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Documentation Grafana Agent Flow mode Concepts Modules

Modules

You use Modules to create Grafana Agent Flow configurations that you can load as a component. Modules are a great way to parameterize a configuration to create reusable pipelines.

Modules are Grafana Agent Flow configurations which have:

• Arguments: Settings that configure a module.
• Exports: Named values that a module exposes to the consumer of the module.
• Components: Grafana Agent Flow components to run when the module is running.

You use a Module loader to load Modules into Grafana Agent Flow.

Refer to argument block and export block to learn how to define arguments and exports for a module.

Module loaders

A Module loader is a Grafana Agent Flow component that retrieves a module and runs the defined components.

Module loader components are responsible for the following functions:

• Retrieving the module source.
• Creating a Component controller for the module.
• Passing arguments to the loaded module.
• Exposing exports from the loaded module.

Module loaders are typically called module.LOADER_NAME.

Refer to Components for more information about the module loader components.

Module sources

Modules are flexible, and you can retrieve their configuration anywhere, such as:

• The local filesystem.
• An S3 bucket.
• An HTTP endpoint.

Each module loader component supports different ways of retrieving module.sources. The most generic module loader component, module.string, can load modules from the export of another Grafana Agent Flow component.

river Copy

local.file "my_module" {
  filename = "PATH_TO_MODULE"
}

module.string "my_module" {
  content = local.file.my_module.content

  arguments {
    MODULE_ARGUMENT_NAME_1 = MODULE_ARGUMENT_VALUE_1
    MODULE_ARGUMENT_NAME_2 = MODULE_ARGUMENT_VALUE_2
    // ...
  }
}

Example module

This example module manages a pipeline that filters out debug-level and info-level log lines.

river Copy

// argument.write_to is a required argument that specifies where filtered
// log lines are sent.
//
// The value of the argument is retrieved in this file with
// argument.write_to.value.
argument "write_to" {
  optional = false
}

// loki.process.filter is our component which executes the filtering, passing
// filtered logs to argument.write_to.value.
loki.process "filter" {
  // Drop all debug- and info-level logs.
  stage.match {
    selector = "{job!=\"\"} |~ \"level=(debug|info)\""
    action   = "drop"
  }

  // Send processed logs to our argument.
  forward_to = argument.write_to.value
}

// export.filter_input exports a value to the module consumer.
export "filter_input" {
  // Expose the receiver of loki.process so the module consumer can send
  // logs to our loki.process component.
  value = loki.process.filter.receiver
}

You can save the module to a file and then use it as a processing step before writing logs to Loki.

river Copy

loki.source.file "self" {
  targets = LOG_TARGETS

  // Forward collected logs to the input of our filter.
  forward_to = [module.file.log_filter.exports.filter_input]
}

module.file "log_filter" {
  filename = "/path/to/modules/log_filter.river"

  arguments {
    // Configure the filter to forward filtered logs to loki.write below.
    write_to = [loki.write.default.receiver],
  }
}

loki.write "default" {
  endpoint {
    url = "LOKI_URL"
  }
}