cli-progress

What is cli-progress?

The cli-progress package is a versatile library for Node.js designed to create customizable progress bars in the command line interface (CLI). It supports various styles, custom tokens, and can handle multiple bars simultaneously, making it suitable for applications that require real-time progress feedback.

What are cli-progress's main functionalities?

Single Progress Bar

This demonstrates how to create a simple progress bar that updates from 0 to 50 out of 100. It uses the 'shades_classic' preset for styling.

const cliProgress = require('cli-progress');
const bar = new cliProgress.SingleBar({}, cliProgress.Presets.shades_classic);
bar.start(100, 0);
bar.update(50);
bar.stop();

Multiple Progress Bars

This example shows how to manage multiple progress bars simultaneously. It creates two bars with different total values and updates them independently.

const cliProgress = require('cli-progress');
const multiBar = new cliProgress.MultiBar({ clearOnComplete: false, hideCursor: true }, cliProgress.Presets.shades_grey);
const bar1 = multiBar.create(200, 0);
const bar2 = multiBar.create(100, 0);
bar1.increment();
bar2.update(20);
multiBar.stop();

Custom Tokens

This code snippet illustrates how to use custom tokens within the progress bar format. It displays additional information like speed alongside the progress.

const cliProgress = require('cli-progress');
const customBar = new cliProgress.SingleBar({ format: 'Progress |{bar}| {percentage}% || {value}/{total} Chunks || Speed: {speed}' }, cliProgress.Presets.shades_classic);
customBar.start(100, 0, { speed: 'N/A' });
customBar.update(40, { speed: '4MB/s' });
customBar.stop();

Other packages similar to cli-progress

progress

The 'progress' package offers a simpler, more streamlined approach to progress bars in Node.js. While it lacks some of the advanced features and customization options of cli-progress, it's a solid choice for basic needs.

nanobar

Nanobar is primarily focused on creating lightweight progress bars for web applications. Unlike cli-progress, which is designed for CLI applications, Nanobar is for frontend development, showcasing the versatility in application contexts.

progressbar.js

progressbar.js provides a more visually rich set of progress bars for web applications, including circular progress bars and other shapes. It's more suited for graphical interfaces compared to cli-progress, which is tailored for CLI environments.

README

Single Bar | Multi Bar | Options | Examples | Presets | Events

CLI-Progress

easy to use progress-bar for command-line/terminal applications

Install

$ yarn add cli-progress
$ npm install cli-progress --save

Features

• Simple, Robust and Easy to use
• Full customizable output format (various placeholders are available)
• Single progressbar mode
• Multi progessbar mode
• Custom Bar Characters
• FPS limiter
• ETA calculation based on elapsed time
• Custom Tokens to display additional data (payload) within the bar
• TTY and NOTTY mode
• No callbacks required - designed as pure, external controlled UI widget
• Works in Asynchronous and Synchronous tasks
• Preset/Theme support
• Custom bar formatters (via callback)
• Logging during multibar operation

Usage

Multiple examples are available e.g. example.js - just try it $ node example.js

const cliProgress = require('cli-progress');

// create a new progress bar instance and use shades_classic theme
const bar1 = new cliProgress.SingleBar({}, cliProgress.Presets.shades_classic);

// start the progress bar with a total value of 200 and start value of 0
bar1.start(200, 0);

// update the current value in your application..
bar1.update(100);

// stop the progress bar
bar1.stop();

Single Bar Mode

Example

const cliProgress = require('cli-progress');

// note: you have to install this dependency manually since it's not required by cli-progress
const colors = require('ansi-colors');

// create new progress bar
const b1 = new cliProgress.SingleBar({
    format: 'CLI Progress |' + colors.cyan('{bar}') + '| {percentage}% || {value}/{total} Chunks || Speed: {speed}',
    barCompleteChar: '\u2588',
    barIncompleteChar: '\u2591',
    hideCursor: true
});

// initialize the bar - defining payload token "speed" with the default value "N/A"
b1.start(200, 0, {
    speed: "N/A"
});

// update values
b1.increment();
b1.update(20);

// stop the bar
b1.stop();

Constructor

Initialize a new Progress bar. An instance can be used multiple times! it's not required to re-create it!

const cliProgress = require('cli-progress');

const <instance> = new cliProgress.SingleBar(options:object [, preset:object]);

Options

::start()

Starts the progress bar and set the total and initial value

<instance>.start(totalValue:int, startValue:int [, payload:object = {}]);

::update()

Sets the current progress value and optionally the payload with values of custom tokens as a second parameter. To update payload only, set currentValue to null.

<instance>.update([currentValue:int [, payload:object = {}]]);

// update progress without altering value
<instance>.update([payload:object = {}]);

::increment()

Increases the current progress value by a specified amount (default +1). Update payload optionally

<instance>.increment([delta:int [, payload:object = {}]]);

// delta=1 assumed
<instance>.increment(payload:object = {}]);

::setTotal()

Sets the total progress value while progressbar is active. Especially useful handling dynamic tasks.

