prom-client - npm Package Compare versions

Comparing version 11.5.3 to 12.0.0

CHANGELOG.md

@@ -12,6 +12,28 @@ # Changelog
 
+- Dropped support for end-of-life Node.js versions 6.x and 8.x
+- Dropped the previously deprecated support for positional parameters in
+  constructors, only the config object forms remain.
+- Default metrics are collected on scrape of metrics endpoint, not on an
+  interval. The `timeout` option to `collectDefaultMetrics(conf)` is no longer
+  supported or needed, and the function no longer returns a `Timeout` object.
+
 ### Changed
 
+- chore: remove ignored package-lock.json
+- fix: `process_max_fds` is process limit, not OS (#314)
+- Changed `Metric` labelNames & labelValues in TypeScript declaration to a generic type `T extends string`, instead of `string`
+- Lazy-load Node.js Cluster module to fix Passenger support (#293)
+- fix: avoid mutation bug in `registry.getMetricsAsJSON()`
+- fix: improve performance of `registry.getMetrics*`
+- End function of histogram `startTimer`, when invoked returns the number of seconds
+- chore: reindent package.json
+- chore: correct var name in processStartTime
+- chore: add test for `process_start_time_seconds`
+- chore: spelling corrections in README
+
 ### Added
 
+- feat: implement GC metrics collection without native(C++) modules.
+- faet: implement advanced event loop monitoring
+
 ## [11.5.3] - 2019-06-27
@@ -58,2 +80,3 @@
 ### Added
+
 - Added a `remove()` method on each metric type, based on [Prometheus "Writing Client Libraries" section on labels](https://prometheus.io/docs/instrumenting/writing_clientlibs/#labels)
@@ -60,0 +83,0 @@

index.d.ts

@@ -5,12 +5,2 @@ // Type definitions for prom-client
 /**
- * Options pass to Registry.metrics()
- */
-export interface MetricsOpts {
-	/**
-	 * Whether to include timestamps in the output, defaults to true
-	 */
-	timestamps?: boolean;
-}
-
-/**
  * Container for all registered metrics
@@ -22,3 +12,3 @@ */
 	 */
-	metrics(opts?: MetricsOpts): string;
+	metrics(): string;
 
@@ -39,3 +29,3 @@ /**
 	 */
-	registerMetric(metric: Metric): void;
+	registerMetric<T extends string>(metric: Metric<T>): void;
 
@@ -62,3 +52,3 @@ /**
 	 */
-	getSingleMetric(name: string): Metric;
+	getSingleMetric<T extends string>(name: string): Metric<T>;
 
@@ -131,3 +121,7 @@ /**
  */
-export type Metric = Counter | Gauge | Summary | Histogram;
+export type Metric<T extends string> =
+	| Counter<T>
+	| Gauge<T>
+	| Summary<T>
+	| Histogram<T>;
 
@@ -153,10 +147,8 @@ /**
 
-interface labelValues {
-	[key: string]: string | number;
-}
+type LabelValues<T extends string> = Partial<Record<T, string | number>>;
 
-export interface CounterConfiguration {
+export interface CounterConfiguration<T extends string> {
 	name: string;
 	help: string;
-	labelNames?: string[];
+	labelNames?: T[];
 	registers?: Registry[];
@@ -169,23 +161,14 @@ aggregator?: Aggregator;
  */
-export class Counter {
+export class Counter<T extends string> {
 	/**
 	 * @param configuration Configuration when creating a Counter metric. Name and Help is required.
 	 */
-	constructor(configuration: CounterConfiguration);
+	constructor(configuration: CounterConfiguration<T>);
 
 	/**
-	 * @param name The name of the metric
-	 * @param help Help description
-	 * @param labels Label keys
-	 * @deprecated
-	 */
-	constructor(name: string, help: string, labels?: string[]);
-
-	/**
 	 * Increment for given labels
 	 * @param labels Object with label keys and values
 	 * @param value The number to increment with
-	 * @param timestamp Timestamp to associate the time series with
 	 */
-	inc(labels: labelValues, value?: number, timestamp?: number | Date): void;
+	inc(labels: LabelValues<T>, value?: number): void;
 
@@ -195,5 +178,4 @@ /**
 	 * @param value The value to increment with
-	 * @param timestamp Timestamp to associate the time series with
 	 */
-	inc(value?: number, timestamp?: number | Date): void;
+	inc(value?: number): void;
 
@@ -224,12 +206,11 @@ /**
 		 * @param value The value to increment with
-		 * @param timestamp Timestamp to associate the time series with
 		 */
-		inc(value?: number, timestamp?: number | Date): void;
+		inc(value?: number): void;
 	}
 }
 
-export interface GaugeConfiguration {
+export interface GaugeConfiguration<T extends string> {
 	name: string;
 	help: string;
-	labelNames?: string[];
+	labelNames?: T[];
 	registers?: Registry[];
@@ -242,23 +223,14 @@ aggregator?: Aggregator;
  */
-export class Gauge {
+export class Gauge<T extends string> {
 	/**
 	 * @param configuration Configuration when creating a Gauge metric. Name and Help is mandatory
 	 */
-	constructor(configuration: GaugeConfiguration);
+	constructor(configuration: GaugeConfiguration<T>);
 
 	/**
-	 * @param name The name of the metric
-	 * @param help Help description
-	 * @param labels Label keys
-	 * @deprecated
-	 */
-	constructor(name: string, help: string, labels?: string[]);
-
-	/**
 	 * Increment gauge for given labels
 	 * @param labels Object with label keys and values
 	 * @param value The value to increment with
-	 * @param timestamp Timestamp to associate the time series with
 	 */
-	inc(labels: labelValues, value?: number, timestamp?: number | Date): void;
+	inc(labels: LabelValues<T>, value?: number): void;
 
@@ -268,5 +240,4 @@ /**
 	 * @param value The value to increment with
-	 * @param timestamp Timestamp to associate the time series with
 	 */
-	inc(value?: number, timestamp?: number | Date): void;
+	inc(value?: number): void;
 
@@ -277,5 +248,4 @@ /**
 	 * @param value Value to decrement with
-	 * @param timestamp Timestamp to associate the time series with
 	 */
-	dec(labels: labelValues, value?: number, timestamp?: number | Date): void;
+	dec(labels: LabelValues<T>, value?: number): void;
 
@@ -285,5 +255,4 @@ /**
 	 * @param value The value to decrement with
-	 * @param timestamp Timestamp to associate the time series with
 	 */
-	dec(value?: number, timestamp?: number | Date): void;
+	dec(value?: number): void;
 
@@ -294,5 +263,4 @@ /**
 	 * @param value The value to set
-	 * @param timestamp Timestamp to associate the time series with
 	 */
-	set(labels: labelValues, value: number, timestamp?: number | Date): void;
+	set(labels: LabelValues<T>, value: number): void;
 
@@ -302,5 +270,4 @@ /**
 	 * @param value The value to set
-	 * @param timestamp Timestamp to associate the time series with
 	 */
-	set(value: number, timestamp?: number | Date): void;
+	set(value: number): void;
 
@@ -311,3 +278,3 @@ /**
 	 */
-	setToCurrentTime(labels?: labelValues): void;
+	setToCurrentTime(labels?: LabelValues<T>): void;
 
@@ -319,3 +286,3 @@ /**
 	 */
-	startTimer(labels?: labelValues): (labels?: labelValues) => void;
+	startTimer(labels?: LabelValues<T>): (labels?: LabelValues<T>) => void;
 
@@ -327,3 +294,3 @@ /**
 	 */
-	labels(...values: string[]): Gauge.Internal;
+	labels(...values: string[]): Gauge.Internal<T>;
 
@@ -343,9 +310,8 @@ /**
 export namespace Gauge {
-	interface Internal {
+	interface Internal<T extends string> {
 		/**
 		 * Increment gauge with value
 		 * @param value The value to increment with
-		 * @param timestamp Timestamp to associate the time series with
 		 */
-		inc(value?: number, timestamp?: number | Date): void;
+		inc(value?: number): void;
 
@@ -355,5 +321,4 @@ /**
 		 * @param value The value to decrement with
-		 * @param timestamp Timestamp to associate the time series with
 		 */
-		dec(value?: number, timestamp?: number | Date): void;
+		dec(value?: number): void;
 
