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template Template: template_file docs-template-datasource-file Renders a template from a file.

template_file

Renders a template from a file.

Example Usage

Option 1: From a file:

Reference the template path:

data "template_file" "init" {
  template = "${file("${path.module}/init.tpl")}"

  vars {
    consul_address = "${aws_instance.consul.private_ip}"
  }
}

Inside the file, reference the variable as such:

#!/bin/bash

echo "CONSUL_ADDRESS = ${consul_address}" > /tmp/iplist

Option 2: Inline:

data "template_file" "init" {
  template = "$${consul_address}:1234"

  vars {
    consul_address = "${aws_instance.consul.private_ip}"
  }
}

Argument Reference

The following arguments are supported:

  • template - (Required) The contents of the template. These can be loaded from a file on disk using the file() interpolation function.

  • vars - (Optional) Variables for interpolation within the template. Note that variables must all be primitives. Direct references to lists or maps will cause a validation error.

The following arguments are maintained for backwards compatibility and may be removed in a future version:

  • filename - Deprecated, please use template instead. The filename for the template. Use path variables to make this path relative to different path roots.

Attributes Reference

The following attributes are exported:

  • template - See Argument Reference above.
  • vars - See Argument Reference above.
  • rendered - The final rendered template.

Template Syntax

The syntax of the template files is the same as standard interpolation syntax, but you only have access to the variables defined in the vars section.

To access interpolations that are normally available to Terraform configuration (such as other variables, resource attributes, module outputs, etc.) you'll have to expose them via vars as shown below:

data "template_file" "init" {
  # ...

  vars {
    foo  = "${var.foo}"
    attr = "${aws_instance.foo.private_ip}"
  }
}

Inline Templates

Inline templates allow you to specify the template string inline without loading a file. An example is shown below:

data "template_file" "init" {
  template = "$${consul_address}:1234"

  vars {
    consul_address = "${aws_instance.consul.private_ip}"
  }
}

-> Important: Template variables in an inline template (such as consul_address above) must be escaped with a double-$. Unescaped interpolations will be processed by Terraform normally prior to executing the template.

An example of mixing escaped and non-escaped interpolations in a template:

variable "port" { default = 80 }

data "template_file" "init" {
  template = "$${foo}:${var.port}"

  vars {
    foo = "${count.index}"
  }
}

In the above example, the template is processed by Terraform first to turn it into: ${foo}:80. After that, the template is processed as a template to interpolate foo.

In general, you should use template variables in the vars block and try not to mix interpolations. This keeps it understandable and has the benefit that you don't have to change anything to switch your template to a file.