private async Task <CosmosClientQueryResult <Activity> > FetchPageOfActivities(Expression <Func <Activity, bool> > selection, string continuationToken)
{
var collectionUri = GetCollectionUri(CollectionName);
var options = new FeedOptions
{
MaxItemCount = 1000,
RequestContinuation = continuationToken
};
var query = _client.Value
.CreateDocumentQuery <Activity>(collectionUri, options)
.Where(selection)
.OrderBy(activity => activity.At)
.AsDocumentQuery();
Stopwatch sw = new Stopwatch();
sw.Start();
var page = await query.ExecuteNextAsync <Activity>();
sw.Stop();
var pageResult = new CosmosClientQueryResult <Activity>(
query.HasMoreResults ? page.ResponseContinuation : null,
page.ToArray())
{
Cost = new OperationCost(query.ToString(), page.RequestCharge, sw.ElapsedTicks)
};
return(pageResult);
}
private async Task FetchAllMatchingActivities(Expression <Func <Activity, bool> > selection, GroupOperationCost groupOperationCost)
{
CosmosClientQueryResult <Activity> page = null;
do
{
page = await FetchPageOfActivities(selection, page?.ContinuationToken);
groupOperationCost.StepCosts.Add(page.Cost);
}while (page.ContinuationToken != null);
}