Search code examples
node.jsunicodecommand-line

How to show progress icons in terminal programs like seen here?

I want to write a command-line program that will show UNICODE characters that will "animate" in the left side of a line. How can I do it using node.js to have the checkmark and UNICODE animation you see here in the following image? What are the characters, and how do I make the instructions to overwrite the first character on the line?

Example of the icons

Solution

  • You can build your own spinner in node by writing to stdout like this:

    import { stdout } from "process"

function startSpinner() {
    const characters = ['⠋', '⠙', '⠹', '⠸', '⠼', '⠴', '⠦', '⠧', '⠇', '⠏']
    const cursorEsc = {
        hide: '\u001B[?25l',
        show: '\u001B[?25h',
    }
    stdout.write(cursorEsc.hide)

    let i = 0;
    const timer = setInterval(function () {
        stdout.write("\r" + characters[i++]);
        i = i >= characters.length ? 0 : i;
    }, 150);

    return () => {
        clearInterval(timer)
        stdout.write("\r")
        stdout.write(cursorEsc.show)
    }
}

    Then invoke the function like this - here's an example that runs for 4 seconds and then finishes

    const stopSpinner = startSpinner();

setTimeout(() => {
    stopSpinner()
    console.log("done")
},4000)

    Further Reading