How to rewrite a php script to JavaScript - php

Question

I have an express server running using nodejs, and I'm using SQL syntax to query data from my MYSQL database.
The query is to get all members under the current user ID and also get members under it's children and so on, to get a genealogy tree. I'm trying to query a genealogy tree for a user.
I have a PHP script for the query, which worked fine
This is the PHP script:
$memory = $_GET['memory'];
echo '<div style="background:#ccc;display:flex;width:50px;height:50px;justify-
content:center;align-items:center;border-radius:50%;">'.$memory.'</div>';
$transend = array($memory);
$step = 1;
for ($i=0; $i < $step; $i++) {
$under = $transend[$i];
$get = $con->query("SELECT * FROM multilevel WHERE `under`='$under'");
$cnt = $get->num_rows;
if ($cnt>0) {
for ($g=0; $g < $cnt; $g++) {
$fet = $get->fetch_object();
$id = $fet->id;
$position = $fet->position;
array_push($transend, $id);
$step = $step*2;
echo '<div style="background:#ccc;display:flex;width:50px;height:50px;justify-content:center;align-items:center;border-radius:50%;">'.$id.'-'.$position.'</div>';
}
} else {
break;
}
}
I am trying to rewrite it using SQL syntax in node. This is my nodejs code:
A Tree Constructor
const Tree = function (binary) {
this.position = binary.position;
this.level = binary.level;
this.user_id = binary.user_id;
this.under_user_id = binary.under_user_id;
this.brought_by = binary.brought_by;
this.username = binary.username;
};
A method to get all binary for a user
Tree.findBinaries = async (id, result) => {
const theId = parseInt(id);
let transend = [theId];
let step = 1;
let data = [];
for (let i = 0; i < step; i++) {
const under = transend[i];
connection.query(
`SELECT * FROM multilevel WHERE under = ?`,
under,
(err, res) => {
if (err) {
result(null, err);
return;
}
if (res.length) {
for (let index = 0; index < res.length; index++) {
const { id } = res[index];
// push id
transend.push(id);
data.push(res[index]);
step = step * 2;
}
result(null, data);
} else {
result(null, "no data found");
}
}
);
}
};
The transend.push(id) and data.push(res[index]), are not been pushed to the top level, also the step is not been updated. So the loop is running just once.
The expected Result is supposed to be 16 items of children and children of children, But it is currently returning to just the first level. I don't know what I'm currently doing wrong.