How do I escape true/false in terraform?

Question

I need to pass the word true or false to a data template file in terraform. However, if I try to provide the value, it comes out 0 or 1 due to interpolation syntax. I tried doing \\true\\ as recommended in https://www.terraform.io/docs/configuration/interpolation.html, however that results in \true\, which obviously isn't right. Same with \\false\\ = \false\

To complicate matters, I also have a scenario where I need to pass it the value of a variable, which can either equal true or false. Any ideas?

# control whether to enable REST API and set other port defaults
data "template_file" "master_spark_defaults" {
  template = "${file("${path.module}/templates/spark/spark-    defaults.conf")}"

  vars = {
    spark_server_port   = "${var.application_port}"
    spark_driver_port   = "${var.spark_driver_port}"
    rest_port           = "${var.spark_master_rest_port}"
    history_server_port = "${var.history_server_port}"
    enable_rest         = "${var.spark_master_enable_rest}"
  }
}

var.spark_master_enable_rest can be either true or false. I tried setting the variable as "\\${var.spark_master_enable_rest}\\" but again this resulted in either \true\ or \false\

Edit 1:

Here is the relevant portion of conf file in question:

spark.ui.port ${spark_server_port}
# set to default worker random number.
spark.driver.port ${spark_driver_port}

spark.history.fs.logDirectory /var/log/spark
spark.history.ui.port ${history_server_port}

spark.worker.cleanup.enabled true
spark.worker.cleanup.appDataTtl 86400

spark.master.rest.enabled ${enable_rest}
spark.master.rest.port ${rest_port}

Answer 1

I ended up creating a cloud-config script to find/replace the 0/1 in the file:

  part {
    content_type = "text/x-shellscript"

    content = <<SCRIPT
    #!/bin/sh
    sed -i.bak -e '/spark.master.rest.enabled/s/0/false/' -e '/spark.master.rest.enabled/s/1/true/' /opt/spark/conf/spark-defaults.conf
SCRIPT
  }