@@ -363,5 +328,4 @@ /**
 		 * @param value The value to set
-		 * @param timestamp Timestamp to associate the time series with
 		 */
-		set(value: number, timestamp?: number | Date): void;
+		set(value: number): void;
 
@@ -377,10 +341,10 @@ /**
 		 */
-		startTimer(): (labels?: labelValues) => void;
+		startTimer(): (labels?: LabelValues<T>) => void;
 	}
 }
 
-export interface HistogramConfiguration {
+export interface HistogramConfiguration<T extends string> {
 	name: string;
 	help: string;
-	labelNames?: string[];
+	labelNames?: T[];
 	buckets?: number[];
@@ -394,29 +358,9 @@ registers?: Registry[];
  */
-export class Histogram {
+export class Histogram<T extends string> {
 	/**
 	 * @param configuration Configuration when creating the Histogram. Name and Help is mandatory
 	 */
-	constructor(configuration: HistogramConfiguration);
+	constructor(configuration: HistogramConfiguration<T>);
 
 	/**
-	 * @param name The name of metric
-	 * @param help Help description
-	 * @param labels Label keys
-	 * @param config Configuration object for Histograms
-	 */
-	constructor(
-		name: string,
-		help: string,
-		labels?: string[],
-		config?: Histogram.Config
-	);
-	/**
-	 * @param name The name of metric
-	 * @param help Help description
-	 * @param config Configuration object for Histograms
-	 * @deprecated
-	 */
-	constructor(name: string, help: string, config: Histogram.Config);
-
-	/**
 	 * Observe value
@@ -431,3 +375,3 @@ * @param value The value to observe
 	 */
-	observe(labels: labelValues, value: number): void;
+	observe(labels: LabelValues<T>, value: number): void;
 
@@ -439,3 +383,3 @@ /**
 	 */
-	startTimer(labels?: labelValues): (labels?: labelValues) => void;
+	startTimer(labels?: LabelValues<T>): (labels?: LabelValues<T>) => void;
 
@@ -452,3 +396,3 @@ /**
 	 */
-	labels(...values: string[]): Histogram.Internal;
+	labels(...values: string[]): Histogram.Internal<T>;
 
@@ -463,3 +407,3 @@ /**
 export namespace Histogram {
-	interface Internal {
+	interface Internal<T extends string> {
 		/**
@@ -476,3 +420,3 @@ * Observe value
 		 */
-		startTimer(): (labels?: labelValues) => void;
+		startTimer(): (labels?: LabelValues<T>) => void;
 	}
@@ -488,6 +432,6 @@
 
-export interface SummaryConfiguration {
+export interface SummaryConfiguration<T extends string> {
 	name: string;
 	help: string;
-	labelNames?: string[];
+	labelNames?: T[];
 	percentiles?: number[];
@@ -504,29 +448,9 @@ registers?: Registry[];
  */
-export class Summary {
+export class Summary<T extends string> {
 	/**
 	 * @param configuration Configuration when creating Summary metric. Name and Help is mandatory
 	 */
-	constructor(configuration: SummaryConfiguration);
+	constructor(configuration: SummaryConfiguration<T>);
 
 	/**
-	 * @param name The name of the metric
-	 * @param help Help description
-	 * @param labels Label keys
-	 * @param config Configuration object
-	 */
-	constructor(
-		name: string,
-		help: string,
-		labels?: string[],
-		config?: Summary.Config
-	);
-	/**
-	 * @param name The name of the metric
-	 * @param help Help description
-	 * @param config Configuration object
-	 * @deprecated
-	 */
-	constructor(name: string, help: string, config: Summary.Config);
-
-	/**
 	 * Observe value in summary
@@ -541,3 +465,3 @@ * @param value The value to observe
 	 */
-	observe(labels: labelValues, value: number): void;
+	observe(labels: LabelValues<T>, value: number): void;
 
@@ -549,3 +473,3 @@ /**
 	 */
-	startTimer(labels?: labelValues): (labels?: labelValues) => void;
+	startTimer(labels?: LabelValues<T>): (labels?: LabelValues<T>) => void;
 
@@ -562,3 +486,3 @@ /**
 	 */
-	labels(...values: string[]): Summary.Internal;
+	labels(...values: string[]): Summary.Internal<T>;
 
@@ -573,3 +497,3 @@ /**
 export namespace Summary {
-	interface Internal {
+	interface Internal<T extends string> {
 		/**
@@ -586,3 +510,3 @@ * Observe value in summary
 		 */
-		startTimer(): (labels?: labelValues) => void;
+		startTimer(): (labels?: LabelValues<T>) => void;
 	}
@@ -682,6 +606,6 @@
 export interface DefaultMetricsCollectorConfiguration {
-	timeout?: number;
-	timestamps?: boolean;
 	register?: Registry;
 	prefix?: string;
+	gcDurationBuckets?: number[];
+	eventLoopMonitoringPrecision?: number;
 }
@@ -692,16 +616,7 @@
  * @param config Configuration object for default metrics collector
- * @return The setInterval number
  */
 export function collectDefaultMetrics(
 	config?: DefaultMetricsCollectorConfiguration
-): ReturnType<typeof setInterval>;
+): void;
 
-/**
- * Configure default metrics
- * @param timeout The interval how often the default metrics should be probed
- * @deprecated A number to defaultMetrics is deprecated, please use \`collectDefaultMetrics({ timeout: ${timeout} })\`.
- * @return The setInterval number
- */
-export function collectDefaultMetrics(timeout: number): number;
-
 export interface defaultMetrics {
@@ -708,0 +623,0 @@ /**

lib/cluster.js

@@ -11,6 +11,12 @@ 'use strict';
 
-const cluster = require('cluster');
 const Registry = require('./registry');
 const { Grouper } = require('./util');
 const { aggregators } = require('./metricAggregators');
+// We need to lazy-load the 'cluster' module as some application servers -
+// namely Passenger - crash when it is imported.
+let cluster = () => {
+	const data = require('cluster');
+	cluster = () => data;
+	return data;
+};
 
@@ -70,7 +76,7 @@ const GET_METRICS_REQ = 'prom-client:getMetricsReq';
 
-			for (const id in cluster.workers) {
+			for (const id in cluster().workers) {
 				// If the worker exits abruptly, it may still be in the workers
 				// list but not able to communicate.
-				if (cluster.workers[id].isConnected()) {
-					cluster.workers[id].send(message);
+				if (cluster().workers[id].isConnected()) {
+					cluster().workers[id].send(message);
 					request.pending++;
@@ -158,5 +164,5 @@ }
 
-	if (cluster.isMaster) {
+	if (cluster().isMaster) {
 		// Listen for worker responses to requests for local metrics
-		cluster.on('message', (worker, message) => {
+		cluster().on('message', (worker, message) => {
 			if (message.type === GET_METRICS_RES) {
@@ -183,15 +189,13 @@ const request = requests.get(message.requestId);
 
-if (cluster.isWorker) {
-	// Respond to master's requests for worker's local metrics.
-	process.on('message', message => {
-		if (message.type === GET_METRICS_REQ) {
-			process.send({
-				type: GET_METRICS_RES,
-				requestId: message.requestId,
-				metrics: registries.map(r => r.getMetricsAsJSON())
-			});
-		}
-	});
-}
+// Respond to master's requests for worker's local metrics.
+process.on('message', message => {
+	if (cluster().isWorker && message.type === GET_METRICS_REQ) {
+		process.send({
+			type: GET_METRICS_RES,
+			requestId: message.requestId,
+			metrics: registries.map(r => r.getMetricsAsJSON())
+		});
+	}
+});
 
 module.exports = AggregatorRegistry;

