Log by overwriting the previous output in the terminal. Useful for rendering progress bars, animations, etc.


Keywords
log, logger, logging, cli, terminal, term, console, shell, update, refresh, overwrite, output, stdout, progress, bar, animation
License
MIT
Install
npm install log-update@4.0.0

Documentation

log-update

Log by overwriting the previous output in the terminal.
Useful for rendering progress bars, animations, etc.

Install

npm install log-update

Usage

import logUpdate from 'log-update';

const frames = ['-', '\\', '|', '/'];
let index = 0;

setInterval(() => {
	const frame = frames[index = ++index % frames.length];

	logUpdate(
`
        ♥♥
   ${frame} unicorns ${frame}
        ♥♥
`
	);
}, 80);

API

logUpdate(text…)

Log to stdout.

logUpdate.clear()

Clear the logged output.

logUpdate.done()

Persist the logged output.

Useful if you want to start a new log session below the current one.

logUpdateStderr(text…)

Log to stderr.

logUpdateStderr.clear()

logUpdateStderr.done()

createLogUpdate(stream, options?)

Get a logUpdate method that logs to the specified stream.

options

Type: object

showCursor

Type: boolean
Default: false

Show the cursor. This can be useful when a CLI accepts input from a user.

import {createLogUpdate} from 'log-update';

// Write output but don't hide the cursor
const log = createLogUpdate(process.stdout, {
	showCursor: true
});

Examples

  • listr - Uses this module to render an interactive task list
  • ora - Uses this module to render awesome spinners
  • speed-test - Uses this module to render a spinner