<instance>.setTotal(totalValue:int);

::stop()

Stops the progress bar and go to next line

<instance>.stop();

::updateETA()

Force eta calculation update (long running processes) without altering the progress values.

Note: you may want to increase etaBuffer size - otherwise it can cause INF eta values in case the value didn't changed within the time series.

<instance>.updateETA();

Multi Bar Mode

Example

const cliProgress = require('cli-progress');

// create new container
const multibar = new cliProgress.MultiBar({
    clearOnComplete: false,
    hideCursor: true,
    format: ' {bar} | {filename} | {value}/{total}',
}, cliProgress.Presets.shades_grey);

// add bars
const b1 = multibar.create(200, 0);
const b2 = multibar.create(1000, 0);

// control bars
b1.increment();
b2.update(20, {filename: "test1.txt"});
b1.update(20, {filename: "helloworld.txt"});

// stop all bars
multibar.stop();

Constructor

Initialize a new multiprogress container. Bars need to be added. The options/presets are used for each single bar!

const cliProgress = require('cli-progress');

const <instance> = new cliProgress.MultiBar(options:object [, preset:object]);

::create()

Adds a new progress bar to the container and starts the bar. Returns regular SingleBar object which can be individually controlled.

Additional barOptions can be passed directly to the generic-bar to override the global options for a single bar instance. This can be useful to change the appearance of a single bar object. But be patient: this should only be used to override formats - DON'T try to set other global options like the terminal, synchronous flags, etc..

const <barInstance> = <instance>.create(totalValue:int, startValue:int [, payload:object = {} [, barOptions:object = {}]]);

::remove()

Removes an existing bar from the multi progress container.

<instance>.remove(<barInstance>:object);

::stop()

Stops the all progress bars

<instance>.stop();

::log()

Outputs (buffered) content on top of the multibars during operation.

Notice: newline at the end is required

Example: example-logging.js

<instance>.log("Hello World\n");

Options

The following options can be changed

• format (type:string|function) - progress bar output format @see format section
• fps (type:float) - the maximum update rate (default: 10)
• stream (type:stream) - output stream to use (default: process.stderr)
• stopOnComplete (type:boolean) - automatically call stop() when the value reaches the total (default: false)
• clearOnComplete (type:boolean) - clear the progress bar on complete / stop() call (default: false)
• barsize (type:int) - the length of the progress bar in chars (default: 40)
• align (type:char) - position of the progress bar - 'left' (default), 'right' or 'center'
• barCompleteChar (type:char) - character to use as "complete" indicator in the bar (default: "=")
• barIncompleteChar (type:char) - character to use as "incomplete" indicator in the bar (default: "-")
• hideCursor (type:boolean) - hide the cursor during progress operation; restored on complete (default: false) - pass null to keep terminal settings
• linewrap (type:boolean) - disable line wrapping (default: false) - pass null to keep terminal settings; pass true to add linebreaks automatically (not recommended)
• gracefulExit (type:boolean) - stop the bars in case of SIGINT or SIGTERM - this restores most cursor settings before exiting (default: true)
• etaBuffer (type:int) - number of updates with which to calculate the eta; higher numbers give a more stable eta (default: 10)
• etaAsynchronousUpdate (type:boolean) - trigger an eta calculation update during asynchronous rendering trigger using the current value - should only be used for long running processes in conjunction with lof fps values and large etaBuffer (default: false)
• progressCalculationRelative (type:boolean) - progress calculation uses startValue as zero-offset (default: false)
• synchronousUpdate (type:boolean) - trigger redraw during update() in case threshold time x2 is exceeded (default: true) - limited to single bar usage
• noTTYOutput (type:boolean) - enable scheduled output to notty streams - e.g. redirect to files (default: false)
• notTTYSchedule (type:int) - set the output schedule/interval for notty output in ms (default: 2000ms)
• emptyOnZero (type:boolean) - display progress bars with 'total' of zero(0) as empty, not full (default: false)
• forceRedraw (type:boolean) - trigger redraw on every frame even if progress remains the same; can be useful if progress bar gets overwritten by other concurrent writes to the terminal (default: false)
• barGlue (type:string) - a "glue" string between the complete and incomplete bar elements used to insert ascii control sequences for colorization (default: empty) - Note: in case you add visible "glue" characters the barsize will be increased by the length of the glue!
• autopadding (type: boolean) - add padding chars to formatted time and percentage to force fixed width (default: false) - Note: handled standard format functions!
• autopaddingChar (type: string) - the character sequence used for autopadding (default: " ") - Note: due to performance optimizations this value requires a length of 3 identical chars
• formatBar (type: function) - a custom bar formatter function which renders the bar-element (default: format-bar.js)
• formatTime (type: function) - a custom timer formatter function which renders the formatted time elements like eta_formatted and duration-formatted (default: format-time.js)
• formatValue (type: function) - a custom value formatter function which renders all other values (default: format-value.js)

Events

The classes extends EventEmitter which allows you to hook into different events.