lib/counter.js

@@ -10,7 +10,5 @@ /**
 const {
-	isDate,
 	getPropertiesFromObj,
 	hashObject,
 	isObject,
-	printDeprecationObjectConstructor,
 	getLabels,
@@ -29,30 +27,20 @@ removeLabels
 	 * Counter
-	 * @param {string} name - Name of the metric
-	 * @param {string} help - Help description for the metric
-	 * @param {Array.<string>} labels - Labels
+	 * @param {config} config - Configuration object.
+	 * @param {string} config.name - Name of the metric
+	 * @param {string} config.help - Help description for the metric
+	 * @param {Array.<string>} config.labels - Array with strings, all label keywords supported
 	 */
-	constructor(name, help, labels) {
-		let config;
-		if (isObject(name)) {
-			config = Object.assign(
-				{
-					labelNames: []
-				},
-				name
-			);
-
-			if (!config.registers) {
-				config.registers = [globalRegistry];
-			}
-		} else {
-			printDeprecationObjectConstructor();
-
-			config = {
-				name,
-				help,
-				labelNames: labels,
-				registers: [globalRegistry]
-			};
+	constructor(config) {
+		if (!isObject(config)) {
+			throw new TypeError('constructor expected a config object');
 		}
-
+		config = Object.assign(
+			{
+				labelNames: []
+			},
+			config
+		);
+		if (!config.registers) {
+			config.registers = [globalRegistry];
+		}
 		if (!config.help) {
@@ -67,3 +55,2 @@ throw new Error('Missing mandatory help parameter');
 		}
-
 		if (!validateLabelName(config.labelNames)) {
@@ -74,7 +61,4 @@ throw new Error('Invalid label name');
 		this.name = config.name;
-
 		this.labelNames = config.labelNames || [];
-
 		this.reset();
-
 		this.help = config.help;
@@ -92,6 +76,5 @@ this.aggregator = config.aggregator || 'sum';
 	 * @param {Number} value - Value to increment, if omitted increment with 1
-	 * @param {(Number|Date)} timestamp - Timestamp to set the counter to
 	 * @returns {void}
 	 */
-	inc(labels, value, timestamp) {
+	inc(labels, value) {
 		if (!isObject(labels)) {
@@ -102,3 +85,3 @@ return inc.call(this, null)(labels, value);
 		const hash = hashObject(labels);
-		return inc.call(this, labels, hash)(value, timestamp);
+		return inc.call(this, labels, hash)(value);
 	}
@@ -148,11 +131,6 @@
 const inc = function(labels, hash) {
-	return (value, timestamp) => {
+	return value => {
 		if (value && !Number.isFinite(value)) {
 			throw new TypeError(`Value is not a valid number: ${util.format(value)}`);
 		}
-		if (timestamp && !isDate(timestamp) && !Number.isFinite(timestamp)) {
-			throw new TypeError(
-				`Timestamp is not a valid date or number: ${util.format(timestamp)}`
-			);
-		}
 		if (value < 0) {
@@ -167,18 +145,12 @@ throw new Error('It is not possible to decrease a counter');
 
-		this.hashMap = setValue(this.hashMap, incValue, timestamp, labels, hash);
+		this.hashMap = setValue(this.hashMap, incValue, labels, hash);
 	};
 };
 
-function setValue(hashMap, value, timestamp, labels, hash) {
+function setValue(hashMap, value, labels, hash) {
 	hash = hash || '';
-	timestamp = isDate(timestamp)
-		? timestamp.valueOf()
-		: Number.isFinite(timestamp)
-		? timestamp
-		: undefined;
 	if (hashMap[hash]) {
 		hashMap[hash].value += value;
-		hashMap[hash].timestamp = timestamp;
 	} else {
-		hashMap[hash] = { value, labels: labels || {}, timestamp };
+		hashMap[hash] = { value, labels: labels || {} };
 	}
@@ -185,0 +157,0 @@ return hashMap;

lib/defaultMetrics.js

 'use strict';
 
+const { isObject } = require('./util');
+const { globalRegistry } = require('./registry');
+
+// Default metrics.
 const processCpuTotal = require('./metrics/processCpuTotal');
@@ -14,4 +18,3 @@ const processStartTime = require('./metrics/processStartTime');
 const version = require('./metrics/version');
-const { globalRegistry } = require('./registry');
-const { printDeprecationCollectDefaultMetricsNumber } = require('./util');
+const gc = require('./metrics/gc');
 
@@ -29,59 +32,49 @@ const metrics = {
 	heapSpacesSizeAndUsed,
-	version
+	version,
+	gc
 };
 const metricsList = Object.keys(metrics);
 
-let existingInterval = null;
-// This is used to ensure the program throws on duplicate metrics during first run
-// We might want to consider not supporting running the default metrics function more than once
-let init = true;
+module.exports = function collectDefaultMetrics(config) {
+	if (config !== null && config !== undefined && !isObject(config)) {
+		throw new TypeError('config must be null, undefined, or an object');
+	}
 
-module.exports = function startDefaultMetrics(config) {
-	let normalizedConfig = config;
-	if (typeof config === 'number') {
-		printDeprecationCollectDefaultMetricsNumber(config);
+	config = Object.assign({ eventLoopMonitoringPrecision: 10 }, config);
 
-		normalizedConfig = { timeout: config };
-	}
+	const registry = config.register || globalRegistry;
+	const last = registry
+		.collectors()
+		.find(collector => collector._source === metrics);
 
-	normalizedConfig = Object.assign(
-		{
-			timestamps: true,
-			timeout: 10000
-		},
-		normalizedConfig
-	);
-
-	if (existingInterval !== null) {
-		clearInterval(existingInterval);
+	if (last) {
+		throw new Error(
+			'Cannot add the default metrics twice to the same registry'
+		);
 	}
 
-	const initialisedMetrics = metricsList.map(metric => {
-		const defaultMetric = metrics[metric];
-		if (!init) {
-			defaultMetric.metricNames.map(
-				globalRegistry.removeSingleMetric,
-				globalRegistry
-			);
-		}
-
-		return defaultMetric(normalizedConfig.register, normalizedConfig);
+	const scrapers = metricsList.map(key => {
+		const metric = metrics[key];
+		return metric(config.register, config);
 	});
 
-	function updateAllMetrics() {
-		initialisedMetrics.forEach(metric => metric.call());
+	// Ideally the library would be based around a concept of collectors and
+	// async callbacks, but in the short-term, trigger scraping of the
+	// current metric value synchronously.
+	// - // https://prometheus.io/docs/instrumenting/writing_clientlibs/#overall-structure
+	function defaultMetricCollector() {
+		scrapers.forEach(scraper => scraper());
 	}
 
-	updateAllMetrics();
+	// defaultMetricCollector has to be dynamic, because the scrapers are in
+	// its closure, but we still want to identify a default collector, so
+	// tag it with a value known only to this module (the const metric array
+	// value) so we can find it later.
+	defaultMetricCollector._source = metrics;
+	registry.registerCollector(defaultMetricCollector);
 
-	existingInterval = setInterval(
-		updateAllMetrics,
-		normalizedConfig.timeout
-	).unref();
-
-	init = false;
-
-	return existingInterval;
+	// Because the tests expect an immediate collection.
+	defaultMetricCollector();
 };
 
 module.exports.metricsList = metricsList;

