.github/workflows/nodejs.yml

@@ -16,15 +16,15 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        node-version: [10.x, 12.x, 14.x, 16.x]
+        node-version: [10.x, 12.x, 14.x, 16.x, 17.x, 18.x]
         os: [ubuntu-latest, windows-latest, macOS-latest]
 
     runs-on: ${{ matrix.os }}
 
     steps:
       - uses: actions/checkout@v2
       - name: Use Node.js ${{ matrix.node-version }}
-        uses: actions/setup-node@v2-beta
+        uses: actions/setup-node@v2
         with:
           node-version: ${{ matrix.node-version }}
       - name: Restore dependencies cache

CHANGELOG.md

@@ -11,14 +11,42 @@ project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Changed
 
-- changed: typedef for pushgateway to reflect js implementation.
+### Added
+
+## [14.1.0] - 2022-08-23
+
+### Changed
+
+- types: converted all the generic Metric types to be optional
+
+- The `done()` functions returned by `gauge.startTimer()` and
+  `summary.startTimer()` now return the timed duration. Histograms already had
+  this behavior.
+
+- types: fixed type for `registry.getMetricsAsArray()`
 
-  Pushgateway's typedef were missing promise return type. That was
-  causing vscode to think that push/pushAdd and delete didn't promise
-  resulting in incorrect behavior.
+- Improve performance of `gague.inc()` and `gauge.dec()` by calling `hashObject()` once.
 
 ### Added
 
+- The `processResources` metric was added, which keeps a track of all sorts of
+  active resources. It consists of the following gauges:
+
+  - `nodejs_active_resources` - Number of active resources that are currently
+    keeping the event loop alive, grouped by async resource type.
+  - `nodejs_active_resources_total` - Total number of active resources.
+    It is supposed to provide the combined result of the `processHandles` and
+    `processRequests` metrics along with information about any other types of
+    async resources that these metrics do not keep a track of (like timers).
+
+- Support gzipped pushgateway requests
+
+## [14.0.1] - 2021-11-02
+
+### Changed
+
+- changed: typedef for pushgateway to reflect js implementation.
+
 ## [14.0.0] - 2021-09-18
 
