[Bug]: aws_lambda_function: perpetual drift in log levels

[Michagogo]

Terraform Core Version

1.6.6

AWS Provider Version

5.32.1

Affected Resource(s)

aws_lambda_function

Expected Behavior

The new logging_config block contains optional arguments {application,system}_log_level. When those arguments are left undefined, the default (or existing, presumably, in case of manual change, import, etc.) should be ignored/left as is, if that’s a possibility. In any case, a second consecutive terraform apply should, as always, return no changes.

Actual Behavior

On every apply, the plan will always propose the resource to be updated in-place, such as the following:

~ logging_config {
    - application_log_level = "INFO" -> null
    - system_log_level     = "INFO" -> null
       # (2 unchanged attributes hidden)
}

Relevant Error/Panic Output Snippet

No response

Terraform Configuration Files

resource "aws_iam_role" "lambda" {
  # insert applicable policies here
}

resource "aws_cloudwatch_log_group" "lambda" {}

data "archive_file" "null" {
  type = "zip"
  output_path = "null.zip"
  source_content = "pass"
  source_content_filename = "null.py"
}

resource "aws_lambda_function" "test" {
  function_name = "test"
  role          = aws_iam_role.lambda.arn
  filename      = "null.zip"
  handler      = "null"
  runtime      = "python3.12"
  logging_config {
    log_format = "JSON"
    log_group  = aws_cloudwatch_log_group.lambda.id
  }
}

Steps to Reproduce

1. terraform apply
2. terraform apply

Debug Output

No response

Panic Output

No response

Important Factoids

No response

References

Relates #35050

Would you like to implement a fix?

No

[github-actions]

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[github-actions]

This functionality has been released in v5.36.0 of the Terraform AWS Provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

For further feature requests or bug reports with this functionality, please create a new GitHub issue following the template. Thank you!

[github-actions]

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