lib/gauge.js

@@ -11,3 +11,2 @@ /**
 const {
-	isDate,
 	setValue,
@@ -18,3 +17,2 @@ getPropertiesFromObj,
 	isObject,
-	printDeprecationObjectConstructor,
 	removeLabels
@@ -31,29 +29,20 @@ } = require('./util');
 	 * Gauge
-	 * @param {string} name - Name of the metric
-	 * @param {string} help - Help for the metric
-	 * @param {Array.<string>} labels - Array with strings, all label keywords supported
+	 * @param {config} config - Configuration object
+	 * @param {string} config.name - Name of the metric
+	 * @param {string} config.help - Help description for the metric
+	 * @param {Array.<string>} config.labels - Array with strings, all label keywords supported
 	 */
-	constructor(name, help, labels) {
-		let config;
-		if (isObject(name)) {
-			config = Object.assign(
-				{
-					labelNames: []
-				},
-				name
-			);
-
-			if (!config.registers) {
-				config.registers = [globalRegistry];
-			}
-		} else {
-			printDeprecationObjectConstructor();
-			config = {
-				name,
-				help,
-				labelNames: labels,
-				registers: [globalRegistry]
-			};
+	constructor(config) {
+		if (!isObject(config)) {
+			throw new TypeError('constructor expected a config object');
 		}
-
+		config = Object.assign(
+			{
+				labelNames: []
+			},
+			config
+		);
+		if (!config.registers) {
+			config.registers = [globalRegistry];
+		}
 		if (!config.help) {
@@ -87,10 +76,9 @@ throw new Error('Missing mandatory help parameter');
 	 * @param {Number} value - Value to set the gauge to, must be positive
-	 * @param {(Number|Date)} timestamp - Timestamp to set the gauge to
 	 * @returns {void}
 	 */
-	set(labels, value, timestamp) {
+	set(labels, value) {
 		if (!isObject(labels)) {
 			return set.call(this, null)(labels, value);
 		}
-		return set.call(this, labels)(value, timestamp);
+		return set.call(this, labels)(value);
 	}
@@ -110,7 +98,6 @@
 	 * @param {Number} value - Value to increment - if omitted, increment with 1
-	 * @param {(Number|Date)} timestamp - Timestamp to set the gauge to
 	 * @returns {void}
 	 */
-	inc(labels, value, timestamp) {
-		inc.call(this, labels)(value, timestamp);
+	inc(labels, value) {
+		inc.call(this, labels)(value);
 	}
@@ -122,7 +109,6 @@
 	 * @param {Number} value - Value to decrement - if omitted, decrement with 1
-	 * @param {(Number|Date)} timestamp - Timestamp to set the gauge to
 	 * @returns {void}
 	 */
-	dec(labels, value, timestamp) {
-		dec.call(this, labels)(value, timestamp);
+	dec(labels, value) {
+		dec.call(this, labels)(value);
 	}
@@ -210,9 +196,5 @@
 function dec(labels) {
-	return (value, timestamp) => {
+	return value => {
 		const data = convertLabelsAndValues(labels, value);
-		this.set(
-			data.labels,
-			this._getValue(data.labels) - (data.value || 1),
-			timestamp
-		);
+		this.set(data.labels, this._getValue(data.labels) - (data.value || 1));
 	};
@@ -222,9 +204,5 @@ }
 function inc(labels) {
-	return (value, timestamp) => {
+	return value => {
 		const data = convertLabelsAndValues(labels, value);
-		this.set(
-			data.labels,
-			this._getValue(data.labels) + (data.value || 1),
-			timestamp
-		);
+		this.set(data.labels, this._getValue(data.labels) + (data.value || 1));
 	};
@@ -234,11 +212,6 @@ }
 function set(labels) {
-	return (value, timestamp) => {
+	return value => {
 		if (typeof value !== 'number') {
 			throw new TypeError(`Value is not a valid number: ${util.format(value)}`);
 		}
-		if (timestamp && !isDate(timestamp) && !Number.isFinite(timestamp)) {
-			throw new TypeError(
-				`Timestamp is not a valid date or number: ${util.format(timestamp)}`
-			);
-		}
 
@@ -248,3 +221,3 @@ labels = labels || {};
 		validateLabel(this.labelNames, labels);
-		this.hashMap = setValue(this.hashMap, value, labels, timestamp);
+		this.hashMap = setValue(this.hashMap, value, labels);
 	};
@@ -251,0 +224,0 @@ }

lib/histogram.js

@@ -14,3 +14,2 @@ /**
 	isObject,
-	printDeprecationObjectConstructor,
 	removeLabels
@@ -27,43 +26,21 @@ } = require('./util');
 	 * Histogram
-	 * @param {string} name - Name of the metric
-	 * @param {string} help - Help for the metric
-	 * @param {object|Array.<string>} labelsOrConf - Either array of label names or config object as a key-value object
-	 * @param {object} conf - Configuration object
+	 * @param {config} config - Configuration object.
+	 * @param {string} config.name - Name of the metric
+	 * @param {string} config.help - Help for the metric
+	 * @param {Array.<string>} config.labels - Array with strings, all label keywords supported
 	 */
-	constructor(name, help, labelsOrConf, conf) {
-		let config;
-
-		if (isObject(name)) {
-			config = Object.assign(
-				{
-					buckets: [0.005, 0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1, 2.5, 5, 10],
-					labelNames: []
-				},
-				name
-			);
-
-			if (!config.registers) {
-				config.registers = [globalRegistry];
-			}
-		} else {
-			let obj;
-			let labels = [];
-
-			if (Array.isArray(labelsOrConf)) {
-				obj = conf || {};
-				labels = labelsOrConf;
-			} else {
-				obj = labelsOrConf || {};
-			}
-
-			printDeprecationObjectConstructor();
-
-			config = {
-				name,
-				labelNames: labels,
-				help,
-				buckets: configureUpperbounds(obj.buckets),
-				registers: [globalRegistry]
-			};
+	constructor(config) {
+		if (!isObject(config)) {
+			throw new TypeError('constructor expected a config object');
 		}
+		config = Object.assign(
+			{
+				buckets: [0.005, 0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1, 2.5, 5, 10],
+				labelNames: []
+			},
+			config
+		);
+		if (!config.registers) {
+			config.registers = [globalRegistry];
+		}
 		validateInput(config.name, config.help, config.labelNames);
@@ -141,3 +118,4 @@
 	 * makeExpensiveXHRRequest(function(err, res) {
-	 *	end(); //Observe the duration of expensiveXHRRequest
+	 * 	const duration = end(); //Observe the duration of expensiveXHRRequest and returns duration in seconds
+	 * 	console.log('Duration', duration);
 	 * });
@@ -168,9 +146,9 @@ */
 			const delta = process.hrtime(start);
-			this.observe(
-				Object.assign({}, startLabels, endLabels),
-				delta[0] + delta[1] / 1e9
-			);
+			const value = delta[0] + delta[1] / 1e9;
+			this.observe(Object.assign({}, startLabels, endLabels), value);
+			return value;
 		};
 	};
 }
+
 function validateInput(name, help, labels) {
@@ -199,23 +177,2 @@ if (!help) {
 
-function configureUpperbounds(configuredBuckets) {
-	const defaultBuckets = [
-		0.005,
-		0.01,
-		0.025,
-		0.05,
-		0.1,
-		0.25,
-		0.5,
-		1,
-		2.5,
-		5,
-		10
-	];
-	return [].concat(configuredBuckets || defaultBuckets).sort(sortAscending);
-}
-
-function sortAscending(x, y) {
-	return x - y;
-}
-
 function setValuePair(labels, value, metricName) {
@@ -264,3 +221,3 @@ return {
 
-		if (valueFromMap.bucketValues.hasOwnProperty(b)) {
+		if (Object.prototype.hasOwnProperty.call(valueFromMap.bucketValues, b)) {
 			valueFromMap.bucketValues[b] += 1;
@@ -267,0 +224,0 @@ }

lib/metrics/eventLoopLag.js

@@ -5,4 +5,24 @@ 'use strict';
 
+// Check if perf_hooks module is available
+let perf_hooks;
+try {
+	/* eslint-disable node/no-unsupported-features/node-builtins */
+	perf_hooks = require('perf_hooks');
+} catch (e) {
+	// node version is too old
+}
+
+// Reported always, but because legacy lag_seconds is collected async, the value
+// will always be stale by one scrape interval.
 const NODEJS_EVENTLOOP_LAG = 'nodejs_eventloop_lag_seconds';
 
+// Reported only when perf_hooks is available.
+const NODEJS_EVENTLOOP_LAG_MIN = 'nodejs_eventloop_lag_min_seconds';
+const NODEJS_EVENTLOOP_LAG_MAX = 'nodejs_eventloop_lag_max_seconds';
+const NODEJS_EVENTLOOP_LAG_MEAN = 'nodejs_eventloop_lag_mean_seconds';
+const NODEJS_EVENTLOOP_LAG_STDDEV = 'nodejs_eventloop_lag_stddev_seconds';
+const NODEJS_EVENTLOOP_LAG_P50 = 'nodejs_eventloop_lag_p50_seconds';
+const NODEJS_EVENTLOOP_LAG_P90 = 'nodejs_eventloop_lag_p90_seconds';
+const NODEJS_EVENTLOOP_LAG_P99 = 'nodejs_eventloop_lag_p99_seconds';
+
 function reportEventloopLag(start, gauge) {
@@ -13,3 +33,3 @@ const delta = process.hrtime(start);
 
