VPCZoneIdentifier is always an array - 1.0.0.pre

[gergnz]

There is a regression that I need to come up with a small example of in 1.0.0.pre.

In an autoscaling group VPCZoneIdentifier is an array, but I have template which builds this array. CFNDSL wants to make this an array regardless, which means I end up with an array of arrays which then CloudFormation doesn't like.

/cc @lwoggardner

[gergnz]

# frozen_string_literal: true

require 'cfndsl'

CloudFormation do
  params = {}
  external_parameters.each_pair do |key, val|
    key = key.to_sym
    params[key] = val
  end

  Parameter(:public) do
    Description 'Put the ECS Cluster in the Public space or App space'
    Type 'String'
    Default 'false'
  end

  Condition(
    :public, FnEquals(Ref(:public), 'true')
  )

  AutoScaling_AutoScalingGroup(:asg) do
    # rubocop:disable Metrics/LineLength
    VPCZoneIdentifier FnIf(:public, %w[a b c].map { |az| FnImportValue(FnJoin('-', [FnSelect('0', FnSplit('-', Ref('AWS::StackName'))), 'vpc', "publicsubnet#{az}"])) }, %w[a b c].map { |az| FnImportValue(FnJoin('-', [FnSelect('0', FnSplit('-', Ref('AWS::StackName'))), 'vpc', "appsubnet#{az}"])) })
    # rubocop:enable Metrics/LineLength
  end
end

command:

cfndsl x.rb -f yaml

0.17.4:

Resources:
  asg:
    Properties:
      VPCZoneIdentifier:
        Fn::If:
        - public
        - - Fn::ImportValue:

1.0.0.pre

Resources:
  asg:
    Type: AWS::AutoScaling::AutoScalingGroup
    Properties:
      VPCZoneIdentifier:
      - Fn::If:
        - public
        - - Fn::ImportValue:

note that 0.17.4 does not wrap VPCZoneIdentifier in an array, but 1.0.0.pre does.

[gergnz]

https://github.com/cfndsl/cfndsl/blob/1.0.0.pre/lib/cfndsl/jsonable.rb#L60

@@ -57,7 +57,7 @@ module CfnDsl

     # Equivalent to the Cloudformation template built in function Fn::If
     def FnIf(condition_name, true_value, false_value)
-      Fn.new('If', [condition_name, true_value, false_value])
+      Fn.new('If', [condition_name, true_value, false_value], [], [condition_name])
     end

[gergnz]

@lwoggardner what were/are you trying to achieve here?

[lwoggardner]

I think it is an array now because it is a List type and homogenisation of plurals behaviour. This is a relatively rare case where the actual cloudformation property has a singular name for a List property. The singular VPCZoneIdentifier adds an entry to the list. The plural VPCZoneIdentifiers should set the value (which can thus be an expression) I think there are tests that specifically test this property.

…

On Mon, 4 Nov. 2019, 10:22 pm Greg Cockburn, ***@***.***> wrote: @lwoggardner <https://github.com/lwoggardner> what were/are you trying to achieve here? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#428?email_source=notifications&email_token=AABPBICQ3B63EHSHT7V3GOTQSAAWVA5CNFSM4JIPSZ72YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEC65LSQ#issuecomment-549311946>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AABPBIHLJ4L5E25IM6566ODQSAAWVANCNFSM4JIPSZ7Q> .

[lwoggardner]

nested-arrays-spec.rb line 133

[lwoggardner]

The highlighted fnif code was update to track condition references as part of detecting missing or cyclic condition references.

[gergnz]

Thanks.

[lwoggardner]

This is actually the expected breaking change as a result of fixing #380