Support for ignoring changes to size_in_bytes attribute in aws_efs_file_system

Is your request related to a new offering from AWS?

No 🛑, this request is not related to a new offering from AWS, but rather to a common behavior of AWS EFS where the size_in_bytes attribute can change outside of Terraform's management, causing unnecessary noise in terraform plan output.

Is your request related to a problem? Please describe.

I'm always frustrated when every time someone opens a PR, and we run terraform plan, it shows changes in the EFS size_in_bytes like it's a change in the PR, even though the actual filesystem configuration hasn't changed. This creates confusion and makes it harder to review the actual changes introduced by the PR.

Describe the solution you'd like.

I would like the terraform-aws-modules/efs/aws module to support an option to ignore changes to the size_in_bytes attribute in the aws_efs_file_system resource. This can be implemented by allowing users to specify a lifecycle block configuration within the module that would pass through to the underlying aws_efs_file_system resource.

For example, the module could expose a variable such as ignore_size_in_bytes_changes that, when set to true, would automatically add the following lifecycle configuration to the aws_efs_file_system resource:

lifecycle {
  ignore_changes = [
    size_in_bytes,
  ]
}

Describe alternatives you've considered.

As an alternative, I have considered creating a wrapper module to simulate ignoring changes to the size_in_bytes attribute using a null_resource with custom triggers. However, this approach is not ideal as it adds complexity and doesn't directly address the issue at the resource level.

Another alternative is to manually ignore these changes in the terraform plan output, but this is error-prone and not a scalable solution for larger teams or automated CI/CD pipelines.

Additional context

The ability to ignore certain attributes from the terraform plan output is crucial for teams to review and understand infrastructure changes accurately. Supporting this feature within the module would greatly enhance the usability and reduce potential confusion during code reviews.

terraform-aws-modules / terraform-aws-efs