Module: RubyAemAws::HealthyCountVerifier

Defined in:
lib/ruby_aem_aws/mixins/healthy_count_verifier.rb

Overview

Mixin for checking health of a component via ELB ‘healthy’ count vs ASG desired_capacity. Add this to a component to make it capable of determining its own health.

Instance Method Summary collapse

Instance Method Details

#health_state ⇒ Object

Provides detail of the state of the instances comprising the component.

  • no_asg: AutoScalingGroup could not be located (by StackPrefix and Component tags).

  • no_elb: ElasticLoadBalancer could not be located (by StackPrefix and aws:cloudformation:logical-id tags).

  • misconfigured: AutoScalingGroup.desired_capacity is less than 1.

  • recovering: ELB running instance count is less than AutoScalingGroup.desired_capacity.

  • scaling: ELB running instance count is more than AutoScalingGroup.desired_capacity.

  • ready: ELB running instance count is equal to AutoScalingGroup.desired_capacity.

Returns:

  • one of:



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# File 'lib/ruby_aem_aws/mixins/healthy_count_verifier.rb', line 35

def health_state
  asg = find_auto_scaling_group(asg_client)
  return :no_asg if asg.nil?

  # Debug:
  # unless asg.nil?
  #   puts("ASG: #{asg} #{asg.auto_scaling_group_name} (#{asg.desired_capacity})")
  #   asg.instances.each do |i|
  #     puts("  Instance #{i.instance_id}: #{i.health_status}")
  #   end
  # end

  elb = find_elb(elb_client)
  return :no_elb if elb.nil?

  elb_running_instances = 0
  elb_instances = get_instances_state(elb_client, elb)
  return :no_elb_targets if elb_instances.nil?

  elb_instances.each do |i|
    elb_running_instances += 1 if i[:state] == RubyAemAws::Constants::INSTANCE_STATE_HEALTHY
  end

  desired_capacity = asg.desired_capacity

  return :misconfigured if desired_capacity < 1
  return :recovering if elb_running_instances < desired_capacity
  return :scaling if elb_running_instances > desired_capacity

  :ready
end

#healthy? ⇒ Boolean

Aggregate health_states considered healthy.

Returns:

  • (Boolean) —

    health_state is ready or scaling.



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# File 'lib/ruby_aem_aws/mixins/healthy_count_verifier.rb', line 23

def healthy?
  %i[ready scaling].include? health_state
end

#wait_until_healthy ⇒ Object

Returns true, if all EC2 instances within the ELB are running.

Returns:

  • true, if all EC2 instances within the ELB are running

Raises:



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# File 'lib/ruby_aem_aws/mixins/healthy_count_verifier.rb', line 68

def wait_until_healthy
  raise ELBMisconfiguration if health_state.eql?(:misconfigured)

  sleep 60 while health_state.eql?(:recovering) || health_state.eql?(:scaling)
  return true if health_state.eql?(:ready)
end