TypeError: Cannot read property 'then' of undefined

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1

My frontend page is calling a function which does a DB lookup and returns a boolean value based on it’s findings. But what’s happening is that the script is running past the lookup and I’m getting undefined errors.

backend\somefile.js(w) ++++ I tried both public and backend, neither work.

export function userSubCheck(em, sub) {
wixData.query(“Members”)
.eq(“email”, em) // em = email address
.find()
.then( (results) => {
let answer = false;
let check = results[“_items”][0][sub]; // sub = boolean
if (check) {
console.log(“Is Subscribed”);
answer = true;
}
return answer;
} )
.catch( (err) => {
console.log(err);
} );
}

=======================================================
Frontend code doing the calling, I get console errors on here…

import {userSubCheck} from ‘public/userSubCheck.js’; //or backend/, neither work.

let checkCat = session.getItem(“subCheck”);
let userEmail = session.getItem(“email”);

$w.onReady(function () {

userSubCheck(userEmail,checkCat).then(status => { 
	console.log(status); 
});

});

=======================================================
What I see in the console log is “undefined” from the frontend, THEN I get a “Is Subscribed” from the backend/public function. Why is this happening?

2

Hi PJ,

Please provide more details. What is “undefined”? What messages are you getting? What messages are you getting in the backend console log?

Yisrael

3

Hey PJ. I think the problem may be that you’re not returning the Promise from your query. You might want to take a look at this article: Velo: Working with Promises | Help Center | Wix.com

Especially, this section: Velo: Working with Promises | Help Center | Wix.com

4

Thank you Sam… That one word fixed my current issue! Thank you, great info on the docs too, much appreciated. :slight_smile: