private static string GetFirstItemLSN(Collection <JObject> items)
{
JObject item = RemainingWorkEstimatorCore.GetFirstItem(items);
if (item == null)
{
return(null);
}
if (item.TryGetValue(LSNPropertyName, StringComparison.OrdinalIgnoreCase, out JToken property))
{
return(property.Value <string>());
}
DefaultTrace.TraceWarning("Change Feed response item does not include LSN.");
return(null);
}
private async Task <long> GetRemainingWorkAsync(DocumentServiceLease existingLease, CancellationToken cancellationToken)
{
// Current lease schema maps Token to PKRangeId
string partitionKeyRangeId = existingLease.CurrentLeaseToken;
using FeedIterator iterator = this.feedCreator(
partitionKeyRangeId,
existingLease.ContinuationToken,
string.IsNullOrEmpty(existingLease.ContinuationToken));
try
{
ResponseMessage response = await iterator.ReadNextAsync(cancellationToken).ConfigureAwait(false);
if (response.StatusCode != HttpStatusCode.NotModified)
{
response.EnsureSuccessStatusCode();
}
long parsedLSNFromSessionToken = RemainingWorkEstimatorCore.TryConvertToNumber(ExtractLsnFromSessionToken(response.Headers[HttpConstants.HttpHeaders.SessionToken]));
IEnumerable <JObject> items = RemainingWorkEstimatorCore.GetItemsFromResponse(response);
long lastQueryLSN = items.Any()
? RemainingWorkEstimatorCore.TryConvertToNumber(RemainingWorkEstimatorCore.GetFirstItemLSN(items)) - 1
: parsedLSNFromSessionToken;
if (lastQueryLSN < 0)
{
return(1);
}
long leaseTokenRemainingWork = parsedLSNFromSessionToken - lastQueryLSN;
return(leaseTokenRemainingWork < 0 ? 0 : leaseTokenRemainingWork);
}
catch (Exception clientException)
{
Cosmos.Extensions.TraceException(clientException);
DefaultTrace.TraceWarning("GetEstimateWork > exception: lease token '{0}'", existingLease.CurrentLeaseToken);
throw;
}
}
