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Hey guys, I have 3 methods inside a `ViewModel` in the image below, calling methods on some repository.
All methods attempt to do the same thing:

*Fetch a value from the local DB (a Room DB), suspend the method execution until that value is fetched so the method is guaranteed to return a value.*

In each method I added a comment that specifies what issue I have with this method.

What is the safe and correct way to accomplish what I am trying to do?
Slack Conversation

`launch` is a fire-and-forget construct which exits immediately after you invoke it, so it’s not guaranteed that your `viewModelScope.launch` will run or complete before your function returns in `getCityByID`. What you probably want to do there is turn `getCityByID` into a `suspend fun` and just do something to the effect of:

```val city = withContext(viewModelScope) {
    locationRepository.getSingleCityFromDatabaseByID(selectedCityID)
}
return city```
if you need to run that inside the viewModelScope and not the caller’s scope. If you’d rather run in the caller’s scope you can simply do:
```return locationRepository.getSingleCityFromDatabaseByID(selectedCityID)```
as long as you make it a `suspend fun`.

Same concept applies across your other two functions as well.

If you’re okay with blocking a thread you can also use `runBlocking(viewModelScope) { …`

That way you wouldn’t need to make it a suspend fun

I’d recommend making it a suspend fun though

Thanks <@UK6EAK2PJ>! your solution is way much cleaner than what I used by far (I used LiveData and observables)

Yup, coroutines should just look like blocking code :slightly_smiling_face:

<@UK6EAK2PJ>

I can’t call the above code:
```suspend fun test(selectedCityId: Int, selectedLanguages: List&lt;Int&gt;, selectedExpertiseFieldId: Int){
    val city = withContext(viewModelScope){
        locationRepository.getSingleCityFromDatabaseByID(selectedCityID)
    }
    return city
}```


how about just using `async` instead of launch:

```suspend fun getCityById(selectedCityId: Int): City =
    viewModelScope.async {
        locationRepository.getSingleCityFromDatabaseByID(selectedCityID)
    }.await()```

<@UST13JB4P>
Seems cleaner, but where did I called `launch`?
I assume I implicitly did that when calling `withContext` am I correct?

You used `launch` in your initial example; I am not exactly sure about implementation details of `withContext` , sadly.