nurl/public/javascripts/shorten.js

function shorten(){
    $.ajax({
        url: '/api/v1/shorten',
        type: 'POST',
        dataType: 'JSON',
        data: {url: $('#url-field').val()},
        success: function(data){
            console.log('data', data);
            const $link = $('#link');
            const resultHTML = `<a class="result" href="${data.shortUrl}">${data.shortUrl}</a>`;
            $link.html(resultHTML);
            $link.hide().fadeIn('slow');

        }
      });
}

$("#url-field").keyup(function(event){
    if(event.keyCode === 13){
        $("#btn-shorten").click();
    }
});

$('#btn-shorten').on('click', function(){
    shorten();
});