Replace ComplexComputedList with native array with a single ComplexComputedObject

[DanielMSchmidt]

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Description

Currently we have a very limited way of working with lists as outputs of providers and the things we support make it clear that we don't deal with a native array but something else.
To make lists behave seamlessly we need to make them first class citizens by using native arrays.

To implement this properly we need to

• return a list of Complex Elements from the getter, where
  • each native property is a token
  • each computed property is readonly
  • each complex property with computed attributes adds a put${propertyName} method to the element that takes an object with only the not-computed types as a property
• Enhance the resolve workflow to to recognize complex lists and resolve them properly
• Make the list 1 element long and throw an error if that element is used directly (i.e. through accessing the array)

This also enables us to advance the work of #925 and expose computed types as well. The current problem there is that the interface expects a getter to have the type DataKubernetesPersistentVolumeClaimSpecResource[], but in the current implementation it has (index: string) => DataKubernetesPersistentVolumeClaimSpecResources.

What this should enable

Currently inputs that are passed to a resource share the same type with references to that same attribute. For example, if we pass a string, we get back a string (which is an token encoded reference, but still appears to be a string). This is true for almost all types but not for lists. We want to achieve this for lists which contain objects (nested blocks) instead of plain values (lists of numbers or strings already return tokens encoded as a list of number / string containing the reference to that attribute).

Referencing list arguments also works in other languages than TS

When a list exists which can be set as input by the user, referencing that list does not work in other languages than TS (see: #1371). This allows the following to work:

todo: in Go referencing a list, passing it to e.g. Fn.length

Passing a reference to a list works without "fqn" hack

Example in HCL

data "aws_availability_zones" "azs" {
  state = "available"
}

resource "aws_subnet" "this" {
  # ...
  availability_zone_id = data.aws_availability_zones.azs.zone_ids[0]
}

This equivalent now works:

const azs = new DataAvailabilityZones(this, 'azs', { state: "available" })
new aws.Subnet(this, 'this', {
	availabilityZoneId: Fn.element(azs.zoneIds, 0);
	// Note: this would throw an error (as we cannot know this at synth time)
	// availabilityZoneId: azs.zoneIds[0]
})

Formerly this workaround was required (and did not work in other languages than TypeScript)

const azs = new DataAvailabilityZones(this, 'azs', { state: "available" })
new aws.Subnet(this, 'this', {
	availabilityZoneId: Fn.element(Fn.lookup(azs.fqn, 'zone_ids'), 0);
})

No more listAttribute(index) method

As passing a list reference into Fn.element() works now this type of method is not needed anymore. It was not very idiomatic anyway as it treated the output (reference) to an attribute of a resources as a different type than the input for said attribute.
Formerly listAttribute was a function (wat!?):

const item = resource.listAttribute('0'); // will be removed

Now it is a list, just like the related input:

const item = Fn.element(resource.listAttribute, 0);

References

• DataKubernetesNamespace resource is missing name field #856
• feat(lib): Complex struct attributes #925
• EKS can't get OIDC issuer #663
• check if this solves: Go: Referencing list attributes does not work #1371

[skorfmann]

Example in HCL

data "aws_availability_zones" "azs" {
  state = "available"
}

resource "aws_subnet" "this" {
  # ...
  availability_zone_id = data.aws_availability_zones.azs.zone_ids[0]
}

Isn't this just a string list and therefore a string list token already?

[ansgarm]

Isn't this just a string list and therefore a string list token already?

Whoops, you're right @skorfmann. I'll find a better example that uses a list of objects.

[github-actions]

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