public async Task SourceWithOffsetContext_at_least_once_consuming_should_work()
{
var topic = CreateTopic(1);
var settings = CreateConsumerSettings <string>(CreateGroup(1));
var elementCount = 10;
var batchSize = 2;
var messages = Enumerable.Range(1, elementCount).ToList();
await ProduceStrings(topic, messages, ProducerSettings);
var committerSettings = CommitterSettings.WithMaxBatch(batchSize);
var(control, probe) = KafkaConsumer.SourceWithOffsetContext(settings, Subscriptions.Topics(topic))
.SelectAsync(10, message => Task.FromResult(Done.Instance))
.Via(Committer.FlowWithOffsetContext <Done>(committerSettings))
.AsSource()
.ToMaterialized(this.SinkProbe <(NotUsed, ICommittableOffsetBatch)>(), Keep.Both)
.Run(Materializer);
probe.Request(10);
var committedBatches = probe.Within(TimeSpan.FromSeconds(10), () => probe.ExpectNextN(elementCount / batchSize));
probe.Cancel();
AwaitCondition(() => control.IsShutdown.IsCompletedSuccessfully, TimeSpan.FromSeconds(10));
committedBatches.Select(r => r.Item2).Sum(batch => batch.BatchSize).Should().Be(10);
}
public static async Task Main(string[] args)
{
Config fallbackConfig = ConfigurationFactory.ParseString(@"
akka.suppress-json-serializer-warning=true
akka.loglevel = DEBUG
").WithFallback(ConfigurationFactory.FromResource <ConsumerSettings <object, object> >("Akka.Streams.Kafka.reference.conf"));
var system = ActorSystem.Create("TestKafka", fallbackConfig);
var materializer = system.Materializer();
var consumerSettings = ConsumerSettings <Null, string> .Create(system, null, null)
.WithBootstrapServers($"{EventHubNamespace}.servicebus.windows.net:9093")
.WithGroupId(EventHubConsumerGroup)
.WithProperties(new Dictionary <string, string>
{
{ "security.protocol", "SASL_SSL" },
{ "sasl.mechanism", "PLAIN" },
{ "sasl.username", "$ConnectionString" },
{ "sasl.password", EventHubConnectionString },
});
var subscription = Subscriptions.Topics(EventHubName);
var committerDefaults = CommitterSettings.Create(system);
// Comment for simple no-commit consumer
DrainingControl <NotUsed> control = KafkaConsumer.CommittableSource(consumerSettings, subscription)
.SelectAsync(1, msg =>
Business(msg.Record).ContinueWith(done => (ICommittable)msg.CommitableOffset))
.ToMaterialized(
Committer.Sink(committerDefaults.WithMaxBatch(1)),
DrainingControl <NotUsed> .Create)
.Run(materializer);
// Uncomment for simple no-commit consumer
/*
* await KafkaConsumer.PlainSource(consumerSettings, subscription)
* .RunForeach(result =>
* {
* Console.WriteLine($"Consumer: {result.Topic}/{result.Partition} {result.Offset}: {result.Value}");
* }, materializer);
*/
Console.WriteLine("Press any key to stop consumer.");
Console.ReadKey();
// Comment for simple no-commit consumer
await control.Stop();
await system.Terminate();
}
public async Task CommitterFlow_commits_offsets_from_CommittableSource(int batchSize)
{
var topic1 = CreateTopic(1);
var topicPartition1 = new TopicPartition(topic1, 0);
var group1 = CreateGroup(1);
await GivenInitializedTopic(topicPartition1);
await Source
.From(Enumerable.Range(1, 100))
.Select(elem => new ProducerRecord <Null, string>(topicPartition1, elem.ToString()))
.RunWith(KafkaProducer.PlainSink(ProducerSettings), Materializer);
var consumerSettings = CreateConsumerSettings <string>(group1);
var committedElements = new ConcurrentQueue <string>();
var committerSettings = CommitterSettings.WithMaxBatch(batchSize);
var(task, probe1) = KafkaConsumer.CommittableSource(consumerSettings, Subscriptions.Assignment(topicPartition1))
.WhereNot(c => c.Record.Value == InitialMsg)
.SelectAsync(10, elem =>
{
committedElements.Enqueue(elem.Record.Value);
return(Task.FromResult(elem.CommitableOffset as ICommittable));
})
.Via(Committer.Flow(committerSettings))
.ToMaterialized(this.SinkProbe <Done>(), Keep.Both)
.Run(Materializer);
probe1.Request(25 / batchSize);
foreach (var _ in Enumerable.Range(1, 25 / batchSize))
{
probe1.ExpectNext(Done.Instance, TimeSpan.FromSeconds(10));
}
probe1.Cancel();
AwaitCondition(() => task.IsShutdown.IsCompletedSuccessfully);
var probe2 = KafkaConsumer.PlainSource(consumerSettings, Subscriptions.Assignment(new TopicPartition(topic1, 0)))
.Select(_ => _.Value)
.RunWith(this.SinkProbe <string>(), Materializer);
probe2.Request(75);
foreach (var i in Enumerable.Range(committedElements.Count + 1, 75).Select(c => c.ToString()))
{
probe2.ExpectNext(i, TimeSpan.FromSeconds(10));
}
probe2.Cancel();
}
/// <summary>
/// Batches offsets and commits them to Kafka.
