argument.md

---

title: argument

---

argument block

argument is an optional configuration block used to specify parameterized input to a [Module][Modules]. argument blocks must be given a label which determines the name of the argument.

The argument block may not be specified in the main configuration file given to Grafana Agent Flow.

[Modules]: {{< relref "../../concepts/modules.md" >}}

Example

argument "ARGUMENT_NAME" {}

Arguments

NOTE: For clarity, "argument" in this section refers to arguments which can be given to the argument block. "Module argument" refers to the argument being defined for a module, determined by the label of the argument block.

The following arguments are supported:

Name	Type	Description	Default	Required
optional	bool	Whether the argument may be omitted.	false	no
comment	string	Description for the argument.	false	no
default	any	Default value for the argument.	null	no

By default, all module arguments are required. The optional argument can be used to mark the module argument as optional. When optional is true, the initial value for the module argument is specified by default.

Exported fields

The following fields are exported and can be referenced by other components:

Name	Type	Description
value	any	The current value of the argument.

The module loader is responsible for determining the values for arguments. Components in a module may use argument.ARGUMENT_NAME.value to retrieve the value provided by the module loader.

Example

This example creates a module where agent metrics are collected. Collected metrics are then forwarded to the argument specified by the loader:

argument "metrics_output" {
  optional = false
  comment  = "Where to send collected metrics."
}

prometheus.scrape "selfmonitor" {
  targets = [{
    __address__ = "127.0.0.1:12345",
  }]

  forward_to = [argument.metrics_output.value]
}