---
layout: docs
page_title: Nomad Variable Specification
description: Learn about Nomad's Variable specification.
---

# Nomad Variable Specification

[Nomad Variables][nv] may be specified as HCL files and submitted by the
[`nomad var put`][var-put] CLI command.

Unlike [Job specifications][jobspecs], Nomad Variables specifications do *not*
support HCL2 features like functions.

Example variable specification generated by [`nomad var init`][var-init]:

```hcl
# A variable path can be specified in the specification file
# and will be used when writing the variable without specifying a
# path in the command or when writing JSON directly to the `/var/`
# HTTP API endpoint
# path = "path/to/variable"

# The Namespace to write the variable can be included in the specification. This
# value can be overridden by specifying the "-namespace" flag on the "put"
# command.
# namespace = "default"

# The items map is the only strictly required part of a variable
# specification, since path and namespace can be set via other means.
# It contains the sensitive material to encrypt and store as a Nomad
# variable. The entire items map is encrypted and decrypted as a
# single unit.

# REMINDER: While keys in the items map can contain dots, using them
# in templates is easier when they do not. As a best practice, avoid
# dotted keys when possible.
items {
  key1 = "value 1"
  key2 = "value 2"
}
```

Example usage if the above is in a file named `spec.nv.hcl`:

```shell-session
$ nomad var put -in hcl some/path @spec.nv.hcl
```

## Variable Specification Parameters

- `path` `(string: <optional>)` - The path to the variable being defined. If
  empty it must be specified on the command line.

- `namespace` `(string: <optional>)` - The namespace of the variable. May be
  overridden by the `-namespace` command line flag or `NOMAD_NAMESPACE`
  environment variable.

- `items` `(object: <required>)` - Object of keys and values to set. Must be
  strings.

See [Variable Restrictions][var-restrict] for details on `path` and `items`
name restrictions.

[nv]: /nomad/docs/concepts/variables
[var-init]: /nomad/docs/commands/var/init
[var-put]: /nomad/docs/commands/var/put
[jobspecs]: /nomad/docs/job-specification
[var-restrict]: /nomad/docs/commands/var/put#restrictions