-	gauge.set(seconds, Date.now());
+	gauge.set(seconds);
 }
@@ -20,3 +40,3 @@
 
-	const gauge = new Gauge({
+	const lag = new Gauge({
 		name: namePrefix + NODEJS_EVENTLOOP_LAG,
@@ -27,9 +47,73 @@ help: 'Lag of event loop in seconds.',
 	});
+	const lagMin = new Gauge({
+		name: namePrefix + NODEJS_EVENTLOOP_LAG_MIN,
+		help: 'The minimum recorded event loop delay.',
+		registers: registry ? [registry] : undefined
+	});
+	const lagMax = new Gauge({
+		name: namePrefix + NODEJS_EVENTLOOP_LAG_MAX,
+		help: 'The maximum recorded event loop delay.',
+		registers: registry ? [registry] : undefined
+	});
+	const lagMean = new Gauge({
+		name: namePrefix + NODEJS_EVENTLOOP_LAG_MEAN,
+		help: 'The mean of the recorded event loop delays.',
+		registers: registry ? [registry] : undefined
+	});
+	const lagStddev = new Gauge({
+		name: namePrefix + NODEJS_EVENTLOOP_LAG_STDDEV,
+		help: 'The standard deviation of the recorded event loop delays.',
+		registers: registry ? [registry] : undefined
+	});
+	const lagP50 = new Gauge({
+		name: namePrefix + NODEJS_EVENTLOOP_LAG_P50,
+		help: 'The 50th percentile of the recorded event loop delays.',
+		registers: registry ? [registry] : undefined
+	});
+	const lagP90 = new Gauge({
+		name: namePrefix + NODEJS_EVENTLOOP_LAG_P90,
+		help: 'The 90th percentile of the recorded event loop delays.',
+		registers: registry ? [registry] : undefined
+	});
+	const lagP99 = new Gauge({
+		name: namePrefix + NODEJS_EVENTLOOP_LAG_P99,
+		help: 'The 99th percentile of the recorded event loop delays.',
+		registers: registry ? [registry] : undefined
+	});
 
+	if (!perf_hooks || !perf_hooks.monitorEventLoopDelay) {
+		return () => {
+			const start = process.hrtime();
+			setImmediate(reportEventloopLag, start, lag);
+		};
+	}
+
+	const histogram = perf_hooks.monitorEventLoopDelay({
+		resolution: config.eventLoopMonitoringPrecision
+	});
+	histogram.enable();
+
 	return () => {
 		const start = process.hrtime();
-		setImmediate(reportEventloopLag, start, gauge);
+		setImmediate(reportEventloopLag, start, lag);
+
+		lagMin.set(histogram.min / 1e9);
+		lagMax.set(histogram.max / 1e9);
+		lagMean.set(histogram.mean / 1e9);
+		lagStddev.set(histogram.stddev / 1e9);
+		lagP50.set(histogram.percentile(50) / 1e9);
+		lagP90.set(histogram.percentile(90) / 1e9);
+		lagP99.set(histogram.percentile(99) / 1e9);
 	};
 };
 
-module.exports.metricNames = [NODEJS_EVENTLOOP_LAG];
+module.exports.metricNames = [
+	NODEJS_EVENTLOOP_LAG,
+	NODEJS_EVENTLOOP_LAG_MIN,
+	NODEJS_EVENTLOOP_LAG_MAX,
+	NODEJS_EVENTLOOP_LAG_MEAN,
+	NODEJS_EVENTLOOP_LAG_STDDEV,
+	NODEJS_EVENTLOOP_LAG_P50,
+	NODEJS_EVENTLOOP_LAG_P90,
+	NODEJS_EVENTLOOP_LAG_P99
+];

lib/metrics/heapSizeAndUsed.js

@@ -20,3 +20,3 @@ 'use strict';
 		name: namePrefix + NODEJS_HEAP_SIZE_TOTAL,
-		help: 'Process heap size from node.js in bytes.',
+		help: 'Process heap size from Node.js in bytes.',
 		registers
@@ -26,33 +26,19 @@ });
 		name: namePrefix + NODEJS_HEAP_SIZE_USED,
-		help: 'Process heap size used from node.js in bytes.',
+		help: 'Process heap size used from Node.js in bytes.',
 		registers
 	});
-	let externalMemUsed;
+	const externalMemUsed = new Gauge({
+		name: namePrefix + NODEJS_EXTERNAL_MEMORY,
+		help: 'Node.js external memory size in bytes.',
+		registers
+	});
 
-	const usage = safeMemoryUsage();
-	if (usage && usage.external) {
-		externalMemUsed = new Gauge({
-			name: namePrefix + NODEJS_EXTERNAL_MEMORY,
-			help: 'Nodejs external memory size in bytes.',
-			registers
-		});
-	}
-
 	return () => {
-		// process.memoryUsage() can throw EMFILE errors, see #67
+		// process.memoryUsage() can throw on some platforms, see #67
 		const memUsage = safeMemoryUsage();
 		if (memUsage) {
-			if (config.timestamps) {
-				const now = Date.now();
-				heapSizeTotal.set(memUsage.heapTotal, now);
-				heapSizeUsed.set(memUsage.heapUsed, now);
-				if (memUsage.external && externalMemUsed) {
-					externalMemUsed.set(memUsage.external, now);
-				}
-			} else {
-				heapSizeTotal.set(memUsage.heapTotal);
-				heapSizeUsed.set(memUsage.heapUsed);
-				if (memUsage.external && externalMemUsed) {
-					externalMemUsed.set(memUsage.external);
-				}
+			heapSizeTotal.set(memUsage.heapTotal);
+			heapSizeUsed.set(memUsage.heapUsed);
+			if (memUsage.external && externalMemUsed) {
+				externalMemUsed.set(memUsage.external);
 			}
@@ -59,0 +45,0 @@ }

lib/metrics/heapSpacesSizeAndUsed.js

 'use strict';
 
 const Gauge = require('../gauge');
-let v8;
+const v8 = require('v8');
 
-try {
-	v8 = require('v8');
-} catch (e) {
-	// node version is too old
-	// probably we can use v8-heap-space-statistics for >=node-4.0.0 and <node-6.0.0
-}
-
 const METRICS = ['total', 'used', 'available'];
-
 const NODEJS_HEAP_SIZE = {};
@@ -22,9 +14,2 @@
 module.exports = (registry, config = {}) => {
-	if (
-		typeof v8 === 'undefined' ||
-		typeof v8.getHeapSpaceStatistics !== 'function'
-	) {
-		return () => {};
-	}
-
 	const registers = registry ? [registry] : undefined;
@@ -38,3 +23,3 @@ const namePrefix = config.prefix ? config.prefix : '';
 			name: namePrefix + NODEJS_HEAP_SIZE[metricType],
-			help: `Process heap space size ${metricType} from node.js in bytes.`,
+			help: `Process heap space size ${metricType} from Node.js in bytes.`,
 			labelNames: ['space'],
@@ -41,0 +26,0 @@ registers

lib/metrics/helpers/processMetricsHelpers.js

@@ -13,3 +13,3 @@ 'use strict';
 
-		if (data.hasOwnProperty(listElement.constructor.name)) {
+		if (Object.hasOwnProperty.call(data, listElement.constructor.name)) {
 			data[listElement.constructor.name] += 1;
@@ -23,10 +23,6 @@ } else {
 
-function updateMetrics(gauge, data, includeTimestamp) {
+function updateMetrics(gauge, data) {
 	gauge.reset();
 	for (const key in data) {
-		if (includeTimestamp) {
-			gauge.set({ type: key }, data[key], Date.now());
-		} else {
-			gauge.set({ type: key }, data[key]);
-		}
+		gauge.set({ type: key }, data[key]);
 	}
@@ -33,0 +29,0 @@ }

lib/metrics/helpers/safeMemoryUsage.js

 'use strict';
 
 function safeMemoryUsage() {
-	let memoryUsage;
 	try {
-		memoryUsage = process.memoryUsage();
+		return process.memoryUsage();
 	} catch (ex) {
-		// empty
+		return;
 	}
-
-	return memoryUsage;
 }
 
 module.exports = safeMemoryUsage;

lib/metrics/osMemoryHeapLinux.js

@@ -54,14 +54,19 @@ 'use strict';
 