/// </summary>
public static Sink <ICommittable, Task> Sink(CommitterSettings settings)
{
return(Flow(settings).ToMaterialized(Streams.Dsl.Sink.Ignore <Done>(), Keep.Right));
}
public static FlowWithContext <ICommittableOffset, E, ICommittableOffsetBatch, NotUsed, NotUsed> FlowWithOffsetContext <E>(CommitterSettings settings)
{
var value = Akka.Streams.Dsl.Flow.Create <(E, ICommittableOffset)>()
.Select(m => m.Item2 as ICommittable)
.Via(BatchFlow(settings))
.Select(b => (NotUsed.Instance, b));
return(FlowWithContext.From(value));
}
/// <summary>
/// Batches offsets and commits them to Kafka, emits <see cref="Done.Instance"/> for every committed batch.
/// </summary>
public static Flow <ICommittable, Done, NotUsed> Flow(CommitterSettings settings)
{
return(BatchFlow(settings).Select(_ => Done.Instance));
}
/// <summary>
/// Batches offsets and commits them to Kafka, emits <see cref="CommittableOffsetBatch"/> for every committed batch.
/// </summary>
public static Flow <ICommittable, ICommittableOffsetBatch, NotUsed> BatchFlow(CommitterSettings settings)
{
return(Akka.Streams.Dsl.Flow.Create <ICommittable>().GroupedWithin(settings.MaxBatch, settings.MaxInterval)
.Select(CommittableOffsetBatch.Create)
.SelectAsync(settings.Parallelism, async batch =>
{
await batch.Commit();
return batch;
}));
}
public async Task SupervisionStrategy_Decider_on_complex_stream_should_work()
{
var topic = CreateTopic(1);
var group = CreateGroup(1);
var topicPartition = new TopicPartition(topic, 0);
var committedTopicPartition = new TopicPartition($"{topic}-done", 0);
var callCount = 0;
Directive Decider(Exception cause)
{
callCount++;
return(Directive.Resume);
}
var committerSettings = CommitterSettings.Create(Sys);
var consumerSettings = CreateConsumerSettings <string>(group);
var counter = 0;
// arrange
await Source.From(Enumerable.Range(1, 10))
.Select(elem => new ProducerRecord <Null, string>(topicPartition, elem.ToString()))
.RunWith(KafkaProducer.PlainSink(ProducerSettings), Materializer);
// act
var drainingControl = KafkaConsumer.CommittableSource(consumerSettings, Subscriptions.Assignment(topicPartition))
.Via(Flow.Create <CommittableMessage <Null, string> >().Select(x =>
{
counter++;
// Exception happened here, fail once, when counter is 5
if (counter == 5)
{
throw new Exception("BOOM!");
}
return(x);
}))
.WithAttributes(Attributes.CreateName("CommitableSource").And(ActorAttributes.CreateSupervisionStrategy(Decider)))
.Select(c => (c.Record.Topic, c.Record.Message.Value, c.CommitableOffset))
.SelectAsync(1, async t =>
{
Log.Info($"[{t.Topic}]: {t.Value}");
// simulate a request-response call that takes 10ms to complete here
await Task.Delay(10);
return(t);
})
.Select(t => ProducerMessage.Single(new ProducerRecord <Null, string>(committedTopicPartition, t.Value),
t.CommitableOffset))
.Via(KafkaProducer.FlexiFlow <Null, string, ICommittableOffset>(ProducerSettings)).WithAttributes(Attributes.CreateName("FlexiFlow"))
.Select(m => (ICommittable)m.PassThrough)
.AlsoToMaterialized(Committer.Sink(committerSettings), DrainingControl <NotUsed> .Create)
.To(Flow.Create <ICommittable>()
.Async()
.GroupedWithin(1000, TimeSpan.FromSeconds(1))
.Select(c => c.Count())
.Log("MsgCount").AddAttributes(Attributes.CreateLogLevels(LogLevel.InfoLevel))
.To(Sink.Ignore <int>()))
.Run(Sys.Materializer());
await Task.Delay(TimeSpan.FromSeconds(5));
await GuardWithTimeoutAsync(drainingControl.DrainAndShutdown(), TimeSpan.FromSeconds(10));
// There should be only 1 decider call
callCount.Should().Be(1);
// Assert that all of the messages, except for those that failed in the stage, got committed
var settings = CreateConsumerSettings <Null, string>(group);
var probe = KafkaConsumer
.PlainSource(settings, Subscriptions.Assignment(committedTopicPartition))
.Select(c => c.Message.Value)
.RunWith(this.SinkProbe <string>(), Materializer);
probe.Request(9);
var messages = new List <string>();
for (var i = 0; i < 9; ++i)
{
var message = probe.RequestNext();
messages.Add(message);
}
// Message "5" is missing because the exception happened downstream of the source and we chose to
// ignore it in the decider
messages.Should().BeEquivalentTo(new[] { "1", "2", "3", "4", "6", "7", "8", "9", "10" });
probe.Cancel();
}