 ### Breaking

README.md

@@ -310,7 +310,7 @@ const gauge = new client.Gauge({
 gauge.set({ method: 'GET', statusCode: '200' }, 100);
 // 2nd version: Same effect as above
 gauge.labels({ method: 'GET', statusCode: '200' }).set(100);
-// 3nd version: And again the same effect as above
+// 3rd version: And again the same effect as above
 gauge.labels('GET', '200').set(100);
 ```
 

index.d.ts

@@ -34,7 +34,7 @@ export class Registry {
 	/**
 	 * Get all metrics as objects
 	 */
-	getMetricsAsArray(): Promise<metric[]>;
+	getMetricsAsArray(): metric[];
 
 	/**
 	 * Remove a single metric
@@ -116,7 +116,7 @@ export class AggregatorRegistry extends Registry {
 /**
  * General metric type
  */
-export type Metric<T extends string> =
+export type Metric<T extends string = string> =
 	| Counter<T>
 	| Gauge<T>
 	| Summary<T>
@@ -163,7 +163,7 @@ export interface CounterConfiguration<T extends string>
 /**
  * A counter is a cumulative metric that represents a single numerical value that only ever goes up
  */
-export class Counter<T extends string> {
+export class Counter<T extends string = string> {
 	/**
 	 * @param configuration Configuration when creating a Counter metric. Name and Help is required.
 	 */
@@ -232,7 +232,7 @@ export interface GaugeConfiguration<T extends string>
 /**
  * A gauge is a metric that represents a single numerical value that can arbitrarily go up and down.
  */
-export class Gauge<T extends string> {
+export class Gauge<T extends string = string> {
 	/**
 	 * @param configuration Configuration when creating a Gauge metric. Name and Help is mandatory
 	 */
@@ -284,11 +284,13 @@ export class Gauge<T extends string> {
 	setToCurrentTime(labels?: LabelValues<T>): void;
 
 	/**
-	 * Start a timer where the gauges value will be the duration in seconds
+	 * Start a timer. Calling the returned function will set the gauge's value
+	 * to the observed duration in seconds.
 	 * @param labels Object with label keys and values
-	 * @return Function to invoke when timer should be stopped
+	 * @return Function to invoke when timer should be stopped. The value it
+	 * returns is the timed duration.
 	 */
-	startTimer(labels?: LabelValues<T>): (labels?: LabelValues<T>) => void;
+	startTimer(labels?: LabelValues<T>): (labels?: LabelValues<T>) => number;
 
 	/**
 	 * Return the child for given labels
@@ -348,10 +350,12 @@ export namespace Gauge {
 		setToCurrentTime(): void;
 
 		/**
-		 * Start a timer where the gauges value will be the duration in seconds
-		 * @return Function to invoke when timer should be stopped
+		 * Start a timer. Calling the returned function will set the gauge's value
+		 * to the observed duration in seconds.
+		 * @return Function to invoke when timer should be stopped. The value it
+		 * returns is the timed duration.
 		 */
-		startTimer(): (labels?: LabelValues<T>) => void;
+		startTimer(): (labels?: LabelValues<T>) => number;
 	}
 }
 
@@ -364,7 +368,7 @@ export interface HistogramConfiguration<T extends string>
 /**
  * A histogram samples observations (usually things like request durations or response sizes) and counts them in configurable buckets
  */
-export class Histogram<T extends string> {
+export class Histogram<T extends string = string> {
 	/**
 	 * @param configuration Configuration when creating the Histogram. Name and Help is mandatory
 	 */
@@ -383,9 +387,11 @@ export class Histogram<T extends string> {
 	observe(labels: LabelValues<T>, value: number): void;
 
 	/**
-	 * Start a timer where the value in seconds will observed
+	 * Start a timer. Calling the returned function will observe the duration in
+	 * seconds in the histogram.
 	 * @param labels Object with label keys and values
-	 * @return Function to invoke when timer should be stopped
+	 * @return Function to invoke when timer should be stopped. The value it
+	 * returns is the timed duration.
 	 */
 	startTimer(labels?: LabelValues<T>): (labels?: LabelValues<T>) => number;
 
@@ -435,9 +441,11 @@ export namespace Histogram {
 		observe(value: number): void;
 
 		/**
-		 * Start a timer where the value in seconds will observed
+		 * Start a timer. Calling the returned function will observe the
+		 * duration in seconds in the histogram.
 		 * @param labels Object with label keys and values
-		 * @return Function to invoke when timer should be stopped
+		 * @return Function to invoke when timer should be stopped. The value it
+		 * returns is the timed duration.
 		 */
 		startTimer(): (labels?: LabelValues<T>) => void;
 	}
@@ -462,7 +470,7 @@ export interface SummaryConfiguration<T extends string>
 /**
  * A summary samples observations
  */
-export class Summary<T extends string> {
+export class Summary<T extends string = string> {
 	/**
 	 * @param configuration Configuration when creating Summary metric. Name and Help is mandatory
 	 */
@@ -481,11 +489,12 @@ export class Summary<T extends string> {
 	observe(labels: LabelValues<T>, value: number): void;
 
 	/**
-	 * Start a timer where the value in seconds will observed
+	 * Start a timer. Calling the returned function will observe the duration in
+	 * seconds in the summary.
 	 * @param labels Object with label keys and values
 	 * @return Function to invoke when timer should be stopped
 	 */
-	startTimer(labels?: LabelValues<T>): (labels?: LabelValues<T>) => void;
+	startTimer(labels?: LabelValues<T>): (labels?: LabelValues<T>) => number;
 
 	/**
 	 * Reset all values in the summary
@@ -528,11 +537,13 @@ export namespace Summary {
 		observe(value: number): void;
 
 		/**
-		 * Start a timer where the value in seconds will observed
+		 * Start a timer. Calling the returned function will observe the
+		 * duration in seconds in the summary.
