org.forgerock.monitoring.http

Class PrometheusHandler

java.lang.Object

org.forgerock.monitoring.http.PrometheusHandler

All Implemented Interfaces:

Handler

public final class PrometheusHandler
extends Object
implements Handler

An HTTP Handler from which Prometheus can scrap monitoring information.

Field Summary

Fields

Modifier and Type	Field and Description
static List<String>	SUPPORTED_HTTP_METHODS List of HTTP methods supported by a Prometheus Handler.

Method Summary

Modifier and Type	Method and Description
Promise<Response,NeverThrowsException>	handle(Context context, Request request) Returns a Promise representing the asynchronous Response of the given request.
static PrometheusHandler	prometheusHandler(String metricPrefix, Supplier<MeterRegistry> meterRegistrySupplier) Returns a new Prometheus Handler.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

SUPPORTED_HTTP_METHODS

public static final List<String> SUPPORTED_HTTP_METHODS

List of HTTP methods supported by a Prometheus Handler.

Method Detail

prometheusHandler

public static PrometheusHandler prometheusHandler(String metricPrefix,
                                                  Supplier<MeterRegistry> meterRegistrySupplier)

Returns a new Prometheus Handler.

Parameters:

metricPrefix - The prefix that will be prepended before each metrics. Ideally this will be the product specific prefix.

meterRegistrySupplier - A Supplier of the MetricRegistry which will be used to collect metrics to include in HTTP response sent by this PrometheusHandler.

Returns:

a new PrometheusHandler

handle

public Promise<Response,NeverThrowsException> handle(Context context,
                                                     Request request)

Description copied from interface: Handler

Returns a Promise representing the asynchronous Response of the given request. If any (asynchronous) processing goes wrong, the promise still contains a Response (probably from the 4xx or 5xx status code family).

A handler that doesn't hand-off the processing to another downstream handler is responsible for creating the response.

The returned Promise contains the response returned from the server as-is. This is responsibility of the handler to produce the appropriate error response (404, 500, ...) in case of processing error.

Note: As of Promise 2.0 implementation, it is not permitted to throw any runtime exception here. Doing so produce unexpected behaviour (most likely a server-side hang of the processing thread).

Specified by:

handle in interface Handler

Parameters:

context - The request context.

request - The request.

Returns:

A Promise representing the response to be returned to the caller.