+	// Sync I/O is often problematic, but /proc isn't really I/O, it a
+	// virtual filesystem that maps directly to in-kernel data structures
+	// and never blocks.
+	//
+	// Node.js/libuv do this already for process.memoryUsage(), see:
+	// - https://github.com/libuv/libuv/blob/a629688008694ed8022269e66826d4d6ec688b83/src/unix/linux-core.c#L506-L523
 	return () => {
-		fs.readFile('/proc/self/status', 'utf8', (err, status) => {
-			if (err) {
-				return;
-			}
-			const now = Date.now();
-			const structuredOutput = structureOutput(status);
+		try {
+			const stat = fs.readFileSync('/proc/self/status', 'utf8');
+			const structuredOutput = structureOutput(stat);
 
-			residentMemGauge.set(structuredOutput.VmRSS, now);
-			virtualMemGauge.set(structuredOutput.VmSize, now);
-			heapSizeMemGauge.set(structuredOutput.VmData, now);
-		});
+			residentMemGauge.set(structuredOutput.VmRSS);
+			virtualMemGauge.set(structuredOutput.VmSize);
+			heapSizeMemGauge.set(structuredOutput.VmData);
+		} catch (er) {
+			return;
+		}
 	};
@@ -68,0 +73,0 @@ };

lib/metrics/processCpuTotal.js

@@ -9,7 +9,2 @@ 'use strict';
 module.exports = (registry, config = {}) => {
-	// Don't do anything if the function doesn't exist (introduced in node@6.1.0)
-	if (typeof process.cpuUsage !== 'function') {
-		return () => {};
-	}
-
 	const registers = registry ? [registry] : undefined;
@@ -16,0 +11,0 @@ const namePrefix = config.prefix ? config.prefix : '';

lib/metrics/processHandles.js

@@ -31,15 +31,7 @@ 'use strict';
 
-	const updater = config.timestamps
-		? () => {
-				const handles = process._getActiveHandles();
-				updateMetrics(gauge, aggregateByObjectName(handles), true);
-				totalGauge.set(handles.length, Date.now());
-		  }
-		: () => {
-				const handles = process._getActiveHandles();
-				updateMetrics(gauge, aggregateByObjectName(handles), false);
-				totalGauge.set(handles.length);
-		  };
-
-	return updater;
+	return () => {
+		const handles = process._getActiveHandles();
+		updateMetrics(gauge, aggregateByObjectName(handles));
+		totalGauge.set(handles.length);
+	};
 };
@@ -46,0 +38,0 @@

lib/metrics/processMaxFileDescriptors.js

@@ -8,11 +8,25 @@ 'use strict';
 
+let maxFds;
+
 module.exports = (registry, config = {}) => {
-	let isSet = false;
-
-	if (process.platform !== 'linux') {
-		return () => {};
+	if (maxFds === undefined) {
+		// This will fail if a linux-like procfs is not available.
+		try {
+			const limits = fs.readFileSync('/proc/self/limits', 'utf8');
+			const lines = limits.split('\n');
+			lines.find(line => {
+				if (line.startsWith('Max open files')) {
+					const parts = line.split(/  +/);
+					maxFds = Number(parts[1]);
+					return true;
+				}
+			});
+		} catch (er) {
+			return () => {};
+		}
 	}
 
+	if (maxFds === undefined) return () => {};
+
 	const namePrefix = config.prefix ? config.prefix : '';
-
 	const fileDescriptorsGauge = new Gauge({
@@ -24,19 +38,7 @@ name: namePrefix + PROCESS_MAX_FDS,
 
-	return () => {
-		if (isSet) {
-			return;
-		}
+	fileDescriptorsGauge.set(Number(maxFds));
 
-		fs.readFile('/proc/sys/fs/file-max', 'utf8', (err, maxFds) => {
-			if (err) {
-				return;
-			}
-
-			isSet = true;
-
-			fileDescriptorsGauge.set(Number(maxFds));
-		});
-	};
+	return () => {};
 };
 
 module.exports.metricNames = [PROCESS_MAX_FDS];

lib/metrics/processOpenFileDescriptors.js

@@ -23,10 +23,10 @@ 'use strict';
 	return () => {
-		fs.readdir('/proc/self/fd', (err, list) => {
-			if (err) {
-				return;
-			}
-
-			// Minus 1, as this invocation created one
-			fileDescriptorsGauge.set(list.length - 1, Date.now());
-		});
+		try {
+			const fds = fs.readdirSync('/proc/self/fd');
+			// Minus 1 to not count the fd that was used by readdirSync(), its now
+			// closed.
+			fileDescriptorsGauge.set(fds.length - 1);
+		} catch (er) {
+			return;
+		}
 	};
@@ -33,0 +33,0 @@ };

lib/metrics/processStartTime.js

 'use strict';
 
 const Gauge = require('../gauge');
-const nowInSeconds = Math.round(Date.now() / 1000 - process.uptime());
+const startInSeconds = Math.round(Date.now() / 1000 - process.uptime());
 
@@ -17,13 +17,7 @@ const PROCESS_START_TIME = 'process_start_time_seconds';
 	});
-	let isSet = false;
+	cpuUserGauge.set(startInSeconds);
 
-	return () => {
-		if (isSet) {
-			return;
-		}
-		cpuUserGauge.set(nowInSeconds);
-		isSet = true;
-	};
+	return () => {};
 };
 
 module.exports.metricNames = [PROCESS_START_TIME];

lib/metrics/version.js

@@ -22,20 +22,9 @@ 'use strict';
 	});
-	let isSet = false;
+	nodeVersionGauge
+		.labels(version, versionSegments[0], versionSegments[1], versionSegments[2])
+		.set(1);
 
-	return () => {
-		if (isSet) {
-			return;
-		}
-		nodeVersionGauge
-			.labels(
-				version,
-				versionSegments[0],
-				versionSegments[1],
-				versionSegments[2]
-			)
-			.set(1);
-		isSet = true;
-	};
+	return () => {};
 };
 
 module.exports.metricNames = [NODE_VERSION_INFO];

lib/pushgateway.js

@@ -78,3 +78,3 @@ 'use strict';
 	if (method !== 'DELETE') {
-		req.write(this.registry.metrics({ timestamps: false }));
+		req.write(this.registry.metrics());
 	}
@@ -81,0 +81,0 @@ req.end();

lib/registry.js

@@ -14,9 +14,6 @@ 'use strict';
 
-const defaultMetricsOpts = {
-	timestamps: true
-};
-
 class Registry {
 	constructor() {
 		this._metrics = {};
+		this._collectors = [];
 		this._defaultLabels = {};
@@ -29,4 +26,3 @@ }
 
-	getMetricAsPrometheusString(metric, conf) {
-		const opts = Object.assign({}, defaultMetricsOpts, conf);
+	getMetricAsPrometheusString(metric) {
 		const item = metric.get();
@@ -45,7 +41,7 @@ const name = escapeString(item.name);
 				val.labels = Object.assign({}, val.labels);
-			}
 
-			for (const labelName of defaultLabelNames) {
-				val.labels[labelName] =
-					val.labels[labelName] || this._defaultLabels[labelName];
+				for (const labelName of defaultLabelNames) {
+					val.labels[labelName] =
+						val.labels[labelName] || this._defaultLabels[labelName];
+				}
 			}
@@ -63,7 +59,3 @@
 
-			let line = `${metricName} ${getValueAsString(val.value)}`;
-			if (opts.timestamps && val.timestamp) {
-				line += ` ${val.timestamp}`;
-			}
-			values += `${line.trim()}\n`;
+			values += `${metricName} ${getValueAsString(val.value)}\n`;
 		}
@@ -74,7 +66,9 @@
 
-	metrics(opts) {
+	metrics() {
 		let metrics = '';
 
+		this.collect();
+
 		for (const metric of this.getMetricsAsArray()) {
-			metrics += `${this.getMetricAsPrometheusString(metric, opts)}\n\n`;
+			metrics += `${this.getMetricAsPrometheusString(metric)}\n\n`;
 		}
@@ -85,17 +79,30 @@
 
-	registerMetric(metricFn) {
-		if (
-			this._metrics[metricFn.name] &&
-			this._metrics[metricFn.name] !== metricFn
-		) {
+	registerMetric(metric) {
+		if (this._metrics[metric.name] && this._metrics[metric.name] !== metric) {
 			throw new Error(
-				`A metric with the name ${metricFn.name} has already been registered.`
+				`A metric with the name ${metric.name} has already been registered.`
 			);
 		}
 
-		this._metrics[metricFn.name] = metricFn;
+		this._metrics[metric.name] = metric;
 	}
 
+	registerCollector(collectorFn) {
+		if (this._collectors.includes(collectorFn)) {
+			return; // Silently ignore repeated registration.
+		}
+		this._collectors.push(collectorFn);
+	}
+
+	collectors() {
+		return this._collectors;
+	}
+
+	collect() {
+		this._collectors.forEach(collector => collector());
+	}
+
 	clear() {
 		this._metrics = {};
+		this._collectors = [];
 		this._defaultLabels = {};
@@ -108,7 +115,12 @@ }
 
+		this.collect();
+
 		for (const metric of this.getMetricsAsArray()) {
 			const item = metric.get();
 
-			if (item.values) {
+			if (item.values && defaultLabelNames.length > 0) {
 				for (const val of item.values) {
+					// Make a copy before mutating
+					val.labels = Object.assign({}, val.labels);
+
 					for (const labelName of defaultLabelNames) {
@@ -115,0 +127,0 @@ val.labels[labelName] =

lib/summary.js

@@ -14,3 +14,2 @@ /**
 	isObject,
-	printDeprecationObjectConstructor,
 	removeLabels
@@ -30,45 +29,21 @@ } = require('./util');
 	 * Summary
-	 * @param {string} name - Name of the metric
-	 * @param {string} help - Help for the metric
-	 * @param {object|Array.<string>} labelsOrConf - Either array of label names or config object as a key-value object
-	 * @param {object} conf - Configuration object
+	 * @param {config} config - Configuration object.
+	 * @param {string} config.name - Name of the metric
+	 * @param {string} config.help - Help for the metric
+	 * @param {Array.<string>} config.labels - Array with strings, all label keywords supported
 	 */
-	constructor(name, help, labelsOrConf, conf) {
-		let config;
-		if (isObject(name)) {
-			config = Object.assign(
-				{
-					percentiles: [0.01, 0.05, 0.5, 0.9, 0.95, 0.99, 0.999],
-					labelNames: []
-				},
-				name
-			);
-
-			if (!config.registers) {
-				config.registers = [globalRegistry];
-			}
-		} else {
-			let obj;
-			let labels = [];
-
-			if (Array.isArray(labelsOrConf)) {
-				obj = conf || {};
-				labels = labelsOrConf;
-			} else {
-				obj = labelsOrConf || {};
-			}
-
-			printDeprecationObjectConstructor();
-
-			config = {
-				name,
-				help,
-				labelNames: labels,
-				percentiles: configurePercentiles(obj.percentiles),
-				registers: [globalRegistry],
-				maxAgeSeconds: obj.maxAgeSeconds,
-				ageBuckets: obj.ageBuckets
-			};
+	constructor(config) {
+		if (!isObject(config)) {
+			throw new TypeError('constructor expected a config object');
 		}
-
+		config = Object.assign(
+			{
+				percentiles: [0.01, 0.05, 0.5, 0.9, 0.95, 0.99, 0.999],
+				labelNames: []
+			},
+			config
+		);
+		if (!config.registers) {
+			config.registers = [globalRegistry];
+		}
 		validateInput(config.name, config.help, config.labelNames);
@@ -82,3 +57,2 @@
 		this.aggregator = config.aggregator || 'sum';
-
 		this.percentiles = config.percentiles;
@@ -237,13 +211,2 @@ this.hashMap = {};
 
-function configurePercentiles(configuredPercentiles) {
-	const defaultPercentiles = [0.01, 0.05, 0.5, 0.9, 0.95, 0.99, 0.999];
-	return []
-		.concat(configuredPercentiles || defaultPercentiles)
-		.sort(sortAscending);
-}
-
-function sortAscending(x, y) {
-	return x - y;
-}
-
 function observe(labels) {
@@ -250,0 +213,0 @@ return value => {

lib/util.js

 'use strict';
 
-const deprecationsEmitted = {};
-
-exports.isDate = isDate;
-
 exports.getPropertiesFromObj = function(hashMap) {
@@ -31,12 +27,7 @@ const obj = Object.keys(hashMap).map(x => hashMap[x]);
 
-exports.setValue = function setValue(hashMap, value, labels, timestamp) {
+exports.setValue = function setValue(hashMap, value, labels) {
 	const hash = hashObject(labels);
 	hashMap[hash] = {
 		value: typeof value === 'number' ? value : 0,
-		labels: labels || {},
-		timestamp: isDate(timestamp)
-			? timestamp.valueOf()
-			: Number.isFinite(timestamp)
-			? timestamp
-			: undefined
+		labels: labels || {}
 	};
@@ -83,5 +74,2 @@ return hashMap;
 
-function isDate(obj) {
-	return obj instanceof Date && !isNaN(obj.valueOf());
-}
 exports.isObject = function isObject(obj) {
@@ -91,30 +79,2 @@ return obj === Object(obj);
 
-function printDeprecation(msg) {
-	if (deprecationsEmitted[msg]) {
-		return;
-	}
-
-	deprecationsEmitted[msg] = true;
-
-	if (process.emitWarning) {
-		process.emitWarning(msg, 'DeprecationWarning');
-	} else {
-		// Check can be removed when we only support node@>=6
-		// eslint-disable-next-line no-console
-		console.warn(new Error(msg));
-	}
-}
-
-exports.printDeprecationObjectConstructor = () => {
-	printDeprecation(
-		'prom-client - Passing a non-object to metrics constructor is deprecated'
-	);
-};
-
-exports.printDeprecationCollectDefaultMetricsNumber = timeout => {
-	printDeprecation(
-		`prom-client - A number to defaultMetrics is deprecated, please use \`collectDefaultMetrics({ timeout: ${timeout} })\`.`
-	);
-};
-
 class Grouper extends Map {
@@ -121,0 +81,0 @@ /**

package.json

 {
-  "name": "prom-client",
-  "version": "11.5.3",
-  "description": "Client for prometheus",
-  "main": "index.js",
-  "files": [
-    "lib/",
-    "index.js",
-    "index.d.ts"
-  ],
-  "engines": {
-    "node": ">=6.1"
-  },
-  "scripts": {
-    "benchmarks": "node ./benchmarks/index.js",
-    "test": "npm run lint && npm run compile-typescript && npm run test-unit",
-    "lint": "eslint .",
-    "test-unit": "jest",
-    "compile-typescript": "tsc --project ."
-  },
-  "repository": {
-    "type": "git",
-    "url": "[e-mail]:siimon/prom-client.git"
-  },
-  "keywords": [
-    "Prometheus",
-    "Metrics",
-    "Client"
-  ],
-  "author": "Simon Nyberg",
-  "license": "Apache-2.0",
-  "homepage": "https://github.com/siimon/prom-client",
-  "devDependencies": {
-    "@clevernature/benchmark-regression": "^1.0.0",
-    "eslint": "^5.6.0",
-    "eslint-config-prettier": "^4.3.0",
-    "eslint-plugin-node": "^8.0.0",
-    "eslint-plugin-prettier": "^3.0.1",
-    "express": "^4.13.3",
-    "husky": "^1.3.1",
-    "jest": "^24.8.0",
-    "lint-staged": "^7.0.0",
-    "lolex": "^4.0.1",
-    "prettier": "1.17.1",
-    "typescript": "^3.0.3"
-  },
-  "dependencies": {
-    "tdigest": "^0.1.1"
-  },
-  "types": "./index.d.ts",
-  "jest": {
-    "testEnvironment": "node",
-    "testRegex": ".*Test\\.js$"
-  },
-  "lint-staged": {
-    "*.js": [
-      "eslint --fix",
-      "git add"
-    ],
-    "*.{ts,md,json,yml}": [
-      "prettier --write",
-      "git add"
-    ],
-    ".{eslintrc,travis.yml}": [
-      "prettier --write",
-      "git add"
-    ]
-  },
-  "prettier": {
-    "singleQuote": true,
-    "useTabs": true,
-    "overrides": [
-      {
-        "files": "*.md",
-        "options": {
-          "useTabs": false
-        }
-      },
-      {
-        "files": ".eslintrc",
-        "options": {
-          "parser": "json"
-        }
-      }
-    ]
-  },
-  "husky": {
-    "hooks": {
-      "pre-commit": "lint-staged"
-    }
-  }
+	"name": "prom-client",
+	"version": "12.0.0",
+	"description": "Client for prometheus",
+	"main": "index.js",
+	"files": [
+		"lib/",
+		"index.js",
+		"index.d.ts"
+	],
+	"engines": {
+		"node": ">=10"
+	},
+	"scripts": {
+		"benchmarks": "node ./benchmarks/index.js",
+		"test": "npm run lint && npm run compile-typescript && npm run test-unit",
+		"lint": "eslint .",
+		"test-unit": "jest",
+		"compile-typescript": "tsc --project ."
+	},
+	"repository": {
+		"type": "git",
+		"url": "[e-mail]:siimon/prom-client.git"
+	},
+	"keywords": [
+		"Prometheus",
+		"Metrics",
+		"Client"
+	],
+	"author": "Simon Nyberg",
+	"license": "Apache-2.0",
+	"homepage": "https://github.com/siimon/prom-client",
+	"devDependencies": {
+		"@clevernature/benchmark-regression": "^1.0.0",
+		"eslint": "^6.8.0",
+		"eslint-config-prettier": "^6.10.0",
+		"eslint-plugin-node": "^11.0.0",
+		"eslint-plugin-prettier": "^3.0.1",
+		"express": "^4.13.3",
+		"husky": "^4.2.1",
+		"jest": "^25.1.0",
+		"lint-staged": "^10.0.4",
+		"lolex": "^5.1.2",
+		"prettier": "1.19.1",
+		"typescript": "^3.0.3"
+	},
+	"dependencies": {
+		"tdigest": "^0.1.1"
+	},
+	"types": "./index.d.ts",
+	"jest": {
+		"testEnvironment": "node",
+		"testRegex": ".*Test\\.js$"
+	},
+	"lint-staged": {
+		"*.js": "eslint --fix",
+		"*.{ts,md,json,yml}": "prettier --write",
+		".{eslintrc,travis.yml}": "prettier --write"
+	},
+	"prettier": {
+		"singleQuote": true,
+		"useTabs": true,
+		"overrides": [
+			{
+				"files": "*.md",
+				"options": {
+					"useTabs": false
+				}
+			},
+			{
+				"files": ".eslintrc",
+				"options": {
+					"parser": "json"
+				}
+			}
+		]
+	},
+	"husky": {
+		"hooks": {
+			"pre-commit": "lint-staged"
+		}
+	}
 }

