--- layout: "language" page_title: "templatefile - Functions - Configuration Language" sidebar_current: "docs-funcs-file-templatefile" description: |- The templatefile function reads the file at the given path and renders its content as a template. --- # `templatefile` Function `templatefile` reads the file at the given path and renders its content as a template using a supplied set of template variables. ```hcl templatefile(path, vars) ``` The template syntax is the same as for [string templates](/docs/language/expressions/strings.html#string-templates) in the main Terraform language, including interpolation sequences delimited with `${` ... `}`. This function just allows longer template sequences to be factored out into a separate file for readability. The "vars" argument must be a map. Within the template file, each of the keys in the map is available as a variable for interpolation. The template may also use any other function available in the Terraform language, except that recursive calls to `templatefile` are not permitted. Variable names must each start with a letter, followed by zero or more letters, digits, or underscores. Strings in the Terraform language are sequences of Unicode characters, so this function will interpret the file contents as UTF-8 encoded text and return the resulting Unicode characters. If the file contains invalid UTF-8 sequences then this function will produce an error. This function can be used only with files that already exist on disk at the beginning of a Terraform run. Functions do not participate in the dependency graph, so this function cannot be used with files that are generated dynamically during a Terraform operation. ## Examples ### Lists Given a template file `backends.tpl` with the following content: ``` %{ for addr in ip_addrs ~} backend ${addr}:${port} %{ endfor ~} ``` The `templatefile` function renders the template: ``` > templatefile("${path.module}/backends.tpl", { port = 8080, ip_addrs = ["10.0.0.1", "10.0.0.2"] }) backend 10.0.0.1:8080 backend 10.0.0.2:8080 ``` ### Maps Given a template file `config.tmpl` with the following content: ``` %{ for config_key, config_value in config } set ${config_key} = ${config_value} %{ endfor ~} ``` The `templatefile` function renders the template: ``` > templatefile( "${path.module}/config.tmpl", { config = { "x" = "y" "foo" = "bar" "key" = "value" } } ) set foo = bar set key = value set x = y ``` ### Generating JSON or YAML from a template If the string you want to generate will be in JSON or YAML syntax, it's often tricky and tedious to write a template that will generate valid JSON or YAML that will be interpreted correctly when using lots of individual interpolation sequences and directives. Instead, you can write a template that consists only of a single interpolated call to either [`jsonencode`](./jsonencode.html) or [`yamlencode`](./yamlencode.html), specifying the value to encode using [normal Terraform expression syntax](/docs/language/expressions/index.html) as in the following examples: ``` ${jsonencode({ "backends": [for addr in ip_addrs : "${addr}:${port}"], })} ``` ``` ${yamlencode({ "backends": [for addr in ip_addrs : "${addr}:${port}"], })} ``` Given the same input as the `backends.tmpl` example in the previous section, this will produce a valid JSON or YAML representation of the given data structure, without the need to manually handle escaping or delimiters. In the latest examples above, the repetition based on elements of `ip_addrs` is achieved by using a [`for` expression](/docs/language/expressions/for.html) rather than by using [template directives](/docs/language/expressions/strings.html#directives). ```json {"backends":["10.0.0.1:8080","10.0.0.2:8080"]} ``` If the resulting template is small, you can choose instead to write `jsonencode` or `yamlencode` calls inline in your main configuration files, and avoid creating separate template files at all: ```hcl locals { backend_config_json = jsonencode({ "backends": [for addr in ip_addrs : "${addr}:${port}"], }) } ``` For more information, see the main documentation for [`jsonencode`](./jsonencode.html) and [`yamlencode`](./yamlencode.html). ## Related Functions * [`file`](./file.html) reads a file from disk and returns its literal contents without any template interpretation.