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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

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