frequency-counter

frequency-counter

Count the number of occurrences of a repeating event per unit of time.

Installation

npm install frequency-counter --save

Usage example

Example HTTP server responding with the number of requests per minute (rpm):

const http = require('http')
const Freq = require('frequency-counter')

// if no arguments are given a window of one minute is used
const counter = new Freq()

const server = http.createServer(function (req, res) {
  // increment the count
  counter.inc()
 
  // return current frequency to client
  res.end('rpm: ' + counter.freq() + '\n')
})

server.listen(3000)

API

counter = new Freq([windowSize])

Initialize the frequency counter. Optionally set a custom window size in seconds over which the frequency should be calcuated (default: 60).

counter.inc([amount])

Track an occurrence by incrementing a counter. Optionally provide the amount to increment by (default: 1).

number = counter.freq()

Calculate and return the current frequency.

License

MIT