public async Task StartFromTimeAsync(bool useContinuations)
{
int numItems = 100;
IDocumentContainer documentContainer = await CreateDocumentContainerAsync(numItems);
TryCatch <CrossPartitionChangeFeedAsyncEnumerator> monadicEnumerator = CrossPartitionChangeFeedAsyncEnumerator.MonadicCreate(
documentContainer,
new ChangeFeedRequestOptions(),
ChangeFeedStartFrom.Time(DateTime.UtcNow),
cancellationToken: default);
for (int i = 0; i < numItems; i++)
{
// Insert an item
CosmosObject item = CosmosObject.Parse($"{{\"pk\" : {i} }}");
while (true)
{
TryCatch <Record> monadicCreateRecord = await documentContainer.MonadicCreateItemAsync(item, cancellationToken : default);
if (monadicCreateRecord.Succeeded)
{
break;
}
}
}
Assert.IsTrue(monadicEnumerator.Succeeded);
CrossPartitionChangeFeedAsyncEnumerator enumerator = monadicEnumerator.Result;
int globalCount = await(useContinuations
? DrainWithUntilNotModifiedWithContinuationTokens(documentContainer, enumerator)
: DrainUntilNotModifedAsync(enumerator));
Assert.AreEqual(numItems, globalCount);
}
private static async Task <int> DrainWithUntilNotModifiedWithContinuationTokens(
IDocumentContainer documentContainer,
CrossPartitionChangeFeedAsyncEnumerator enumerator)
{
List <CosmosElement> globalChanges = new List <CosmosElement>();
while (true)
{
if (!await enumerator.MoveNextAsync())
{
throw new InvalidOperationException();
}
Assert.IsTrue(enumerator.Current.Succeeded);
if (!(enumerator.Current.Result is ChangeFeedSuccessPage changeFeedSuccessPage))
{
break;
}
CosmosArray changes = GetChanges(changeFeedSuccessPage.Content);
globalChanges.AddRange(changes);
CosmosElement continuationToken = ((ChangeFeedStateContinuation)enumerator.Current.Result.State).ContinuationToken;
enumerator = CrossPartitionChangeFeedAsyncEnumerator.MonadicCreate(
documentContainer,
new ChangeFeedRequestOptions(),
ChangeFeedStartFrom.ContinuationToken(continuationToken.ToString()),
cancellationToken: default).Result;
}
return(globalChanges.Count);
}
public async Task NoChangesAsync()
{
IDocumentContainer documentContainer = await CreateDocumentContainerAsync(numItems : 0);
TryCatch <CrossPartitionChangeFeedAsyncEnumerator> monadicEnumerator = CrossPartitionChangeFeedAsyncEnumerator.MonadicCreate(
documentContainer,
new ChangeFeedRequestOptions(),
ChangeFeedStartFrom.Beginning(),
cancellationToken: default);
Assert.IsTrue(monadicEnumerator.Succeeded);
CrossPartitionChangeFeedAsyncEnumerator enumerator = monadicEnumerator.Result;
Assert.IsTrue(await enumerator.MoveNextAsync());
Assert.IsTrue(enumerator.Current.Succeeded);
Assert.IsTrue(enumerator.Current.Result is ChangeFeedNotModifiedPage);
Assert.IsNotNull(enumerator.Current.Result.State);
}
public async Task StartFromBeginningAsync(bool useContinuations)
{
int numItems = 100;
IDocumentContainer documentContainer = await CreateDocumentContainerAsync(numItems);
TryCatch <CrossPartitionChangeFeedAsyncEnumerator> monadicEnumerator = CrossPartitionChangeFeedAsyncEnumerator.MonadicCreate(
documentContainer,
new ChangeFeedRequestOptions(),
ChangeFeedStartFrom.Beginning(),
cancellationToken: default);
Assert.IsTrue(monadicEnumerator.Succeeded);
CrossPartitionChangeFeedAsyncEnumerator enumerator = monadicEnumerator.Result;
int globalCount = await(useContinuations
? DrainWithUntilNotModifiedWithContinuationTokens(documentContainer, enumerator)
: DrainUntilNotModifedAsync(enumerator));
Assert.AreEqual(numItems, globalCount);
}
public async Task SomeChangesAsync()
{
IDocumentContainer documentContainer = await CreateDocumentContainerAsync(numItems : 1);
TryCatch <CrossPartitionChangeFeedAsyncEnumerator> monadicEnumerator = CrossPartitionChangeFeedAsyncEnumerator.MonadicCreate(
documentContainer,
new ChangeFeedRequestOptions(),
ChangeFeedStartFrom.Beginning(),
cancellationToken: default);
Assert.IsTrue(monadicEnumerator.Succeeded);
CrossPartitionChangeFeedAsyncEnumerator enumerator = monadicEnumerator.Result;
// First page should be true and skip the 304 not modified
Assert.IsTrue(await enumerator.MoveNextAsync());
Assert.IsTrue(enumerator.Current.Succeeded);
Assert.IsTrue(enumerator.Current.Result is ChangeFeedSuccessPage);
// Second page should surface up the 304
Assert.IsTrue(await enumerator.MoveNextAsync());
Assert.IsTrue(enumerator.Current.Succeeded);
Assert.IsTrue(enumerator.Current.Result is ChangeFeedNotModifiedPage);
}
public ChangeFeedIteratorCore(
IDocumentContainer documentContainer,
ChangeFeedRequestOptions changeFeedRequestOptions,
ChangeFeedStartFrom changeFeedStartFrom)
{
if (changeFeedStartFrom == null)
{
throw new ArgumentNullException(nameof(changeFeedStartFrom));
}
this.documentContainer = documentContainer ?? throw new ArgumentNullException(nameof(documentContainer));
this.changeFeedRequestOptions = changeFeedRequestOptions ?? new ChangeFeedRequestOptions();
