/// <summary>
/// Get the next set of results from the cosmos service
/// </summary>
/// <param name="cancellationToken">(Optional) <see cref="CancellationToken"/> representing request cancellation.</param>
/// <returns>A query response from cosmos service</returns>
public override Task <ResponseMessage> ReadNextAsync(CancellationToken cancellationToken = default)
{
CosmosDiagnosticsContext diagnostics = CosmosDiagnosticsContext.Create(this.requestOptions);
using (diagnostics.CreateOverallScope("FeedReadNextAsync"))
{
return(this.ReadNextInternalAsync(diagnostics, cancellationToken));
}
}
// Extracted partition key might be invalid as CollectionCache might be stale.
// Stale collection cache is refreshed through PartitionKeyMismatchRetryPolicy
// and partition-key is extracted again.
internal async Task <ResponseMessage> ExtractPartitionKeyAndProcessItemStreamAsync <T>(
PartitionKey?partitionKey,
string itemId,
T item,
OperationType operationType,
RequestOptions requestOptions,
CancellationToken cancellationToken)
{
CosmosDiagnosticsContext diagnosticsContext = CosmosDiagnosticsContext.Create(requestOptions);
using (diagnosticsContext.CreateOverallScope("ItemStream"))
{
Stream itemStream;
using (diagnosticsContext.CreateScope("ItemSerialize"))
{
itemStream = this.ClientContext.SerializerCore.ToStream <T>(item);
}
// User specified PK value, no need to extract it
if (partitionKey.HasValue)
{
return(await this.ProcessItemStreamAsync(
partitionKey,
itemId,
itemStream,
operationType,
requestOptions,
diagnosticsScope : diagnosticsContext,
cancellationToken : cancellationToken));
}
PartitionKeyMismatchRetryPolicy requestRetryPolicy = null;
while (true)
{
using (diagnosticsContext.CreateScope("ExtractPkValue"))
{
partitionKey = await this.GetPartitionKeyValueFromStreamAsync(itemStream, cancellationToken);
}
ResponseMessage responseMessage = await this.ProcessItemStreamAsync(
partitionKey,
itemId,
itemStream,
operationType,
requestOptions,
diagnosticsScope : diagnosticsContext,
cancellationToken : cancellationToken);
if (responseMessage.IsSuccessStatusCode)
{
return(responseMessage);
}
if (requestRetryPolicy == null)
{
requestRetryPolicy = new PartitionKeyMismatchRetryPolicy(await this.ClientContext.DocumentClient.GetCollectionCacheAsync(), null);
}
ShouldRetryResult retryResult = await requestRetryPolicy.ShouldRetryAsync(responseMessage, cancellationToken);
if (!retryResult.ShouldRetry)
{
return(responseMessage);
}
}
}
}
internal async Task <ResponseMessage> ProcessItemStreamAsync(
PartitionKey?partitionKey,
string itemId,
Stream streamPayload,
OperationType operationType,
ItemRequestOptions requestOptions,
CosmosDiagnosticsContext diagnosticsContext,
CancellationToken cancellationToken)
{
if (requestOptions != null && requestOptions.IsEffectivePartitionKeyRouting)
{
partitionKey = null;
}
ContainerCore.ValidatePartitionKey(partitionKey, requestOptions);
Uri resourceUri = this.GetResourceUri(requestOptions, operationType, itemId);
if (diagnosticsContext == null)
{
diagnosticsContext = CosmosDiagnosticsContext.Create(requestOptions);
}
using (diagnosticsContext.CreateOverallScope("ProcessItemStream"))
{
if (requestOptions != null && requestOptions.EncryptionOptions != null)
{
if (streamPayload == null)
{
throw new ArgumentException(ClientResources.InvalidRequestWithEncryptionOptions);
}
using (diagnosticsContext.CreateScope("Encrypt"))
{
streamPayload = await this.ClientContext.EncryptionProcessor.EncryptAsync(
streamPayload,
requestOptions.EncryptionOptions,
(DatabaseCore)this.Database,
this.ClientContext.ClientOptions.EncryptionKeyWrapProvider,
diagnosticsContext,
cancellationToken);
}
}
ResponseMessage responseMessage = await this.ClientContext.ProcessResourceOperationStreamAsync(
resourceUri : resourceUri,
resourceType : ResourceType.Document,
operationType : operationType,
requestOptions : requestOptions,
cosmosContainerCore : this,
partitionKey : partitionKey,
itemId : itemId,
streamPayload : streamPayload,
requestEnricher : null,
diagnosticsScope : diagnosticsContext,
cancellationToken : cancellationToken);
if (responseMessage.Content != null && this.ClientContext.ClientOptions.EncryptionKeyWrapProvider != null)
{
using (diagnosticsContext.CreateScope("Decrypt"))
{
responseMessage.Content = await this.ClientContext.EncryptionProcessor.DecryptAsync(
responseMessage.Content,
(DatabaseCore)this.Database,
this.ClientContext.ClientOptions.EncryptionKeyWrapProvider,
diagnosticsContext,
cancellationToken);
}
}
return(responseMessage);
}
}