I'm trying to create a simple web page to display the contents of a table stored in a sqlite3 table. I'm using vanilla js for the frontend (NO JQUERY!) and node.js + sqlite3 for the backend. I can query the database just fine within my node script but can't figure out how to return the results to my frontend js script. The problem seems to be that since the queries are asynchronous, the function ( get_rows() ) returns before the queries are complete. Code below.

main.js (frontend script used by web page)

    xmlhttp.open("POST", "http://localhost:3000/load", true);
    xmlhttp.onreadystatechange = function() {
        if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
            console.log(xmlhttp.responseText);
            let rows = JSON.parse(xmlhttp.responseText);
            console.log(rows);
            //now we can parse rows and create table
            console.log("rows: " + rows);
        }
    }
    xmlhttp.setRequestHeader("Content-Type", "text/plain", "Access-Control-Allow-Origin", "*");
    xmlhttp.send(tbl_name); 

access.js (node.js script handling sqlite3 query)

const http = require('http');
const url = require('url');
const sqlite = require('sqlite3').verbose();


 get_rows = function(table) {
    let test = null;

    //open database
    let db = new sqlite.Database("../../databases/test_db.db", err=> {
        if (err) {
            console.error(err.message);
        }
        console.log("Opened database from disk");
    });

    //get rows
    db.all('SELECT * FROM ' + table, (err, row) => {
        if (err) {
            console.error(err.essage);
        }
        test = row;
    });
    //close database
    db.close((err) => {
        if (err) {
            console.error(err.message);
        }
        console.log("Closed database");
    });

    return test;
}

http.createServer(function (req, res) {
    let path = url.parse(req.url).pathname;
    res.writeHead(200, {"Content-type": "text/plain", 'Access-Control-Allow-Origin' : '*'});

    if (path === "/load") {
        req.on("data", function(tbl_name) {
            console.log("Loaded table: " + tbl_name);
            res.end(get_rows(tbl_name));
       });
    }
}).listen(3000);