progress

What is progress?

The 'progress' npm package is used to create a flexible text progress bar in the console. It is useful for tracking the progress of an operation in command-line applications.

What are progress's main functionalities?

Basic Progress Bar

This code sample demonstrates how to create a simple progress bar that updates every 100 milliseconds until it's complete.

const ProgressBar = require('progress');

let bar = new ProgressBar(':bar', { total: 10 });
let timer = setInterval(() => {
  bar.tick();
  if (bar.complete) {
    console.log('\nComplete!');
    clearInterval(timer);
  }
}, 100);

Custom Tokens

This code sample shows how to use custom tokens within the progress bar format to display additional information.

const ProgressBar = require('progress');

let bar = new ProgressBar(':current/:total (:percent) :bar :custom', { total: 20, width: 30 });
bar.tick({ custom: 'Token' });

Increment with Step

This code sample illustrates how to increment the progress bar by a step greater than one.

const ProgressBar = require('progress');

let bar = new ProgressBar(':bar', { total: 10 });
bar.tick(2);

Other packages similar to progress

cli-progress

cli-progress is a full-featured progress bar for Node.js command line applications. It offers more customization options than 'progress', such as multiple bars, custom bar characters, and payload handling.

nanobar

nanobar is a very lightweight progress bar without jQuery. While it is not directly comparable to 'progress' since it's for browser use, it serves a similar purpose in providing visual feedback for progress in a minimalistic way.

node-progress-bars

node-progress-bars is another alternative to 'progress' that allows for multiple simultaneous progress bars in the terminal. It provides a different API and additional features like color support.

README

Flexible ascii progress bar.

Installation

$ npm install progress

Usage

First we create a ProgressBar, giving it a format string as well as the total, telling the progress bar when it will be considered complete. After that all we need to do is tick() appropriately.

var ProgressBar = require('progress');

var bar = new ProgressBar(':bar', { total: 10 });
var timer = setInterval(function () {
  bar.tick();
  if (bar.complete) {
    console.log('\ncomplete\n');
    clearInterval(timer);
  }
}, 100);

Options

These are keys in the options object you can pass to the progress bar along with total as seen in the example above.

• curr current completed index
• total total number of ticks to complete
• width the displayed width of the progress bar defaulting to total
• stream the output stream defaulting to stderr
• head head character defaulting to complete character
• complete completion character defaulting to "="
• incomplete incomplete character defaulting to "-"
• renderThrottle minimum time between updates in milliseconds defaulting to 16
• clear option to clear the bar on completion defaulting to false
• callback optional function to call when the progress bar completes

Tokens

These are tokens you can use in the format of your progress bar.

• :bar the progress bar itself
• :current current tick number
• :total total ticks
• :elapsed time elapsed in seconds
• :percent completion percentage
• :eta estimated completion time in seconds
• :rate rate of ticks per second

Custom Tokens

You can define custom tokens by adding a {'name': value} object parameter to your method (tick(), update(), etc.) calls.

var bar = new ProgressBar(':current: :token1 :token2', { total: 3 })
bar.tick({
  'token1': "Hello",
  'token2': "World!\n"
})
bar.tick(2, {
  'token1': "Goodbye",
  'token2': "World!"
})

The above example would result in the output below.

1: Hello World!
3: Goodbye World!

Examples

Download

In our download example each tick has a variable influence, so we pass the chunk length which adjusts the progress bar appropriately relative to the total length.

var ProgressBar = require('progress');
var https = require('https');

var req = https.request({
  host: 'download.github.com',
  port: 443,
  path: '/visionmedia-node-jscoverage-0d4608a.zip'
});

req.on('response', function(res){
  var len = parseInt(res.headers['content-length'], 10);

  console.log();
  var bar = new ProgressBar('  downloading [:bar] :rate/bps :percent :etas', {
    complete: '=',
    incomplete: ' ',
    width: 20,
    total: len
  });

  res.on('data', function (chunk) {
    bar.tick(chunk.length);
  });

  res.on('end', function () {
    console.log('\n');
  });
});

req.end();

The above example result in a progress bar like the one below.

downloading [=====             ] 39/bps 29% 3.7s

Interrupt

To display a message during progress bar execution, use interrupt()

var ProgressBar = require('progress');

var bar = new ProgressBar(':bar :current/:total', { total: 10 });
var timer = setInterval(function () {
  bar.tick();
  if (bar.complete) {
    clearInterval(timer);
  } else if (bar.curr === 5) {
      bar.interrupt('this message appears above the progress bar\ncurrent progress is ' + bar.curr + '/' + bar.total);
  }
}, 1000);

You can see more examples in the examples folder.

License

MIT