/// <summary>
/// Gets <see cref="PartitionKeyRange"/> instance which corresponds to <paramref name="rangeFromContinuationToken"/>
/// </summary>
/// <param name="providedPartitionKeyRanges"></param>
/// <param name="routingMapProvider"></param>
/// <param name="collectionRid"></param>
/// <param name="rangeFromContinuationToken"></param>
/// <param name="suppliedTokens"></param>
/// <param name="direction"></param>
/// <returns>null if collection with specified <paramref name="collectionRid"/> doesn't exist, which potentially means
/// that collection was resolved to outdated Rid by name. Also null can be returned if <paramref name="rangeFromContinuationToken"/>
/// is not found - this means it was split.
/// </returns>
public virtual async Task <ResolvedRangeInfo> TryGetTargetRangeFromContinuationTokenRangeAsync(
IReadOnlyList <Range <string> > providedPartitionKeyRanges,
IRoutingMapProvider routingMapProvider,
string collectionRid,
Range <string> rangeFromContinuationToken,
List <CompositeContinuationToken> suppliedTokens,
RntdbEnumerationDirection direction = RntdbEnumerationDirection.Forward)
{
// For queries such as "SELECT * FROM root WHERE false",
// we will have empty ranges and just forward the request to the first partition
if (providedPartitionKeyRanges.Count == 0)
{
return(new ResolvedRangeInfo(
await routingMapProvider.TryGetRangeByEffectivePartitionKeyAsync(
collectionRid,
PartitionKeyInternal.MinimumInclusiveEffectivePartitionKey),
suppliedTokens));
}
// Initially currentRange will be empty
if (rangeFromContinuationToken.IsEmpty)
{
if (direction == RntdbEnumerationDirection.Reverse)
{
PartitionKeyRange lastPartitionKeyRange = (await routingMapProvider.TryGetOverlappingRangesAsync(collectionRid, providedPartitionKeyRanges.Single())).Last();
return(new ResolvedRangeInfo(
lastPartitionKeyRange,
suppliedTokens));
}
Range <string> minimumRange = PartitionRoutingHelper.Min(
providedPartitionKeyRanges,
Range <string> .MinComparer.Instance);
return(new ResolvedRangeInfo(
await routingMapProvider.TryGetRangeByEffectivePartitionKeyAsync(collectionRid, minimumRange.Min),
suppliedTokens));
}
PartitionKeyRange targetPartitionKeyRange = await routingMapProvider.TryGetRangeByEffectivePartitionKeyAsync(collectionRid, rangeFromContinuationToken.Min);
if (targetPartitionKeyRange == null)
{
return(new ResolvedRangeInfo(null, suppliedTokens));
}
if (!rangeFromContinuationToken.Equals(targetPartitionKeyRange.ToRange()))
{
// Cannot find target range. Either collection was resolved incorrectly or the range was split
List <PartitionKeyRange> replacedRanges = (await routingMapProvider.TryGetOverlappingRangesAsync(collectionRid, rangeFromContinuationToken, true)).ToList();
if (replacedRanges == null || replacedRanges.Count < 1)
{
return(new ResolvedRangeInfo(null, null));
}
else
{
if (!(replacedRanges[0].MinInclusive.Equals(rangeFromContinuationToken.Min) && replacedRanges[replacedRanges.Count - 1].MaxExclusive.Equals(rangeFromContinuationToken.Max)))
{
return(new ResolvedRangeInfo(null, null));
}
}
if (direction == RntdbEnumerationDirection.Reverse)
{
replacedRanges.Reverse();
}
List <CompositeContinuationToken> continuationTokensToBePersisted = null;
if (suppliedTokens != null && suppliedTokens.Count > 0)
{
continuationTokensToBePersisted = new List <CompositeContinuationToken>(replacedRanges.Count + suppliedTokens.Count - 1);
foreach (PartitionKeyRange partitionKeyRange in replacedRanges)
{
CompositeContinuationToken token = (CompositeContinuationToken)suppliedTokens[0].ShallowCopy();
token.Range = partitionKeyRange.ToRange();
continuationTokensToBePersisted.Add(token);
}
continuationTokensToBePersisted.AddRange(suppliedTokens.Skip(1));
}
return(new ResolvedRangeInfo(replacedRanges[0], continuationTokensToBePersisted));
}
return(new ResolvedRangeInfo(targetPartitionKeyRange, suppliedTokens));
}
public virtual async Task <bool> TryAddPartitionKeyRangeToContinuationTokenAsync(
INameValueCollection backendResponseHeaders,
IReadOnlyList <Range <string> > providedPartitionKeyRanges,
IRoutingMapProvider routingMapProvider,
string collectionRid,
ResolvedRangeInfo resolvedRangeInfo,
RntdbEnumerationDirection direction = RntdbEnumerationDirection.Forward)
