Unsupported functions in template file

Hello!

Looks like there are unsupported functions in template file.

Documentation says "The template may also use any other function available in the Terraform language, except that recursive calls to templatefile are not permitted" but i found out that neither 'regex' nor 'regexall' are in fact supported:

Terraform Version

me@my-mac ~/Code/consul-vault/app/staging $ terraform -v Terraform v0.12.24

provider.null v2.1.2
provider.template v2.1.2
provider.vsphere v1.17.2

Affected Resource(s)

data.template_file

Terraform Configuration Files

data "template_file" "consul_config" {
  template = file("${path.module}/consul_config.json.tmpl")
  count = length(var.ipv4_addresses)

  vars = {
    node_name         = format("${var.vm_prefix}-%02d", count.index +1)
    datacenter        = "dc"
    svc_domain        = "service.local"
    bind_addr         = var.ipv4_addresses[count.index]
    advertise_addr    = var.ipv4_addresses[count.index]
    client_addr       = "0.0.0.0"
    bootstrap_expect  = length(var.ipv4_addresses)
    retry_join        = jsonencode(var.ipv4_addresses)
  }
}

Template file

{
%{ if regex(".+consul.+", node_name) }
  "server": true,
  "domain": "${svc_domain}",
  "bootstrap_expect": ${bootstrap_expect},
  "ui": true,
%{ endif ~}
  "node_name": "${node_name}",
  "datacenter": "${datacenter}",
  "data_dir": "/consul/data",
  "bind_addr": "${bind_addr}",
  "advertise_addr": "${advertise_addr}",
  "client_addr": "${client_addr}",
  "retry_join": ${retry_join},
  "log_level": "INFO",
  "acl_enforce_version_8": false
}

Panic Output

Error: failed to render : :2,7-12: Call to unknown function; There is no function named "regex".

on ../../modules/provision.tf line 1, in data "template_file" "consul_config": 1: data "template_file" "consul_config" {

Similar error is produced if i try to use %{ if length(regexall(".+consul.+", node_name)) > 0 } in template:

Error: failed to render : :2,14-22: Call to unknown function; There is no function named "regexall".

on ../../modules/provision.tf line 1, in data "template_file" "consul_config": 1: data "template_file" "consul_config" {

Expected Behavior

As documentation implies all terraform functions should be supported in template file except recursive calls to templatefile

Actual Behavior

Template fails to render

Steps to Reproduce

Create a template using regex or regexall function in it
run terraform apply

hashicorp / terraform-provider-template