---
page_title: consul function reference
description: The `consul` function retrieves secrets from HashiCorp Consul KV stores. Learn how to use the `consul` function in Packer templates.
---

# `consul_key` Function

[Consul](https://www.consul.io/) keys can be used within your template using the
`consul_key` function.

You can either use this function in a locals block or directly inline where you
want to use the value.

```hcl
locals {
  my_version = "${consul_key("myservice/version")}"
}

source "null" "first-example" {
  communicator = "none"
}

build {
  name = "my-build-name"
  sources = ["null.first-example"]

  provisioner "shell-local" {
    environment_vars = ["TESTVAR=${build.PackerRunUUID}"]
    inline = ["echo my_version is '${local.my_version}'",
              "echo version is '${consul_key("myservice/version")}'."]
  }
}
```

This will load the key stored at the path `myservice/version` from consul.

The configuration for consul (address, tokens, ...) must be specified as
environment variables, as specified in the
[Documentation](/consul/commands#environment-variables).