{
Debug.Assert(resolvedRangeInfo.ResolvedRange != null, "ResolvedRange can't be null");
PartitionKeyRange currentRange = resolvedRangeInfo.ResolvedRange;
// IF : Split happened, or already had multiple target ranges in the continuation
if (resolvedRangeInfo.ContinuationTokens != null && resolvedRangeInfo.ContinuationTokens.Count > 1)
{
if (!string.IsNullOrEmpty(backendResponseHeaders[HttpConstants.HttpHeaders.Continuation]))
{
resolvedRangeInfo.ContinuationTokens[0].Token = backendResponseHeaders[HttpConstants.HttpHeaders.Continuation];
}
else
{
resolvedRangeInfo.ContinuationTokens.RemoveAt(0);
}
backendResponseHeaders[HttpConstants.HttpHeaders.Continuation] = JsonConvert.SerializeObject(resolvedRangeInfo.ContinuationTokens);
}
else
{
//// ELSE: Single target Range was provided, and no split happened
PartitionKeyRange rangeToUse = currentRange;
// We only need to get the next range if we have to
if (string.IsNullOrEmpty(backendResponseHeaders[HttpConstants.HttpHeaders.Continuation]))
{
if (direction == RntdbEnumerationDirection.Reverse)
{
rangeToUse = PartitionRoutingHelper.MinBefore(
(await routingMapProvider.TryGetOverlappingRangesAsync(collectionRid, providedPartitionKeyRanges.Single())).ToList(),
currentRange);
}
else
{
Range <string> nextProvidedRange = PartitionRoutingHelper.MinAfter(
providedPartitionKeyRanges,
currentRange.ToRange(),
Range <string> .MaxComparer.Instance);
if (nextProvidedRange == null)
{
return(true);
}
string max = string.CompareOrdinal(nextProvidedRange.Min, currentRange.MaxExclusive) > 0
? nextProvidedRange.Min
: currentRange.MaxExclusive;
if (string.CompareOrdinal(max, PartitionKeyInternal.MaximumExclusiveEffectivePartitionKey) == 0)
{
return(true);
}
PartitionKeyRange nextRange = await routingMapProvider.TryGetRangeByEffectivePartitionKeyAsync(collectionRid, max);
if (nextRange == null)
{
return(false);
}
rangeToUse = nextRange;
}
}
if (rangeToUse != null)
{
backendResponseHeaders[HttpConstants.HttpHeaders.Continuation] = PartitionRoutingHelper.AddPartitionKeyRangeToContinuationToken(
backendResponseHeaders[HttpConstants.HttpHeaders.Continuation],
rangeToUse);
}
}
return(true);
}
public override async Task <ResponseMessage> SendAsync(
RequestMessage request,
CancellationToken cancellationToken)
{
using (ITrace childTrace = request.Trace.StartChild(this.FullHandlerName, TraceComponent.RequestHandler, Tracing.TraceLevel.Info))
{
request.Trace = childTrace;
ResponseMessage response = null;
string originalContinuation = request.Headers.ContinuationToken;
try
{
RntdbEnumerationDirection rntdbEnumerationDirection = RntdbEnumerationDirection.Forward;
if (request.Properties.TryGetValue(HttpConstants.HttpHeaders.EnumerationDirection, out object direction))
{
rntdbEnumerationDirection = (byte)direction == (byte)RntdbEnumerationDirection.Reverse ? RntdbEnumerationDirection.Reverse : RntdbEnumerationDirection.Forward;
}
request.Headers.Remove(HttpConstants.HttpHeaders.IsContinuationExpected);
request.Headers.Add(HttpConstants.HttpHeaders.IsContinuationExpected, bool.TrueString);
if (!request.Properties.TryGetValue(HandlerConstants.StartEpkString, out object startEpk))
{
startEpk = PartitionKeyInternal.MinimumInclusiveEffectivePartitionKey;
}
if (!request.Properties.TryGetValue(HandlerConstants.EndEpkString, out object endEpk))
{
endEpk = PartitionKeyInternal.MaximumExclusiveEffectivePartitionKey;
}
startEpk ??= PartitionKeyInternal.MinimumInclusiveEffectivePartitionKey;
endEpk ??= PartitionKeyInternal.MaximumExclusiveEffectivePartitionKey;
List <Range <string> > providedRanges = new List <Range <string> >
{
new Range <string>(
(string)startEpk,
(string)endEpk,
isMinInclusive: true,
isMaxInclusive: false)
};
DocumentServiceRequest serviceRequest = request.ToDocumentServiceRequest();
PartitionKeyRangeCache routingMapProvider = await this.client.DocumentClient.GetPartitionKeyRangeCacheAsync();
CollectionCache collectionCache = await this.client.DocumentClient.GetCollectionCacheAsync(NoOpTrace.Singleton);
ContainerProperties collectionFromCache =
await collectionCache.ResolveCollectionAsync(serviceRequest, CancellationToken.None);
//direction is not expected to change between continuations.
