pip-services3-components-node/src/count/NullCounters.ts

Component definitions for Pip.Services in Node.js

/** @module count */
import { CounterTiming } from './CounterTiming';
import { ICounters } from './ICounters';

/**
 * Dummy implementation of performance counters that doesn't do anything.
 * 
 * It can be used in testing or in situations when counters is required
 * but shall be disabled.
 * 
 * @see [[ICounters]]
 */
export class NullCounters implements ICounters {

	/**
	 * Creates a new instance of the counter.
	 */
	public constructor() { }

	/**
	 * Begins measurement of execution time interval.
	 * It returns [[CounterTiming]] object which has to be called at
	 * [[CounterTiming.endTiming]] to end the measurement and update the counter.
	 * 
	 * @param name 	a counter name of Interval type.
	 * @returns a [[CounterTiming]] callback object to end timing.
     */
	public beginTiming(name: string): CounterTiming {
		return new CounterTiming();
	}

	/**
	 * Calculates min/average/max statistics based on the current and previous values.
	 * 
	 * @param name 		a counter name of Statistics type
	 * @param value		a value to update statistics
	 */
	public stats(name: string, value: number): void { }

	/**
	 * Records the last calculated measurement value.
	 * 
	 * Usually this method is used by metrics calculated
	 * externally.
	 * 
	 * @param name 		a counter name of Last type.
	 * @param value		a last value to record.
	 */
	public last(name: string, value: number): void { }

	/**
	 * Records the current time as a timestamp.
	 * 
	 * @param name 		a counter name of Timestamp type.
	 */
	public timestampNow(name: string): void { }

	/**
	 * Records the given timestamp.
	 * 
	 * @param name 		a counter name of Timestamp type.
	 * @param value		a timestamp to record.
	 */
	public timestamp(name: string, value: Date): void { }

	/**
	 * Increments counter by 1.
	 * 
	 * @param name 		a counter name of Increment type.
	 */
	public incrementOne(name: string): void { }

	/**
	 * Increments counter by given value.
	 * 
	 * @param name 		a counter name of Increment type.
	 * @param value		a value to add to the counter.
	 */
	public increment(name: string, value: number): void { }
}