Template

The Template resource allows the processing of templates, outputing the result as a file.

Templating uses the Handlebars language which is Mustache template language can be found at the following location: Mustache templating language details.

Template Functions

The template resource provides custom functions that can be used inside your templates as shown in the example below.

resource "template" "consul_config" {

  source = <<-EOF

  file_content = "{{ file "./myfile.txt" }}"
  quote = {{quote something}}
  trim = {{quote (trim with_whitespace)}}

  EOF

  destination = "./consul_config/consul.hcl"
}

quote [string]

Returns the original string wrapped in quotations, quote can be used with the Go template pipe modifier.

// given the string abc

quote "abc" // would return the value "abc"

trim [string]

Removes whitespace such as carrige returns and spaces from the begining and the end of the string, can be used with the Go template pipe modifier.

// given the string abc

trim " abc " // would return the value "abc"

Attributes

Attributes are the properties of a resource that can be used to configure it.

Attribute	Description
Source source required string	Local path to the template source file ```hcl source = "myfile.txt" source = <<-EOF My inline content EOF
Destination destination required string	The destination to write the processed template to.
Variables variables map[string]any	Variables to use with the template, variables are available to be used within the template using the `go template` syntax. variables = { data_dir = "/tmp" } Given the above variables, these could be used within a template with the following convention. data_dir = "{{data_dir}}"

Computed Attributes

These attributes are computed when the config is parsed and applied, and are therefor only known at parsetime or runtime.

Attribute	Description
Meta ID meta.id string	The full ID of the resource e.g. `resource.type.name`. This is computed from the full resource path: resource "type" "name" { ... }
Meta Type meta.type string	The type of the resource. This taken from the type label of the resource definition. resource "type" "name" { ... }
Meta Name meta.name string	The name of the resource. This taken from the name label of the resource definition. resource "type" "name" { ... }

Examples

Template using HereDoc

resource "template" "consul_config" {

  source = <<-EOF
  data_dir = "{{data_dir}}"
  log_level = "DEBUG"

  datacenter = "dc1"
  primary_datacenter = "dc1"

  server = true

  bootstrap_expect = 1
  ui = true

  bind_addr = "0.0.0.0"
  client_addr = "0.0.0.0"
  advertise_addr = "10.6.0.200"

  ports {
    grpc = 8502
  }

  connect {
    enabled = true
  }
  EOF

  destination = "./consul_config/consul.hcl"

  variables = {
    data_dir = "/tmp"
  }
}

data_dir = "/tmp"
log_level = "DEBUG"

datacenter = "dc1"
primary_datacenter = "dc1"

server = true

bootstrap_expect = 1
ui = true

bind_addr = "0.0.0.0"
client_addr = "0.0.0.0"
advertise_addr = "10.6.0.200"

ports {
  grpc = 8502
}

connect {
  enabled = true
}

External Files

resource "template "consul_config" {

  source = file("./mytemplate.hcl")
  destination = "./consul_config/consul.hcl"

  variables = {
    data_dir = "/tmp"
  }
}

container "consul" {
  depends_on = ["template.consul_config"]

  image   {
    name = "consul:${variable.consul_version}"
  }

  command = ["consul", "agent", "-config-file=/config/consul.hcl"]

  volume {
    source      = resource.template.consul_config.destination
    destination = "/config/consul.hcl"
  }
}

Inline variables

resource "template" "consul_config" {

source = <<-EOF
data_dir = "${data("test")}"
log_level = "DEBUG"

datacenter = "${variable.datacenter}"

server = ${variable.server}
EOF

destination = "./consul_config/consul.hcl"

}