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I like the async await syntax, and I use it a lot with mongoose.

So in my project there is plenty of :

const user = await User.findOne({
    _id: req.params.id
Which works just as expected. However, in sonarqube, I have these errors :
Refactor this redundant 'await' on a non-promise.
And the sonarqube rule i :
  
It is possible to use await on values which are not Promises, but it's 
   useless and misleading. The point of await is to pause execution until 
   the Promise's asynchronous code has run to completion. With anything 
   other than a Promise, there's nothing to wait for.
  
This rule raises an issue when an awaited value is guaranteed not to be a Promise.
  
Noncompliant Code Example
let x = 42;
await x; // Noncompliant
  
Compliant Solution
let x = new Promise(resolve => resolve(42));
await x;
let y = p ? 42 : new Promise(resolve => resolve(42));
await y;
I am using mongo 4.0 and mongoose 5.3.1
Since I can use the .then, .catch syntax I thought that I was dealing with promise so how could I fix that ?
                The problem may be in how sonarqube is duck-typing the Query type.  From mongoose's own docs "Mongoose queries are not promises", however they are .then()able and are compliant with async/await so you may be getting a false positive.
– zero298
                Apr 30, 2019 at 18:53
                Not sure. But use .exec with the above query and see what happens.const user = await User.findOne({     _id: req.params.id }).exec()  Because mongoose queries are not full-fledged promises and .exec  help  to make it real promise.
– Ashh
                Apr 30, 2019 at 19:43
                @Fanpark by the way your solution fixed my issue so if you mind posting it as an answer I'll accept it
– L. Faros
                Jun 5, 2019 at 9:21
I do not know much about SonarQube. I just figured out SonarQube is tool to check the code quality and get that it required await only prefix with the promises and there mongoose fails even having .then.
Mongoose queries do not return "fully-fledged" promise even they have .then(). So in order to get "fully-fledged" promise you need to use .exec() function.
const user = await User.findOne({ _id: req.params.id }).exec()
As mentioned in the comments its a false positive, more accurately a depricated warning.
You can either ignore it or add this to your code right after the import statement:
mongoose.Promise = Promise; 
        
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