Why does my Parse Task sometimes not complete?

Question

I am calling a Parse cloud function which always works the first time, but subsequent calls only occasionally complete (meaning neither 'Error', 'Success', or 'Refresh Complete' is printed):

IEnumerator RefreshScores()
{
    Debug.Log("Asking Parse for scores...");

    var parameters = new Dictionary<string, object>();
    Task task = ParseCloud.CallFunctionAsync<IList<IDictionary<string, object>>>("getFriendsScores", parameters).ContinueWith(t =>
    {
        if (t.IsFaulted)
        {
            Debug.Log("Error!");
        }
        else
        {
            Debug.Log("Success!");
        }
    });

    while (!task.IsCompleted) yield return null;

    Debug.Log("Refresh Complete!");
}

I don't know why this is happening, but as an attempt to get around the inconsistency I tried passing a cancellation token to give up manually after x seconds, but that did not seem to have an effect either :(

Any help on the issue would be greatly appreciated.

Answer 1

As it turns out, the problem is unrelated to Parse, and rather caused by my misunderstanding of how Couroutines lifetimes are managed in Unity.

I was calling StartCouroutine(MySingleton.Instance.RefreshScores()); from an object that was disabled shortly afterwards, which in turn was ruining the co-routine.

The solution in my case was to create a public wrapper function on my singleton which then calls the co-routine from the correct object.