public void TestConsumer()
{
var client = new Mock <IClusterClient>();
client.SetupGet(c => c.Messages)
.Returns(Observable.FromEvent <RawKafkaRecord>(a => client.Object.MessageReceived += a,
a => client.Object.MessageReceived -= a));
// Bad arguments
Assert.That(() => new KafkaConsumer <string, string>(null, client.Object), Throws.ArgumentException);
Assert.That(() => new KafkaConsumer <string, string>("", client.Object), Throws.ArgumentException);
Assert.That(() => new KafkaConsumer <string, string>("toto", null), Throws.InstanceOf <ArgumentNullException>());
using (var consumer = new KafkaConsumer <string, string>("topic", client.Object))
{
// Double new on same topic/TKey/TValue
Assert.That(() => new KafkaConsumer <string, string>("topic", client.Object), Throws.ArgumentException);
// Consume / Stop
consumer.Consume(2, 42);
consumer.ConsumeFromLatest();
consumer.ConsumeFromLatest(2);
consumer.ConsumeFromEarliest();
consumer.ConsumeFromEarliest(2);
consumer.StopConsume();
consumer.StopConsume(2);
consumer.StopConsume(2, 42);
client.Verify(c => c.Consume(It.IsAny <string>(), It.IsAny <int>(), It.IsAny <long>()), Times.Once());
client.Verify(c => c.StopConsume("topic", 2, 42));
client.Verify(c => c.ConsumeFromLatest(It.IsAny <string>()), Times.Once());
client.Verify(c => c.ConsumeFromLatest("topic"));
client.Verify(c => c.ConsumeFromLatest(It.IsAny <string>(), It.IsAny <int>()), Times.Once());
client.Verify(c => c.ConsumeFromLatest("topic", 2));
client.Verify(c => c.ConsumeFromEarliest(It.IsAny <string>()), Times.Once());
client.Verify(c => c.ConsumeFromEarliest("topic"));
client.Verify(c => c.ConsumeFromEarliest(It.IsAny <string>(), It.IsAny <int>()), Times.Once());
client.Verify(c => c.ConsumeFromEarliest("topic", 2));
client.Verify(c => c.StopConsume(It.IsAny <string>()), Times.Once());
client.Verify(c => c.StopConsume("topic"));
client.Verify(c => c.StopConsume(It.IsAny <string>(), It.IsAny <int>()), Times.Once());
client.Verify(c => c.StopConsume("topic", 2));
client.Verify(c => c.StopConsume(It.IsAny <string>(), It.IsAny <int>(), It.IsAny <long>()), Times.Once());
client.Verify(c => c.StopConsume("topic", 2, 42));
bool messageObserved = false;
bool messageEvent = false;
KafkaRecord <string, string> received = default(KafkaRecord <string, string>);
consumer.MessageReceived += kr =>
{
received = kr;
messageEvent = true;
};
consumer.Messages.Subscribe(kr =>
{
messageObserved = true;
});
var record = new RawKafkaRecord
{
Topic = "topic",
Key = "key",
Value = "data",
Partition = 2,
Offset = 42
};
client.Raise(c => c.MessageReceived += null, record);
Assert.IsTrue(messageEvent);
Assert.IsTrue(messageObserved);
Assert.AreEqual("topic", received.Topic);
Assert.AreEqual("key", received.Key);
Assert.AreEqual("data", received.Value);
Assert.AreEqual(2, received.Partition);
Assert.AreEqual(42, received.Offset);
record.Key = null;
messageObserved = false;
messageEvent = false;
received = default(KafkaRecord <string, string>);
client.Raise(c => c.MessageReceived += null, record);
Assert.IsTrue(messageEvent);
Assert.IsTrue(messageObserved);
Assert.IsTrue(messageEvent);
Assert.IsTrue(messageObserved);
Assert.AreEqual("topic", received.Topic);
Assert.IsNull(received.Key);
Assert.AreEqual("data", received.Value);
Assert.AreEqual(2, received.Partition);
Assert.AreEqual(42, received.Offset);
}
// Dispose: can register another producer with same Topic/TKey/TValue once
// the previous one has been disposed.
client = new Mock <IClusterClient>();
client.SetupGet(c => c.Messages)
.Returns(Observable.FromEvent <RawKafkaRecord>(a => client.Object.MessageReceived += a,
a => client.Object.MessageReceived -= a));
var consumer2 = new KafkaConsumer <string, string>("topic", client.Object);
// Dispose: observable are completed and events no longer subscribed
bool messageCompleted = false;
bool messageEvent2 = false;
consumer2.Messages.Subscribe(kr => { }, () => messageCompleted = true);
consumer2.MessageReceived += _ => messageEvent2 = true;
consumer2.Dispose();
client.Verify(c => c.StopConsume(It.IsAny <string>()), Times.Once()); // Dispose stops all
client.Verify(c => c.StopConsume("topic"), Times.Once());
var record2 = new RawKafkaRecord
{
Topic = "topic",
Key = "key",
Value = "data",
Partition = 2,
Offset = 42
};
client.Raise(c => c.MessageReceived += null, record2);
Assert.IsTrue(messageCompleted);
Assert.IsFalse(messageEvent2);
// Consume / Stop no longer work
consumer2.Consume(2, 42);
consumer2.ConsumeFromLatest();
consumer2.ConsumeFromLatest(2);
consumer2.ConsumeFromEarliest();
consumer2.ConsumeFromEarliest(2);
consumer2.StopConsume();
consumer2.StopConsume(2);
consumer2.StopConsume(2, 42);
client.Verify(c => c.Consume(It.IsAny <string>(), It.IsAny <int>(), It.IsAny <long>()), Times.Never());
client.Verify(c => c.ConsumeFromLatest(It.IsAny <string>()), Times.Never());
client.Verify(c => c.ConsumeFromLatest(It.IsAny <string>(), It.IsAny <int>()), Times.Never());
client.Verify(c => c.ConsumeFromEarliest(It.IsAny <string>()), Times.Never());
client.Verify(c => c.ConsumeFromEarliest(It.IsAny <string>(), It.IsAny <int>()), Times.Never());
client.Verify(c => c.StopConsume(It.IsAny <string>()), Times.Once());
client.Verify(c => c.StopConsume(It.IsAny <string>(), It.IsAny <int>()), Times.Never());
client.Verify(c => c.StopConsume(It.IsAny <string>(), It.IsAny <int>(), It.IsAny <long>()), Times.Never());
// Dispose: can dispose the same consumer multiple times with no effect
Assert.That(() => consumer2.Dispose(), Throws.Nothing);
}