See event docs for detailed information + examples.

Bar Formatting

The progressbar can be customized by using the following build-in placeholders. They can be combined in any order.

• {bar} - the progress bar, customizable by the options barsize, barCompleteString and barIncompleteString
• {percentage} - the current progress in percent (0-100)
• {total} - the end value
• {value} - the current value set by last update() call
• {eta} - expected time of accomplishment in seconds (limmited to 115days, otherwise INF is displayed)
• {duration} - elapsed time in seconds
• {eta_formatted} - expected time of accomplishment formatted into appropriate units
• {duration_formatted} - elapsed time formatted into appropriate units
• {<payloadKeyName>} - the payload value identified by its key

Example

const opt = {
    format: 'progress [{bar}] {percentage}% | ETA: {eta}s | {value}/{total}'
}

is rendered as

progress [========================================] 100% | ETA: 0s | 200/200

Custom formatters

Instead of a "static" format string it is also possible to pass a custom callback function as formatter. For a full example (including params) take a look on lib/formatter.js

Example 1

function formatter(options, params, payload){

    // bar grows dynamically by current progress - no whitespaces are added
    const bar = options.barCompleteString.substr(0, Math.round(params.progress*options.barsize));

    // end value reached ?
    // change color to green when finished
    if (params.value >= params.total){
        return '# ' + colors.grey(payload.task) + '   ' + colors.green(params.value + '/' + params.total) + ' --[' + bar + ']-- ';
    }else{
        return '# ' + payload.task + '   ' + colors.yellow(params.value + '/' + params.total) + ' --[' + bar + ']-- ';
    }
}

const opt = {
    format: formatter
}

is rendered as

# Task 1     0/200 --[]--
# Task 1     98/200 --[████████████████████]--
# Task 1     200/200 --[████████████████████████████████████████]--

Example 2

You can also access the default format functions to use them within your formatter:

const {TimeFormat, ValueFormat, BarFormat, Formatter} = require('cli-progess').Format;
...

Examples

Example 1 - Set Options

// change the progress characters
// set fps limit to 5
// change the output stream and barsize
const bar = new _progress.Bar({
    barCompleteChar: '#',
    barIncompleteChar: '.',
    fps: 5,
    stream: process.stdout,
    barsize: 65,
    position: 'center'
});

Example 2 - Change Styles defined by Preset

// uee shades preset
// change the barsize
const bar = new _progress.Bar({
    barsize: 65,
    position: 'right'
}, _progress.Presets.shades_grey);

Example 3 - Custom Payload

The payload object keys should only contain keys matching standard \w+ regex!

// create new progress bar with custom token "speed"
const bar = new _progress.Bar({
    format: 'progress [{bar}] {percentage}% | ETA: {eta}s | {value}/{total} | Speed: {speed} kbit'
});

// initialize the bar - set payload token "speed" with the default value "N/A"
bar.start(200, 0, {
    speed: "N/A"
});

// some code/update loop
// ...

// update bar value. set custom token "speed" to 125
bar.update(5, {
    speed: '125'
});

// process finished
bar.stop();

Example 4 - Custom Presets

File myPreset.js

const colors = require('ansi-colors');

module.exports = {
    format: colors.red(' {bar}') + ' {percentage}% | ETA: {eta}s | {value}/{total} | Speed: {speed} kbit',
    barCompleteChar: '\u2588',
    barIncompleteChar: '\u2591'
};

Application

const myPreset = require('./myPreset.js');

const bar = new _progress.Bar({
    barsize: 65
}, myPreset);

Presets/Themes

Need a more modern appearance ? cli-progress supports predefined themes via presets. You are welcome to add your custom one :)

But keep in mind that a lot of the "special-chars" rely on Unicode - it might not work as expected on legacy systems.

Default Presets

The following presets are included by default

• legacy - Styles as of cli-progress v1.3.0
• shades-classic - Unicode background shades are used for the bar
• shades-grey - Unicode background shades with grey bar
• rect - Unicode Rectangles

Compatibility

cli-progress is designed for linux/macOS/container applications which mostly providing standard compliant tty terminals/shells. In non-tty mode it is suitable to be used with logging daemons (cyclic output).

It also works with PowerShell on Windows 10 - the legacy command prompt on outdated Windows versions won't work as expected and is not supported!

Any Questions ? Report a Bug ? Enhancements ?

Please open a new issue on GitHub

License

CLI-Progress is OpenSource and licensed under the Terms of The MIT License (X11). You're welcome to contribute!