Documentation Grafana Cloud Instrument and send data Grafana Alloy Reference Components loki loki.source.heroku

loki.source.heroku

loki.source.heroku listens for Heroku messages over TCP connections and forwards them to other loki.* components.

The component starts a new heroku listener for the given listener block and fans out incoming entries to the list of receivers in forward_to.

Before using loki.source.heroku, Heroku should be configured with the URL where Alloy will be listening. Follow the steps in Heroku HTTPS Drain docs for using the Heroku CLI with a command like the following:

shell Copy

heroku drains:add [http|https]://HOSTNAME:PORT/heroku/api/v1/drain -a HEROKU_APP_NAME

Multiple loki.source.heroku components can be specified by giving them different labels.

Usage

alloy Copy

loki.source.heroku "LABEL" {
    http {
        listen_address = "LISTEN_ADDRESS"
        listen_port    = LISTEN_PORT
    }
    forward_to = RECEIVER_LIST
}

Arguments

loki.source.heroku supports the following arguments:

The relabel_rules field can make use of the rules export value from a loki.relabel component to apply one or more relabeling rules to log entries before they’re forwarded to the list of receivers in forward_to.

Blocks

The following blocks are supported inside the definition of loki.source.heroku:

http

The http block configures the HTTP server.

You can use the following arguments to configure the http block. Any omitted fields take their default values.

grpc

The grpc block configures the gRPC server.

You can use the following arguments to configure the grpc block. Any omitted fields take their default values.

Labels

The labels map is applied to every message that the component reads.

The following internal labels all prefixed with __ are available but will be discarded if not relabeled:

• __heroku_drain_host
• __heroku_drain_app
• __heroku_drain_proc
• __heroku_drain_log_id

All url query params will be translated to __heroku_drain_param_<name>

If the X-Scope-OrgID header is set it will be translated to __tenant_id__

Exported fields

loki.source.heroku does not export any fields.

Component health

loki.source.heroku is only reported as unhealthy if given an invalid configuration.

Debug information

loki.source.heroku exposes some debug information per Heroku listener:

• Whether the listener is currently running.
• The listen address.

Debug metrics

• loki_source_heroku_drain_entries_total (counter): Number of successful entries received by the Heroku target.
• loki_source_heroku_drain_parsing_errors_total (counter): Number of parsing errors while receiving Heroku messages.

Example

This example listens for Heroku messages over TCP in the specified port and forwards them to a loki.write component using the Heroku timestamp.

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loki.source.heroku "local" {
    http {
        listen_address = "0.0.0.0"
        listen_port    = 4040
    }
    use_incoming_timestamp = true
    labels                 = {component = "loki.source.heroku"}
    forward_to             = [loki.write.local.receiver]
}

loki.write "local" {
    endpoint {
        url = "loki:3100/api/v1/push"
    }
}

When using the default http block settings, the server listen for new connection on port 8080.

alloy Copy

loki.source.heroku "local" {
    use_incoming_timestamp = true
    labels                 = {component = "loki.source.heroku"}
    forward_to             = [loki.write.local.receiver]
}

loki.write "local" {
    endpoint {
        url = "loki:3100/api/v1/push"
    }
}

Compatible components

loki.source.heroku can accept arguments from the following components:

• Components that export Loki LogsReceiver