Is my sqlite request inside my async function also asynchronous? - node.js

Question

I'm using node.js and npm's sqlite package and discord.js to make a discord bot.
I try to get a array back from a async function containing a sqlite request.
It seems like my sqlite request is also asynchronous cause I get the empty response before the request is executed. How do I have to form my request to get it executed first?
I already read this post: How do I return the response from an asynchronous call? but I still dont get it. It is not a duplicate cause the question in the link is about ajax and did not help me much. I hope that if I see it with my own code I'm able to understand it better.
This is what I'm having at the moment. I already tried it with callbacks without a result.
Promise approach:
This is my async function in dbHandler.js.
var Promise = require("bluebird");
getList: function(userID) {
return new Promise(function(resolve, reject) {
var array = [];
sql.each(`SELECT * FROM table WHERE userID = ?`, userID, (err, row) => {
if (err) {
return console.error(err);
} else {
console.log("row: " + row + " element: " + row.username);
array.push(row);
}
});
array.forEach(function(element) {
console.log("element: " + element.username);
});
console.log("array: " + array);
resolve(array);
});
}
And this is my call in list.js.
db.getList(uid)
.then(function(v) {
console.log("size: " + v.size);
})
.catch(function(v) {
console.log("failed: " + v);
});
In console I get this.
array:
size: undefined
row: [object Object] element: user1
row: [object Object] element: user2
row: [object Object] element: user3
Callback approach:
dbHandler.js
getList: function(userID, callback) {
var array = [];
sql.each(`SELECT * FROM warns WHERE userID = ?`, userID, (err, row) => {
if (err) {
return console.error(err);
} else {
array.push(row);
}
});
if (array) {
callback("", array);
} else {
callback("error", "");
}
},
list.js
db.getList(uid, function (err, response) {
if (err) {
console.log(err);
} else {
console.log(response.size);
}
});
With the callback approach I only get undefined in console.

Answer 1

since you get the following output:
row: [object Object] element: user1
row: [object Object] element: user2
row: [object Object] element: user3
I can only assume that you get results from the database, but accessing it is the issue. I'd suggest you try to dump the whole object and see it's structure before deciding on how to access it.
Below I have modified your code to dump a readable version of the object. Start from there and debug.
getList: function(userID) {
return new Promise(function(resolve, reject) {
var array = [];
sql.each(`SELECT * FROM table WHERE userID = ?`, userID, (err, row) => {
if (err) {
return console.error(err);
} else {
console.log(JSON.stringify(row)); //lets get the contents of the row object
array.push(row); console.log(JSON.stringify(array)); //also, lets know what array contains after adding all the rows
}
});