Data sources that return lists throw an error when target resources do not exist

[YutaHig]

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• The resources and data sources in this provider are generated from the CloudFormation schema, so they can only support the actions that the underlying schema supports. For this reason submitted bugs should be limited to defects in the generation and runtime code of the provider. Customizing behavior of the resource, or noting a gap in behavior are not valid bugs and should be submitted as enhancements to AWS via the CloudFormation Open Coverage Roadmap.

Terraform CLI and Terraform AWS Cloud Control Provider Version

Terraform v1.11.0
on darwin_arm64

• provider [registry.terraform.io/hashicorp/awscc](http://registry.terraform.io/hashicorp/awscc) v1.30.0

Affected Resource(s)

• data.awscc_xxxxxs

All data sources which return list.

Terraform Configuration Files

terraform {
  required_providers {
    awscc = {
      source  = "hashicorp/awscc"
      version = "~> 1.30.0"
    }
  }
}

provider "awscc" {
  region = "ap-northeast-1"
}

# Any data sources that retrieves resources not exist in the target AWS account.
data "awscc_amplify_apps" "all" {}

Debug Output

Panic Output

Expected Behavior

A data source that returns multiple resources will return an empty list if the target resource does not exist.

For example, in the case of the aws provider, it behaves as follows:

# Any data sources that retrieves resources not exist in the target AWS account.
data "aws_db_instances" "all" {}

output "aws_db_instances" {
  value = data.aws_db_instances.all
}

❯ terraform apply --auto-approve
data.aws_db_instances.all: Reading...
data.aws_db_instances.all: Read complete after 0s [id=ap-northeast-1]

Changes to Outputs:
  + aws_db_instances = {
      + filter               = null
      + id                   = "ap-northeast-1"
      + instance_arns        = []
      + instance_identifiers = []
      + tags                 = null
    }

You can apply this plan to save these new output values to the Terraform state, without changing any real infrastructure.

Apply complete! Resources: 0 added, 0 changed, 0 destroyed.

Outputs:

aws_instances = {
  "filter" = toset(null) /* of object */
  "id" = "ap-northeast-1"
  "instance_arns" = tolist([])
  "instance_identifiers" = tolist([])
  "tags" = tomap(null) /* of string */
}

Actual Behavior

If the data source's target does not exist in the target AWS account, it will result in an error.
So it is not possible to use the data resource's results for conditional branching.

❯ terraform apply
data.awscc_amplify_apps.all: Reading...
╷
│ Error: AWS SDK Go Service Operation Unsuccessful
│ 
│   with data.awscc_amplify_apps.all,
│   on terraform.tf line 5, in data "awscc_amplify_apps" "all":
│   5: data "awscc_amplify_apps" "all" {}
│ 
│ Calling CloudControl service ListResources operation returned: Empty result

Steps to Reproduce

1. terraform plan

Important Factoids

References

• fix: pagination on plural datasources #2208
• f2b58f1#diff-454647fad25d35c5a2d2eec06abe0511ab8a73b1d16e36d172ef788aced297b4L35