function insertNewURL() {
    var url = document.getElementById ( "form-url" ).value;
    var xhr = new XMLHttpRequest ( );
    xhr.open ( "POST", 'insert', true );
    xhr.onreadystatechange = function ( ) {
        if ( xhr.status == 200 ) {
            if ( xhr.readyState == XMLHttpRequest.DONE ) {
                var response = xhr.responseText;
                response = JSON.parse ( response );
                if ( response [ 'status' ] == 200 ) {
                    document.getElementById ( "responsetext" ).innerHTML = response [ 'message' ];
                    setTimeout( function( ) {
                        document.getElementById ( 'responsetext' ).innerHTML = ""
                    }, 1500 );
                    var div = document.createElement ( 'div' );
                    div.innerHTML = response [ 'last_insert' ] + " | " + url;
                    document.getElementById ( "urllist" ).appendChild ( div );
                    document.getElementById ( "form-url" ).value = "";
                }
                else {
                    document.getElementById ( "responsetext" ).innerHTML = response [ 'error_message' ];
                    setTimeout( function( ) {
                        document.getElementById ( 'responsetext' ).innerHTML = ""
                    }, 1500 );
                }
            }
            else {
                console.log ( 'Server communication error: ' + xhr.statusText );
            }
        }
        else {
            document.getElementById ( "responsetext" ).innerHTML = response [ 'error_message' ];
                setTimeout( function( ) {
                    document.getElementById ( 'responsetext' ).innerHTML = ""
                }, 1500 );
        }
    }
    data = new FormData ( );
    data.append('url', url);
    xhr.send( data );
}