replace-printer

This package is rather basic, if you need something more elaborate you could look into the ink package.

This package is meant to help you to construct continues in place output. For example this could be helpful to monitor the state of your application or to keep you updated on the current connections, cpu consumption or something else.

This package provides you with an easy to use way to print and then replace the printed with something else.

usage

To use the package you can use the ReplacePrinter class.

const {ReplacePrinter} = require('replace-printer');

const {continuesConsole, replaceConsole} = new ReplacePrinter();

// if you want to print something the ordinary way in the meantime you can just do so by using
continuesConsole.log('This is some event like print, which will scroll like always.', {withSome: 'object'});

const timespan = 6000;
const startTime = Date.now();

setTimeout(() => {
    continuesConsole.log('This is some event like print, which will scroll like always which appears after about %dms', Date.now() - startTime);
}, timespan / 2);

const intervalId = setInterval(() => {
    const remainingTime = timespan - Date.now() + startTime;
    replaceConsole.log('This is some replaceable Text\n\twhich will be replaced in %dms', remainingTime);

    if (remainingTime <= 0) {
        clearInterval(intervalId);
        replaceConsole.log('Whoosh and the text was removed.');
    }
}, 16);

You can find this in examples\test-01.js

const {ReplacePrinter} = require('replace-printer');

const {continuesConsole, replaceConsole} = new ReplacePrinter();

replaceConsole.log('This is my object:', {field: 'test'});

setTimeout(() => {
    // if you want to print something the ordinary way in the meantime you can just do so by using
    continuesConsole.log('This is some event like print, which will scroll like always.', {withSome: 'object'});
}, 2000);

setTimeout(() => {
    replaceConsole.log('Whoosh and the message was removed.');
}, 5000);

You can find this in examples\test-02.js

If you want to use multiple ReplacePrinter or if you want to resume the usage of other logging utilities you need to call endWithNewLine. Otherwise you will append the same line as the last replace message was printed.

const {ReplacePrinter} = require('replace-printer');

const waitMs = ms => new Promise(res => setTimeout(res, ms));
const doEveryTill = (every, till, action) => {
    const endTs = Date.now() + till;
    return new Promise(res => {
        const intervalTo = setInterval(() => {
            const isLAst = Date.now() > endTs;
            action(isLAst);

            if (isLAst) {
                clearInterval(intervalTo);
                res();
            }
        }, every);
    });
}

(async () => {
    const rp1 = new ReplacePrinter();
    const rc1 = rp1.replaceConsole;

    rc1.log('This is a log of\na new line which is long');
    await waitMs(2500);
    rc1.log('This is another line\nwhich is broken into two');
    await waitMs(2000);

    // Warning: Never mix two ReplacePrinter, this will result in unexpected behavior!
    // You should call endWithNewLine when you are done printing with the ReplacePrinter and want to print something else
    rp1.endWithNewLine();

    const rp2 = new ReplacePrinter();
    const rc2 = rp2.replaceConsole;
    const cc2 = rp2.continuesConsole;

    let framesPrinted = 0;
    await doEveryTill(5, 4000, (isLast) => {
        framesPrinted++;
        const frameString = '[' + framesPrinted.toString().padStart(4, '0') + ']';
        if (isLast)
            rc2.log(frameString + ' This is the last log')
        else
            rc2.log(frameString + ' Another line which is meant\nto be broken up into multiple ' + Date());
    })

    cc2.log('framesPrinted', framesPrinted);
})().catch(err => {
    console.error(err);
    process.exit(1)
})

You can find this in examples\test-03.js