.eslintrc

@@ -62,7 +62,7 @@
 			}
 		},
 		{
-			"files": ["example/**/*.js"],
+			"files": ["example/**/*.js","benchmarks/**/*.js"],
 			"rules": {
 				"no-console": "off"
 			}

CHANGELOG.md

@@ -13,177 +13,188 @@ project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
+## [11.2.0]
+
+### Changed
+
+* Updated child dependency `merge` patch version to remove vulnerability.
+
+### Added
+
+* Added an initial `benchmark` suite which can be run with `npm run benchmarks`.
+* Add support for sliding windows in Summaries
+
 ## [11.1.3] - 2018-09-22
 
 ### Changed
 
-- Fixed performance by avoiding `Object.assign` on hot paths, as well as
+* Fixed performance by avoiding `Object.assign` on hot paths, as well as
   mutating objects when appropriate.
 
 ## [11.1.2] - 2018-09-19
 
 ### Changed
 
-- Allow setting Gauge values to NaN, +Inf, and -Inf
-- Fixed `histogram` scrape performance by using `acc.push` instead of `acc.concat`. Fixes #216 with #219
+* Allow setting Gauge values to NaN, +Inf, and -Inf
+* Fixed `histogram` scrape performance by using `acc.push` instead of `acc.concat`. Fixes #216 with #219
 
 ## [11.1.1] - 2018-06-29
 
 ### Changed
 
-- Fixed `processOpenFileDescriptors` metric when no custom config was set
+* Fixed `processOpenFileDescriptors` metric when no custom config was set
 
 ## [11.1.0] - 2018-06-29
 
-- Added ability to set a name prefix in the default metrics
+* Added ability to set a name prefix in the default metrics
 
 ### Changed
 
-- Fixed `startTimer` utility to not mutate objects passed as `startLabels`
-- Fixed `Counter` to validate labels parameter of `inc()` against initial
+* Fixed `startTimer` utility to not mutate objects passed as `startLabels`
+* Fixed `Counter` to validate labels parameter of `inc()` against initial
   labelset
-- Fixed `AggregatorFactory` losing the aggregator method of metrics
+* Fixed `AggregatorFactory` losing the aggregator method of metrics
 
 ## [11.0.0] - 2018-03-10
 
 ### Breaking
 
-- Fixed `gauge.setToCurrentTime()` to use seconds instead of milliseconds
-  - This conforms to Prometheus
+* Fixed `gauge.setToCurrentTime()` to use seconds instead of milliseconds
+  * This conforms to Prometheus
     [best practices](https://prometheus.io/docs/practices/naming/#base-units)
-- Dropped support for node 4
+* Dropped support for node 4
 
 ## [10.2.3] - 2018-02-28
 
 ### Breaking
 
 ### Changed
 
-- Fixed issue that `registry.getMetricsAsJSON()` ignores registry default labels
+* Fixed issue that `registry.getMetricsAsJSON()` ignores registry default labels
 
 ### Added
 
 ## [10.2.2] - 2017-11-02
 
 ### Changed
 
-- Fixed invalid `process_virtual_memory_bytes` reported under linux
+* Fixed invalid `process_virtual_memory_bytes` reported under linux
 
 ## [10.2.1] - 2017-10-27
 
 ### Changed
 
-- Only resolve/reject `clusterMetrics` promise if no callback is provided
+* Only resolve/reject `clusterMetrics` promise if no callback is provided
 
 ## [10.2.0] - 2017-10-16
 
 ### Changed
 
-- Don't add event listeners if cluster module is not used.
-- Fixed issue with counters having extra records when using empty labels
+* Don't add event listeners if cluster module is not used.
+* Fixed issue with counters having extra records when using empty labels
 
 ### Added
 
-- Added `reset` to Counter and Gauge
-- Added `resetMetrics` to register to calling `reset` of all metric instances
+* Added `reset` to Counter and Gauge
+* Added `resetMetrics` to register to calling `reset` of all metric instances
 
 ## [10.1.1] - 2017-09-26
 
 ### Changed
 
-- Update TypeScript definitions and JSDoc comments to match JavaScript sources
-- Fix lexical scope of `arguments` in cluster code
+* Update TypeScript definitions and JSDoc comments to match JavaScript sources
+* Fix lexical scope of `arguments` in cluster code
 
 ## [10.1.0] - 2017-09-04
 
 ### Added
 
-- Support aggregating metrics across workers in a Node.js cluster.
+* Support aggregating metrics across workers in a Node.js cluster.
 
 ## [10.0.4] - 2017-08-22
 
 ### Changed
 
-- Include invalid values in the error messages
+* Include invalid values in the error messages
 
 ## [10.0.3] - 2017-08-07
 
 ### Added
 
-- Added registerMetric to definitions file
+* Added registerMetric to definitions file
 
 ### Changed
 
-- Fixed typing of DefaultMetricsCollectorConfiguration in definitions file
-- Don't pass timestamps through to pushgateway by default
+* Fixed typing of DefaultMetricsCollectorConfiguration in definitions file
+* Don't pass timestamps through to pushgateway by default
 
 ## [10.0.2] - 2017-07-07
 
 ### Changed
 
-- Don't poll default metrics every single tick
+* Don't poll default metrics every single tick
 
 ## [10.0.1] - 2017-07-06
 
 ### Added
 
-- Metrics should be initialized to 0 when there are no labels
+* Metrics should be initialized to 0 when there are no labels
 
