Fancy.tf

################################################
# Lambda Resources Option 3 - Multiple Lambdas
################################################
#In this scenario the Lambda is zipped and upload outside of the terraform execution
resource "aws_lambda_function" "test_lambda" {
  s3_bucket = var.code-bucket 
  s3_key = local.signedSourceList[index(local.trimPrefix, "lambda")]
  # ^ Returns "signed/lambda-3ed11736-6655-4448-935d-659cd0428b90.zip"
  ....
  ....
}

resource "aws_lambda_function" "test_lambda_2" {
  s3_bucket = var.code-bucket
  s3_key        = local.signedSourceList[index(local.trimPrefix, "postBooks")]
  # ^ Returns "signed/postBooks-fa44bbee-9f5b-455d-7cfd-14450e4679d.zip"
  ....
  ....
}

data "aws_s3_bucket_objects" "signedLambdas" {
  bucket = var.code-bucket
  prefix = "signed/"
}

locals {
  signedSourceList = data.aws_s3_bucket_objects.signedLambdas.keys
  lambdaSource     = try(local.signedSourceList[0], null)
  trimPrefix =  [ for item in  local.signedSourceList :  split("-", trimprefix(item, "signed/"))[0]]
}