 		 * @param labels Object with label keys and values
-		 * @return Function to invoke when timer should be stopped
+		 * @return Function to invoke when timer should be stopped. The value it
+		 * returns is the timed duration.
 		 */
-		startTimer(): (labels?: LabelValues<T>) => void;
+		startTimer(): (labels?: LabelValues<T>) => number;
 	}
 
 	interface Config {
@@ -560,23 +571,23 @@ export class Pushgateway {
 	 */
 	pushAdd(
 		params: Pushgateway.Parameters,
-	): Promise<{ resp?: unknown, body?: unknown }>;
+	): Promise<{ resp?: unknown; body?: unknown }>;
 
 	/**
 	 * Overwrite all metric (using PUT to Pushgateway)
 	 * @param params Push parameters
 	 */
 	push(
 		params: Pushgateway.Parameters,
-	): Promise<{ resp?: unknown, body?: unknown }>;
+	): Promise<{ resp?: unknown; body?: unknown }>;
 
 	/**
 	 * Delete all metrics for jobName
 	 * @param params Push parameters
 	 */
 	delete(
 		params: Pushgateway.Parameters,
-	): Promise<{ resp?: unknown, body?: unknown }>;
+	): Promise<{ resp?: unknown; body?: unknown }>;
 }
 
 export namespace Pushgateway {

lib/defaultMetrics.js

@@ -11,6 +11,7 @@ const processMaxFileDescriptors = require('./metrics/processMaxFileDescriptors')
 const eventLoopLag = require('./metrics/eventLoopLag');
 const processHandles = require('./metrics/processHandles');
 const processRequests = require('./metrics/processRequests');
+const processResources = require('./metrics/processResources');
 const heapSizeAndUsed = require('./metrics/heapSizeAndUsed');
 const heapSpacesSizeAndUsed = require('./metrics/heapSpacesSizeAndUsed');
 const version = require('./metrics/version');
@@ -23,6 +24,9 @@ const metrics = {
 	processOpenFileDescriptors,
 	processMaxFileDescriptors,
 	eventLoopLag,
+	...(typeof process.getActiveResourcesInfo === 'function'
+		? { processResources }
+		: {}),
 	processHandles,
 	processRequests,
 	heapSizeAndUsed,

lib/gauge.js

@@ -8,6 +8,7 @@ const type = 'gauge';
 
 const {
 	setValue,
+	setValueDelta,
 	getLabels,
 	hashObject,
 	isObject,
@@ -50,7 +51,7 @@ class Gauge extends Metric {
 		value = getValueArg(labels, value);
 		labels = getLabelArg(labels);
 		if (value === undefined) value = 1;
-		set(this, labels, this._getValue(labels) + value);
+		setDelta(this, labels, value);
 	}
 
 	/**
@@ -63,7 +64,7 @@ class Gauge extends Metric {
 		value = getValueArg(labels, value);
 		labels = getLabelArg(labels);
 		if (value === undefined) value = 1;
-		set(this, labels, this._getValue(labels) - value);
+		setDelta(this, labels, -value);
 	}
 
 	/**
@@ -94,7 +95,9 @@ class Gauge extends Metric {
 		const start = process.hrtime();
 		return endLabels => {
 			const delta = process.hrtime(start);
-			this.set(Object.assign({}, labels, endLabels), delta[0] + delta[1] / 1e9);
+			const value = delta[0] + delta[1] / 1e9;
+			this.set(Object.assign({}, labels, endLabels), value);
+			return value;
 		};
 	}
 
@@ -145,6 +148,16 @@ function set(gauge, labels, value) {
 	setValue(gauge.hashMap, value, labels);
 }
 
+function setDelta(gauge, labels, delta) {
+	if (typeof delta !== 'number') {
+		throw new TypeError(`Delta is not a valid number: ${util.format(delta)}`);
+	}
+
+	validateLabel(gauge.labelNames, labels);
+	const hash = hashObject(labels);
+	setValueDelta(gauge.hashMap, delta, labels, hash);
+}
+
 function getLabelArg(labels) {
 	return isObject(labels) ? labels : {};
 }

lib/metrics/processResources.js

@@ -0,0 +1,58 @@
+'use strict';
+const Gauge = require('../gauge');
+const { updateMetrics } = require('./helpers/processMetricsHelpers');
+
+const NODEJS_ACTIVE_RESOURCES = 'nodejs_active_resources';
+const NODEJS_ACTIVE_RESOURCES_TOTAL = 'nodejs_active_resources_total';
+
+module.exports = (registry, config = {}) => {
+	// Don't do anything if the function does not exist in previous nodes (exists in node@17.3.0)
+	if (typeof process.getActiveResourcesInfo !== 'function') {
+		return;
+	}
+
+	const namePrefix = config.prefix ? config.prefix : '';
+	const labels = config.labels ? config.labels : {};
+	const labelNames = Object.keys(labels);
+
+	new Gauge({
+		name: namePrefix + NODEJS_ACTIVE_RESOURCES,
+		help:
+			'Number of active resources that are currently keeping the event loop alive, grouped by async resource type.',
+		labelNames: ['type', ...labelNames],
+		registers: registry ? [registry] : undefined,
+		collect() {
+			const resources = process.getActiveResourcesInfo();
+
+			const data = {};
+
+			for (let i = 0; i < resources.length; i++) {
+				const resource = resources[i];
+
+				if (Object.hasOwn(data, resource)) {
+					data[resource] += 1;
+				} else {
+					data[resource] = 1;
+				}
+			}
+
+			updateMetrics(this, data, labels);
+		},
+	});
+
+	new Gauge({
+		name: namePrefix + NODEJS_ACTIVE_RESOURCES_TOTAL,
+		help: 'Total number of active resources.',
+		registers: registry ? [registry] : undefined,
+		labelNames,
+		collect() {
+			const resources = process.getActiveResourcesInfo();
+			this.set(labels, resources.length);
+		},
+	});
+};
+
+module.exports.metricNames = [
+	NODEJS_ACTIVE_RESOURCES,
+	NODEJS_ACTIVE_RESOURCES_TOTAL,
+];

lib/pushgateway.js

@@ -3,6 +3,7 @@
 const url = require('url');
 const http = require('http');
 const https = require('https');
+const { gzipSync } = require('zlib');
 const { globalRegistry } = require('./registry');
 
 class Pushgateway {
@@ -79,6 +80,12 @@ async function useGateway(method, job, groupings) {
 			this.registry
 				.metrics()
 				.then(metrics => {
+					if (
+						options.headers &&
+						options.headers['Content-Encoding'] === 'gzip'
+					) {
+						metrics = gzipSync(metrics);
+					}
 					req.write(metrics);
 					req.end();
 				})