this.lazyMonadicEnumerator = new AsyncLazy <TryCatch <CrossPartitionChangeFeedAsyncEnumerator> >(
valueFactory: async(cancellationToken) =>
{
if (changeFeedStartFrom is ChangeFeedStartFromContinuation startFromContinuation)
{
TryCatch <CosmosElement> monadicParsedToken = CosmosElement.Monadic.Parse(startFromContinuation.Continuation);
if (monadicParsedToken.Failed)
{
return(TryCatch <CrossPartitionChangeFeedAsyncEnumerator> .FromException(
new MalformedChangeFeedContinuationTokenException(
message: $"Failed to parse continuation token: {startFromContinuation.Continuation}.",
innerException: monadicParsedToken.Exception)));
}
TryCatch <VersionedAndRidCheckedCompositeToken> monadicVersionedToken = VersionedAndRidCheckedCompositeToken
.MonadicCreateFromCosmosElement(monadicParsedToken.Result);
if (monadicVersionedToken.Failed)
{
return(TryCatch <CrossPartitionChangeFeedAsyncEnumerator> .FromException(
new MalformedChangeFeedContinuationTokenException(
message: $"Failed to parse continuation token: {startFromContinuation.Continuation}.",
innerException: monadicVersionedToken.Exception)));
}
VersionedAndRidCheckedCompositeToken versionedAndRidCheckedCompositeToken = monadicVersionedToken.Result;
if (versionedAndRidCheckedCompositeToken.VersionNumber == VersionedAndRidCheckedCompositeToken.Version.V1)
{
// Need to migrate continuation token
if (!(versionedAndRidCheckedCompositeToken.ContinuationToken is CosmosArray cosmosArray))
{
return(TryCatch <CrossPartitionChangeFeedAsyncEnumerator> .FromException(
new MalformedChangeFeedContinuationTokenException(
message: $"Failed to parse get array continuation token: {startFromContinuation.Continuation}.")));
}
List <CosmosElement> changeFeedTokensV2 = new List <CosmosElement>();
foreach (CosmosElement arrayItem in cosmosArray)
{
if (!(arrayItem is CosmosObject cosmosObject))
{
return(TryCatch <CrossPartitionChangeFeedAsyncEnumerator> .FromException(
new MalformedChangeFeedContinuationTokenException(
message: $"Failed to parse get object in composite continuation: {startFromContinuation.Continuation}.")));
}
if (!cosmosObject.TryGetValue("min", out CosmosString min))
{
return(TryCatch <CrossPartitionChangeFeedAsyncEnumerator> .FromException(
new MalformedChangeFeedContinuationTokenException(
message: $"Failed to parse start of range: {cosmosObject}.")));
}
if (!cosmosObject.TryGetValue("max", out CosmosString max))
{
return(TryCatch <CrossPartitionChangeFeedAsyncEnumerator> .FromException(
new MalformedChangeFeedContinuationTokenException(
message: $"Failed to parse end of range: {cosmosObject}.")));
}
if (!cosmosObject.TryGetValue("token", out CosmosElement token))
{
return(TryCatch <CrossPartitionChangeFeedAsyncEnumerator> .FromException(
new MalformedChangeFeedContinuationTokenException(
message: $"Failed to parse token: {cosmosObject}.")));
}
FeedRangeEpk feedRangeEpk = new FeedRangeEpk(new Documents.Routing.Range <string>(
min: min.Value,
max: max.Value,
isMinInclusive: true,
isMaxInclusive: false));
ChangeFeedState state = token is CosmosNull ? ChangeFeedState.Beginning() : ChangeFeedStateContinuation.Continuation(token);
ChangeFeedContinuationToken changeFeedContinuationToken = new ChangeFeedContinuationToken(feedRangeEpk, state);
changeFeedTokensV2.Add(ChangeFeedContinuationToken.ToCosmosElement(changeFeedContinuationToken));
}
CosmosArray changeFeedTokensArrayV2 = CosmosArray.Create(changeFeedTokensV2);
versionedAndRidCheckedCompositeToken = new VersionedAndRidCheckedCompositeToken(
VersionedAndRidCheckedCompositeToken.Version.V2,
changeFeedTokensArrayV2,
versionedAndRidCheckedCompositeToken.Rid);
}
if (versionedAndRidCheckedCompositeToken.VersionNumber != VersionedAndRidCheckedCompositeToken.Version.V2)
{
return(TryCatch <CrossPartitionChangeFeedAsyncEnumerator> .FromException(
new MalformedChangeFeedContinuationTokenException(
message: $"Wrong version number: {versionedAndRidCheckedCompositeToken.VersionNumber}.")));
}
string collectionRid = await documentContainer.GetResourceIdentifierAsync(cancellationToken);
if (versionedAndRidCheckedCompositeToken.Rid != collectionRid)
{
return(TryCatch <CrossPartitionChangeFeedAsyncEnumerator> .FromException(
new MalformedChangeFeedContinuationTokenException(
message: $"rids mismatched. Expected: {collectionRid} but got {versionedAndRidCheckedCompositeToken.Rid}.")));
}
changeFeedStartFrom = ChangeFeedStartFrom.ContinuationToken(versionedAndRidCheckedCompositeToken.ContinuationToken.ToString());
}
TryCatch <CrossPartitionChangeFeedAsyncEnumerator> monadicEnumerator = CrossPartitionChangeFeedAsyncEnumerator.MonadicCreate(
documentContainer,
changeFeedRequestOptions,
changeFeedStartFrom,
cancellationToken: default);
return(monadicEnumerator);
});
this.hasMoreResults = true;
}