens' AutoScalingRollingUpdatePolicy (Maybe (Val Text))
asrupPauseTime = lens _autoScalingRollingUpdatePolicyPauseTime (\s a -> s { _autoScalingRollingUpdatePolicyPauseTime = a })

-- | Specifies the Auto Scaling processes to suspend during a stack update.
-- Suspending processes prevents Auto Scaling from interfering with a stack
-- update. For example, you can suspend alarming so that Auto Scaling doesn't
-- execute scaling policies associated with an alarm. For valid values, see
-- the ScalingProcesses.member.N parameter for the SuspendProcesses action in
-- the Auto Scaling API Reference.
asrupSuspendProcesses :: Lens' AutoScalingRollingUpdatePolicy (Maybe (ValList Text))
asrupSuspendProcesses = lens _autoScalingRollingUpdatePolicySuspendProcesses (\s a -> s { _autoScalingRollingUpdatePolicySuspendProcesses = a })

-- | Specifies whether the Auto Scaling group waits on signals from new
-- instances during an update. AWS CloudFormation suspends the update of an
-- Auto Scaling group after new Amazon EC2 instances are launched into the
-- group. AWS CloudFormation must receive a signal from each new instance
-- within the specified PauseTime before continuing the update. To signal the
-- Auto Scaling group, use the cfn-signal helper script or SignalResource API.
-- Use this property to ensure that instances have completed installing and
-- configuring applications before the Auto Scaling group update proceeds.
asrupWaitOnResourceSignals :: Lens' AutoScalingRollingUpdatePolicy (Maybe (Val Bool))
asrupWaitOnResourceSignals = lens _autoScalingRollingUpdatePolicyWaitOnResourceSignals (\s a -> s { _autoScalingRollingUpdatePolicyWaitOnResourceSignals = a })