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Command: var put

The var put command creates or updates an existing variable.

Usage

nomad var put [options] <variable spec file reference> [<key>=<value>]...
nomad var put [options] <path to store variable> [<variable spec file reference>] [<key>=<value>]...

Variable metadata and items can be supplied using a variable specification, by using command arguments, or by a combination of the two techniques. An entire variable specification can be provided to the command via standard input (stdin) by setting the first argument to "-" or from a file by using an @-prefixed path to a variable specification file. When providing variable data via stdin, you must provide the -in flag with the format of the specification, which must be either "hcl" or "json".

Items to be stored in the variable can be supplied using the specification, as a series of key-value pairs, or both. The value for a key-value pair can be a string, an @-prefixed file reference, or a '-' to get the value from stdin. Item values provided from file references or stdin are consumed as-is with no additional processing and do not require the input format to be specified.

Values supplied as command line arguments supersede values provided in any variable specification piped into the command or loaded from file. If ACLs are enabled, this command requires the variables:write capability for the destination namespace and path. See the ACL policy documentation for details.

Restrictions

Variable paths are restricted to RFC3986 URL-safe characters that don't conflict with the use of the characters @ and . in template blocks. This includes alphanumeric characters and the special characters -, _, ~, and /. Paths may be up to 128 bytes long. The following regex matches the allowed paths: ^[a-zA-Z0-9-_~/]{1,128}$

The keys for the items in a variable may contain any character, but keys containing characters outside the set of Unicode letters, Unicode digits, and the underscore (_) can not be read directly using dotted references in Nomad's template engine. Instead, they require the use of the index template function to directly access their values. This does not impact cases where the keys and values are read using the range function.

Variable items are restricted to 64KiB in size. This limit is calculated by taking the sum of the length in bytes of all of the unencrypted keys and values.

General Options

  • -address=<addr>: The address of the Nomad server. Overrides the NOMAD_ADDR environment variable if set. Defaults to http://127.0.0.1:4646.

  • -region=<region>: The region of the Nomad server to forward commands to. Overrides the NOMAD_REGION environment variable if set. Defaults to the Agent's local region.

  • -namespace=<namespace>: The target namespace for queries and actions bound to a namespace. Overrides the NOMAD_NAMESPACE environment variable if set. If set to '*', subcommands which support this functionality query all namespaces authorized to user. Defaults to the "default" namespace.

  • -no-color: Disables colored command output. Alternatively, NOMAD_CLI_NO_COLOR may be set. This option takes precedence over -force-color.

  • -force-color: Forces colored command output. This can be used in cases where the usual terminal detection fails. Alternatively, NOMAD_CLI_FORCE_COLOR may be set. This option has no effect if -no-color is also used.

  • -ca-cert=<path>: Path to a PEM encoded CA cert file to use to verify the Nomad server SSL certificate. Overrides the NOMAD_CACERT environment variable if set.

  • -ca-path=<path>: Path to a directory of PEM encoded CA cert files to verify the Nomad server SSL certificate. If both -ca-cert and -ca-path are specified, -ca-cert is used. Overrides the NOMAD_CAPATH environment variable if set.

  • -client-cert=<path>: Path to a PEM encoded client certificate for TLS authentication to the Nomad server. Must also specify -client-key. Overrides the NOMAD_CLIENT_CERT environment variable if set.

  • -client-key=<path>: Path to an unencrypted PEM encoded private key matching the client certificate from -client-cert. Overrides the NOMAD_CLIENT_KEY environment variable if set.

  • -tls-server-name=<value>: The server name to use as the SNI host when connecting via TLS. Overrides the NOMAD_TLS_SERVER_NAME environment variable if set.

  • -tls-skip-verify: Do not verify TLS certificate. This is highly not recommended. Verification will also be skipped if NOMAD_SKIP_VERIFY is set.

  • -token: The SecretID of an ACL token to use to authenticate API requests with. Overrides the NOMAD_TOKEN environment variable if set.

Put Options

  • -check-index (int: <unset>): If set, the variable is only acted upon if the server-side version's index matches the provided value. When a variable specification contains a modify index, that modify index is used as the check-index for the check-and-set operation and can be overridden using this flag.

  • -force: Perform this operation regardless of the state or index of the variable on the server-side.

  • -in (enum: hcl | json): Parser to use for data supplied via standard input or when the variable specification's type can not be known using the file extension. Defaults to "json".

  • -out (enum: go-template | hcl | json | none | table): Format to render created or updated variable. Defaults to "none" when stdout is a terminal and "json" when the output is redirected.

  • -template (string: ""): Template to render output with. Required when format is "go-template", invalid for other formats.

  • -verbose: Provides additional information via standard error to preserve standard output (stdout) for redirected output.

Examples

Writes the data to the path "secret/creds":

$ nomad var put secret/creds passcode=my-long-passcode

The data can also be consumed from a file on disk by prefixing with the "@" symbol. For example, you can store a variable using a specification created with the nomad var init command.

$ nomad var put secret/foo @spec.nv.json

Or it can be read from standard input using the "-" symbol:

$ echo "abcd1234" | nomad var put secret/foo bar=-
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