let aws_serverless_functions = Resources.*[ Type == 'AWS::Serverless::Function' ]

rule KEY_COMPLIANCE_CHECK when %aws_serverless_functions !empty {
  %aws_serverless_functions.Properties.Tags is_struct
  %aws_serverless_functions.Properties.Tags !empty

  # check the key ignoring capitalization/casing
  let key = %aws_serverless_functions.Properties.Tags[ keys == /^(?i)first([-|_])?name$/ ]

  # check the value
  some %aws_serverless_functions.Properties.Tags.* == /^(?i)prod$/

  %key !empty
}