Range <string> rangeFromContinuationToken =
this.partitionRoutingHelper.ExtractPartitionKeyRangeFromContinuationToken(serviceRequest.Headers, out List <CompositeContinuationToken> suppliedTokens);
ResolvedRangeInfo resolvedRangeInfo =
await this.partitionRoutingHelper.TryGetTargetRangeFromContinuationTokenRangeAsync(
providedPartitionKeyRanges : providedRanges,
routingMapProvider : routingMapProvider,
collectionRid : collectionFromCache.ResourceId,
rangeFromContinuationToken : rangeFromContinuationToken,
suppliedTokens : suppliedTokens,
direction : rntdbEnumerationDirection);
if (serviceRequest.IsNameBased && resolvedRangeInfo.ResolvedRange == null && resolvedRangeInfo.ContinuationTokens == null)
{
serviceRequest.ForceNameCacheRefresh = true;
collectionFromCache = await collectionCache.ResolveCollectionAsync(serviceRequest, CancellationToken.None);
resolvedRangeInfo = await this.partitionRoutingHelper.TryGetTargetRangeFromContinuationTokenRangeAsync(
providedPartitionKeyRanges : providedRanges,
routingMapProvider : routingMapProvider,
collectionRid : collectionFromCache.ResourceId,
rangeFromContinuationToken : rangeFromContinuationToken,
suppliedTokens : suppliedTokens,
direction : rntdbEnumerationDirection);
}
if (resolvedRangeInfo.ResolvedRange == null && resolvedRangeInfo.ContinuationTokens == null)
{
return(((DocumentClientException) new NotFoundException(
$"{DateTime.UtcNow.ToString("o", CultureInfo.InvariantCulture)}: Was not able to get queryRoutingInfo even after resolve collection async with force name cache refresh to the following collectionRid: {collectionFromCache.ResourceId} with the supplied tokens: {JsonConvert.SerializeObject(suppliedTokens)}")
).ToCosmosResponseMessage(request));
}
serviceRequest.RouteTo(new PartitionKeyRangeIdentity(collectionFromCache.ResourceId, resolvedRangeInfo.ResolvedRange.Id));
response = await base.SendAsync(request, cancellationToken);
if (!response.IsSuccessStatusCode)
{
this.SetOriginalContinuationToken(request, response, originalContinuation);
}
else
{
if (!await this.partitionRoutingHelper.TryAddPartitionKeyRangeToContinuationTokenAsync(
response.Headers.CosmosMessageHeaders,
providedPartitionKeyRanges: providedRanges,
routingMapProvider: routingMapProvider,
collectionRid: collectionFromCache.ResourceId,
resolvedRangeInfo: resolvedRangeInfo,
direction: rntdbEnumerationDirection))
{
return(((DocumentClientException) new NotFoundException(
$"{DateTime.UtcNow.ToString("o", CultureInfo.InvariantCulture)}: Call to TryAddPartitionKeyRangeToContinuationTokenAsync failed to the following collectionRid: {collectionFromCache.ResourceId} with the supplied tokens: {JsonConvert.SerializeObject(suppliedTokens)}")
).ToCosmosResponseMessage(request));
}
}
return(response);
}
catch (DocumentClientException ex)
{
ResponseMessage errorResponse = ex.ToCosmosResponseMessage(request);
this.SetOriginalContinuationToken(request, errorResponse, originalContinuation);
return(errorResponse);
}
catch (CosmosException ex)
{
ResponseMessage errorResponse = ex.ToCosmosResponseMessage(request);
this.SetOriginalContinuationToken(request, errorResponse, originalContinuation);
return(errorResponse);
}
catch (AggregateException ex)
{
this.SetOriginalContinuationToken(request, response, originalContinuation);
// TODO: because the SDK underneath this path uses ContinueWith or task.Result we need to catch AggregateExceptions here
// in order to ensure that underlying DocumentClientExceptions get propagated up correctly. Once all ContinueWith and .Result
// is removed this catch can be safely removed.
AggregateException innerExceptions = ex.Flatten();
Exception docClientException = innerExceptions.InnerExceptions.FirstOrDefault(innerEx => innerEx is DocumentClientException);
if (docClientException != null)
{
return(((DocumentClientException)docClientException).ToCosmosResponseMessage(request));
}
throw;
}
}
}
