aws_s3_bucket_object

data "aws_s3_bucket_object" "${lambda}" {
    bucket = "my-lambda-functions"
    key = "hello-world.zip"
}

resource "aws_iam_role" "iam_for_lambda" {
    name = "iam_for_lambda"
    assume_role_policy = <<EOF
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Action": "sts:AssumeRole",
            "Principal": {
            "Service": "lambda.amazonaws.com"
        },
            "Effect": "Allow",
            "Sid": ""
        }
    ]
}
EOF
}

resource "aws_lambda_function" "test_lambda" {
    s3_bucket = "\${data.aws_s3_bucket_object.${lambda}.bucket}"
    s3_key = "\${data.aws_s3_bucket_object.${lambda}.key}"
    s3_object_version = "\${data.aws_s3_bucket_object.${lambda}.version_id}"
    function_name = "lambda_function_name"
    role = "\${aws_iam_role.iam_for_lambda.arn}"
    handler = "exports.test"
}