public async Task <ICourse> GetCourseById(Guid id)
{
if (id == Guid.Empty)
{
throw new ArgumentException($"Cannot be an empty {nameof(Guid)}", nameof(id));
}
Course persisted = null;
using (var client = _cosmosDbHelper.GetClient())
{
var doc = await _cosmosDbHelper.GetDocumentByIdAsync(client, _settings.CoursesCollectionId, id);
persisted = _cosmosDbHelper.DocumentTo <Course>(doc);
}
return(persisted);
}