private async Task <DocumentCollection> GetOrCreateCollectionAsync(string databaseId, string collectionId) { var databaseUri = UriFactory.CreateDatabaseUri(databaseId); var collection = Client.CreateDocumentCollectionQuery(databaseUri) .Where(c => c.Id == collectionId) .AsEnumerable() .FirstOrDefault() ?? await Client.CreateDocumentCollectionAsync(databaseUri, new DocumentCollection { Id = collectionId }); return(collection); }