CompositeCounters

Implements: ICounters, IReconfigurable, ICounterTimingCallback

Description

The CompositeCounters allows you to aggregate all counters from different component references into a single one.

Important points

• It allows to capture metrics and conveniently send them to multiple destinations.

References

• *:counters:*:*:1.0 - (optional) ICounters components to pass collected measurements

Constructors

Creates a new instance of the counters.

public constructor(references: IReferences = null)

• references: IReferences - references to locate the component dependencies.

Fields

Instance methods

beginTiming

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.

public beginTiming(name: string): CounterTiming

• name: string - a counter name of Interval type.
• returns: CounterTiming - a callback object to end timing.

endTiming

Ends measurement of execution elapsed time and updates specified counter.

public endTiming(name: string, elapsed: number): void

• name: string - a counter name
• elapsed: number - execution elapsed time in milliseconds to update the counter.

increment

Increments counter by given value.

public increment(name: string, value: number): void

• name: string - a counter name of Increment type.
• value: number - a value to add to the counter.

incrementOne

Increments counter by 1.

public incrementOne(name: string): void

• name: string - a counter name of Increment type.

last

Records the last calculated measurement value. Usually this method is used by metrics calculated externally.

public last(name: string, value: number): void

• name: string - a counter name of Last type.
• value: number - last value to record.

setReferences

Sets references to dependent components.

public setReferences(references: IReferences): void

• references: IReferences - references to locate the component dependencies.

stats

Calculates min/average/max statistics based on the current and previous values.

public stats(name: string, value: number): void

• name: string - a counter name of Statistics type
• value: number - a value to update statistics

timestamp

Records the given timestamp.

public timestamp(name: string, value: Date)

• name: string - a counter name of Timestamp type.
• value: Date - a timestamp to record.

timestampNow

Records the current time as a timestamp.

public timestampNow(name: string)

• name: string - a counter name of Timestamp type.

Examples

class MyComponent implements IReferenceable {
    private _counters: CompositeCounters = new CompositeCounters();

    public setReferences(references: IReferences): void {
        this._counters.setReferences(references);
        ...
    }

    public myMethod(): void {
        this._counters.increment("mycomponent.mymethod.calls");
        var timing = this._counters.beginTiming("mycomponent.mymethod.exec_time");
        try {
            ...
        } finally {
            timing.endTiming();
        }
    }
}

See also

• ICounters