js-rrd

js-rrd

A Javascript in memory Round Robin Database (RRD).

Inspired by rrdtool but not quite the same.

Install

npm install js-rrd

API

function create( timeUnits, count, bucketFunction )

timeUnits - Time units of each bucket.
	Valid values:
		sec
		min
		hr
		day
		week

count - Number of buckets of each timeUnit.

bucketFunction - Function applied to data added to bucket.
	Current functions:
		count - Count each time bucket is updated.
		last - Last value written to bucket.
		sum - Sum of all values written to bucket.
		avg - Average of all values written to bucket.

function update( data )

data - Data to add to current bucket.

function fetch()

Return array of buckets.

function stop()

Stop incrementing to next bucket when timeUnit ends.

Example

// Create a DB
// Use 1 second buckets for 10 seconds, sum all data added.
const jsrrd = require( 'js-rrd' );
 
var sixtySecondSums = jsrrd.create( 'sec', 10, 'sum' );
console.dir( sixtySecondSums.update );
 
// Add data to the RRD.
sixtySecondSums.update( 10 );
sixtySecondSums.update( 20 );
sixtySecondSums.update( 30 );
 
// After 2 seconds fetch the RRD and display it.
setTimeout( function() {
    // Get the last 10 seconds of the RRD.
    var now = sixtySecondSums.fetch();
 
    // Display it.
    console.dir( now );
    sixtySecondSums.stop();
}, 2000 );