I have spent tow day to solve this problem but got nothing. All the answers in stackoverflow didn't work for me.
here is my code
const userCredential = require("./db").db().collection("api");
now I want to retrieve a doc like API to save it on a variable
const api = userCredential.findOne({username:'admin'}, (err, doc)=> (doc.username))
and now I want to use the variable to anywhere in the file. But it returned undefined.
if I try this one
let api;
userCredential.findOne({username:'admin'}, (err, doc)=> (api = doc.api))
also return undefined because of nature of Asynchronous.
How can I save in to a variable?
Please try below code
function query(username) {
console.log('query');
Test.findOne({ username: username }, function (err, result) {
console.log('findOne callback');
if (err) {
return console.error(err);
} else {
console.log(`result: ${result}`);
return ${result};
}
});
}
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