 ## [10.0.0] - 2017-07-04
 
 ### Breaking
 
-- Print deprecation warning when metrics are constructed using non-objects
-- Print deprecation warning when `collectDefaultMetrics` is called with a number
+* Print deprecation warning when metrics are constructed using non-objects
+* Print deprecation warning when `collectDefaultMetrics` is called with a number
 
 ### Added
 
-- Ability to set default labels by registry
-- Allow passing in `registry` as second argument to `collectDefaultMetrics` to
+* Ability to set default labels by registry
+* Allow passing in `registry` as second argument to `collectDefaultMetrics` to
   use that instead of the default registry
 
 ### Changed
 
-- Convert code base to ES2015 code (node 4)
-  - add engines field to package.json
-  - Use object shorthand
-  - Remove `util-extend` in favor of `Object.assign`
-  - Arrow functions over binding or putting `this` in a variable
-  - Use template strings
-  - `prototype` -> `class`
+* Convert code base to ES2015 code (node 4)
+  * add engines field to package.json
+  * Use object shorthand
+  * Remove `util-extend` in favor of `Object.assign`
+  * Arrow functions over binding or putting `this` in a variable
+  * Use template strings
+  * `prototype` -> `class`
 
 ## [9.1.1] - 2017-06-17
 
 ### Changed
 
-- Don't set timestamps for metrics that are never updated
+* Don't set timestamps for metrics that are never updated
 
 ## [9.1.0] - 2017-06-07
 
 ### Added
 
-- Ability to merge registries
+* Ability to merge registries
 
 ### Changed
 
-- Correct typedefs for object constructor of metrics
+* Correct typedefs for object constructor of metrics
 
 ## [9.0.0] - 2017-05-06
 
 ### Added
 
-- Support for multiple registers
-- Support for object literals in metric constructors
-- Timestamp support
+* Support for multiple registers
+* Support for object literals in metric constructors
+* Timestamp support
 
 ### Changed
 
-- Collection of default metrics is now disabled by default. Start collection by
+* Collection of default metrics is now disabled by default. Start collection by
   running `collectDefaultMetrics()`.
 
 ### Deprecated
 
-- Creating metrics with one argument per parameter - use object literals
+* Creating metrics with one argument per parameter - use object literals
   instead.
 
 [unreleased]: https://github.com/siimon/prom-client/compare/v10.2.2...HEAD

README.md

@@ -258,6 +258,23 @@ new client.Summary({
 });
 ```
 
+To enable the sliding window functionality for summaries you need to add
+`maxAgeSeconds` and `ageBuckets` to the config like this:
+
+```js
+const client = require('prom-client');
+new client.Summary({
+  name: 'metric_name',
+  help: 'metric_help',
+  maxAgeSeconds: 600,
+  ageBuckets: 5
+});
+```
+
+The `maxAgeSeconds` will tell how old an bucket can be before it is reset and
+`ageBuckets` configures how many buckets we will have in our sliding window for
+the summary.
+
 Usage example
 
 ```js

benchmarks/histogram.js

@@ -0,0 +1,67 @@
+'use strict';
+
+const { getLabelNames, labelCombinationFactory } = require('./utils/labels');
+
+module.exports = setupHistogramSuite;
+
+function setupHistogramSuite(suite) {
+	suite.add(
+		'observe#1 with 64',
+		labelCombinationFactory([64], (client, { histogram }, labels) =>
+			histogram.observe(labels, 1)
+		),
+		{ teardown, setup: setup(1) }
+	);
+
+	suite.add(
+		'observe#2 with 8',
+		labelCombinationFactory([8, 8], (client, { histogram }, labels) =>
+			histogram.observe(labels, 1)
+		),
+		{ teardown, setup: setup(2) }
+	);
+
+	suite.add(
+		'observe#2 with 4 and 2 with 2',
+		labelCombinationFactory([4, 4, 2, 2], (client, { histogram }, labels) =>
+			histogram.observe(labels, 1)
+		),
+		{ teardown, setup: setup(4) }
+	);
+
+	suite.add(
+		'observe#2 with 2 and 2 with 4',
+		labelCombinationFactory([2, 2, 4, 4], (client, { histogram }, labels) =>
+			histogram.observe(labels, 1)
+		),
+		{ teardown, setup: setup(4) }
+	);
+
+	suite.add(
+		'observe#6 with 2',
+		labelCombinationFactory(
+			[2, 2, 2, 2, 2, 2],
+			(client, { histogram }, labels) => histogram.observe(labels, 1)
+		),
+		{ teardown, setup: setup(6) }
+	);
+}
+
+function setup(labelCount) {
+	return client => {
+		const registry = new client.Registry();
+
+		const histogram = new client.Histogram({
+			name: 'histogram',
+			help: 'histogram',
+			labelNames: getLabelNames(labelCount),
+			registers: [registry]
+		});
+
+		return { registry, histogram };
+	};
+}
+
+function teardown(client, { registry }) {
+	registry.clear();
+}

benchmarks/index.js

@@ -0,0 +1,16 @@
+'use strict';
+
+const createRegressionBenchmark = require('@clevernature/benchmark-regression');
+
+const currentClient = require('..');
+const benchmarks = createRegressionBenchmark(currentClient, [
+	'prom-client@latest'
+]);
+
+benchmarks.suite('registry', require('./registry'));
+benchmarks.suite('histogram', require('./histogram'));
+benchmarks.run().catch(err => {
+	console.error(err.stack);
+	// eslint-disable-next-line no-process-exit
+	process.exit(1);
+});