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Flexible ascii progress bar.
## Installation
```bash $ 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.
```javascript 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.
```javascript 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.
```javascript 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()` ```javascript 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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