Documentation Grafana Alloy Reference Components prometheus prometheus.enrich

prometheus.enrich

The prometheus.enrich component enriches metrics with additional labels from service discovery targets. It matches labels from incoming metrics against labels from discovered targets, and copies specified labels from the matched target to the metric sample. If no match occurs, the metrics pass through unchanged.

Use the target_to_metric_match argument to specify which target labels correspond to which metric labels. The map keys are target label names and the values are the corresponding metric label names. All labels in the map must match for enrichment to occur.

Usage

Alloy Copy

prometheus.enrich "<LABEL>" {
  targets = <DISCOVERY_COMPONENT>.targets

  target_to_metric_match = {
    "<TARGET_LABEL_1>" = "<METRIC_LABEL_1>",
    "<TARGET_LABEL_2>" = "<METRIC_LABEL_2>",
  }

  forward_to = [<RECEIVER_LIST>]
}

Arguments

You can use the following arguments with prometheus.enrich:

You must set at least one of target_to_metric_match or target_match_label. Setting metrics_match_label alone, without target_match_label, causes a validation error.

Blocks

The prometheus.enrich component doesn’t support any blocks. You can configure this component with arguments.

Exported fields

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

Component health

prometheus.enrich is only reported as unhealthy if given an invalid configuration. In those cases, exported fields retain their last healthy values.

Debug information

prometheus.enrich doesn’t expose any component-specific debug information.

Debug metrics

Examples

Enrich metrics from prometheus.scrape

The following example shows how the prometheus.enrich enriches incoming metrics from prometheus.scrape.default, using HTTP discovery, and forwards the results to prometheus.remote_write.default component:

Alloy Copy

discovery.http "default" {
    url = "http://network-inventory.example.com/prometheus_sd"
}

prometheus.scrape "default" {
  targets = [
    {"__address__" = "example-app:9001"},
  ]

  forward_to = [prometheus.enrich.default.receiver]
}

prometheus.enrich "default" {
	targets = discovery.http.default.targets

	target_to_metric_match = {
		"hostname" = "hostname",
	}

	forward_to = [prometheus.remote_write.default.receiver]
}

prometheus.remote_write "default" {
  endpoint {
    url = "http://mimir:9009/api/v1/push"
  }
}

Enrich metrics from prometheus.receive_http

The following example shows how the prometheus.enrich enriches incoming metrics from prometheus.receive_http.default, using file-based discovery, and forwards the results to prometheus.remote_write.default component:

Alloy Copy

discovery.file "network_devices" {
   files = ["/etc/alloy/devices.json"]
}

prometheus.receive_http "default" {
  http {
    listen_address = "0.0.0.0"
    listen_port = 9999
  }

  forward_to = [prometheus.enrich.default.receiver]
}

prometheus.enrich "default" {
    targets = discovery.file.network_devices.targets

    target_to_metric_match = {
        "hostname" = "hostname",
    }

    forward_to = [prometheus.remote_write.default.receiver]
}

prometheus.remote_write "default" {
  endpoint {
    url = "http://mimir:9009/api/v1/push"
  }
}

Multi-label matching with Kubernetes metadata

The following example enriches cAdvisor metrics with Kubernetes Pod metadata, matching on namespace, Pod, and container labels simultaneously.

Alloy Copy

discovery.kubernetes "pods" {
  role = "pod"
}

prometheus.scrape "cadvisor" {
  targets = [
    {"__address__" = "localhost:10250", "__metrics_path__" = "/metrics/cadvisor"},
  ]
  scheme = "https"

  forward_to = [prometheus.enrich.k8s_meta.receiver]
}

prometheus.enrich "k8s_meta" {
    targets = discovery.kubernetes.pods.targets

    target_to_metric_match = {
        "__meta_kubernetes_namespace"          = "namespace",
        "__meta_kubernetes_pod_name"           = "pod",
        "__meta_kubernetes_pod_container_name" = "container",
    }

    labels_to_copy = ["__meta_kubernetes_pod_node_name", "__meta_kubernetes_pod_label_app"]

    forward_to = [prometheus.remote_write.default.receiver]
}

prometheus.remote_write "default" {
  endpoint {
    url = "http://mimir:9009/api/v1/push"
  }
}

Compatible components

prometheus.enrich can accept arguments from the following components:

• Components that export Targets
• Components that export Prometheus MetricsReceiver

prometheus.enrich has exports that can be consumed by the following components:

• Components that consume Prometheus MetricsReceiver