ms-perf

Node.js inline function performance measurement tool.
Provides simple way to understand how much relative time your functions/promises are being executed for

install

npm i ms-perf -S

usage

Module generally consists of a single function with different use

1. start timer instance

``js
const perf = require('ms-perf');

// pass in timer name
const timer = perf('timer-name');
`

2. register timer triggers

`js
// returns Function
timer('trigger')
`

3. retrieve timers

`js
// returns reference to timers object
// and cleans up internal context
timer()
`

$3

`js
// bluebird has many useful utilities...
const Promise = require('bluebird');
const perf = require('ms-perf');
const rethrow = e => {
throw e
};

function asyncExecutionFlow(input) {
const timer = perf('async');

return Promise
.resolve(input)
.then(doHTTPRequest)
// please do not use '$' as this is a reserved character for total
// for performance reasons there is no check on the input argument
.tap(timer('http'))
.then(processHTTPRequest)
.tap(timer('parse'))
.then(parsed => ({
meta: {},
data: parsed
}))
.catch(e => {
// ensure that in-case of errors timer is cancelled
const timers = timer();
// do something with error timers / handle errors
throw e;
})
.tap((data) => {
data.meta.timers = timer();
})
.tap(console.log)

// when promise is completed, output will look like this:
//
// {
// meta: {
// timers: {
// 'async:http': 321,
// 'async:parse': 1.21,
// 'async:$': 323.30
// }
// },
// data: {
// ...whatever was inside parsed
// }
// }
}
``