README.md

@@ -1,2 +0,2 @@
-# Prometheus client for node.js [![Build Status](https://travis-ci.org/siimon/prom-client.svg?branch=master)](https://travis-ci.org/siimon/prom-client) [![Build status](https://ci.appveyor.com/api/projects/status/k2e0gwonkcee3lp9/branch/master?svg=true)](https://ci.appveyor.com/project/siimon/prom-client/branch/master)
+# Prometheus client for node.js [![Build Status](https://travis-ci.org/siimon/prom-client.svg?branch=master)](https://travis-ci.org/siimon/prom-client) [![Build status](https://ci.appveyor.com/api/projects/status/k2e0gwonkcee3lp9/branch/master?svg=true)](https://ci.appveyor.com/project/siimon/prom-client/branch/master) [![Actions Status](https://github.com/siimon/prom-client/workflows/Node.js%20CI/badge.svg?branch=master)](https://github.com/siimon/prom-client/actions)
 
@@ -51,19 +51,12 @@ A prometheus client for node.js that supports histogram, summaries, gauges and
 In addition, some Node-specific metrics are included, such as event loop lag,
-active handles and Node.js version. See what metrics there are in
+active handles, GC and Node.js version. See what metrics there are in
 [lib/metrics](lib/metrics).
 
-`collectDefaultMetrics` takes 1 options object with 3 entries, a timeout for how
-often the probe should be fired, an optional prefix for metric names
-and a registry to which metrics should be registered. By default probes are
-launched every 10 seconds, but this can be modified like this:
+`collectDefaultMetrics` optionally accepts a config object with following entries:
 
-```js
-const client = require('prom-client');
+- `prefix` an optional prefix for metric names. Default: no prefix.
+- `registry` to which metrics should be registered. Default: the global default registry.
+- `gcDurationBuckets` with custom buckets for GC duration histogram. Default buckets of GC duration histogram are `[0.001, 0.01, 0.1, 1, 2, 5]` (in seconds).
+- `eventLoopMonitoringPrecision` with sampling rate in milliseconds. Must be greater than zero. Default: 10.
 
-const collectDefaultMetrics = client.collectDefaultMetrics;
-
-// Probe every 5th second.
-collectDefaultMetrics({ timeout: 5000 });
-```
-
 To register metrics to another registry, pass it in as `register`:
@@ -77,7 +70,6 @@
 const register = new Registry();
-
 collectDefaultMetrics({ register });
 ```
 
-To prefix metric names with your own arbitrary string, pass in a `prefix`:
+To use custom buckets for GC duration histogram, pass it in as `gcDurationBuckets`:
 
@@ -89,15 +81,12 @@ ```js
 
-// Probe every 5th second.
-collectDefaultMetrics({ prefix: 'my_application_' });
+collectDefaultMetrics({ gcDurationBuckets: [0.1, 0.2, 0.3] });
 ```
 
-To disable metric timestamps set `timestamps` to `false` (You can find the list of metrics that support this feature in `test/defaultMetricsTest.js`):
+To prefix metric names with your own arbitrary string, pass in a `prefix`:
 
 ```js
 const client = require('prom-client');
-
 const collectDefaultMetrics = client.collectDefaultMetrics;
-
-// Probe every 5th second.
-collectDefaultMetrics({ timestamps: false });
+const prefix = 'my_application_';
+collectDefaultMetrics({ prefix });
 ```
@@ -191,3 +180,3 @@
 The defaults buckets are intended to cover usual web/rpc requests, this can
-however be overriden.
+however be overridden.
 
@@ -231,3 +220,3 @@ ```js
 xhrRequest(function(err, res) {
-  end(); // Observes the value to xhrRequests duration in seconds
+  const seconds = end(); // Observes and returns the value to xhrRequests duration in seconds
 });
@@ -243,3 +232,3 @@ ```
 The default percentiles are: 0.01, 0.05, 0.5, 0.9, 0.95, 0.99, 0.999. But they
-can be overriden like this:
+can be overridden like this:
 
@@ -346,18 +335,2 @@ ```js
 
-### Timestamps
-
-Counter and gauge metrics can take a timestamp argument after the value
-argument. This argument must be a Date or a number (milliseconds since Unix
-epoch, i.e. 1970-01-01 00:00:00 UTC, excluding leap seconds).
-
-```js
-gauge.set(100, 1485531442231); // Set gauge value and timestamp as milliseconds since Unix epoch
-gauge.set(100, Date.now()); // Set gauge value and timestamp as milliseconds since Unix epoch
-gauge.set(100, new Date()); // Set gauge value and timestamp as Date
-gauge.set({ method: 'GET', statusCode: '200' }, 100, new Date()); // Set gauge value and timestamp with labels
-gauge.labels('GET', '200').set(100, new Date()); // Same as above
-
-counter.inc(1, new Date()); // Increment counter with timestamp
-```
-
 ### Multiple registries
@@ -412,5 +385,2 @@
 
-`register.metrics()` takes an optional object with a `timestamps` field. Setting
-this to false will strip timestamps from the string.
-
 #### Getting a single metric for Prometheus displaying
@@ -467,5 +437,2 @@
 
-Note that timestamps will be stripped before the metrics are pushed, since
-pushgateway >= 0.4 does not accept timestamps.
-
 ```js
@@ -490,3 +457,3 @@ const client = require('prom-client');
 
-### Utilites
+### Utilities
 
@@ -493,0 +460,0 @@ For convenience, there are 2 bucket generator functions - linear and

New alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Debug access

Supply chain risk

Uses debug, reflection and dynamic code execution features.

Found 1 instance in 1 package

Fixed alerts

License Policy Violation

License

This package is not allowed per your license policy. Review the package's license to ensure compliance.

Found 1 instance in 1 package

Improved metrics

Number of package files

34

increased by3.03%

Worsened metrics

Total package byte prevSize

111968

decreased by-1.25%

Lines of code

2653

decreased by-5.15%

Number of lines in readme file

475

decreased by-6.5%

Number of low supply chain risk alerts

6

increased by50%

No dependency changes