Event Hubs Samples (#4053)

* Add hello world sample.

* Adding ReceiveEvent sample.

* Adding samples to the correct aggregate report.

* Adding sample for getting Event Hub metadata

eng/spotbugs-aggregate-report/pom.xml

@@ -54,7 +54,8 @@
                 <source>..\..\core\azure-core-auth\src\main\java</source>
                 <source>..\..\core\azure-core-management\src\main\java</source>
                 <source>..\..\core\azure-core-test\src\main\java</source>
-                <source>..\..\eventhubs\client\src\main\java</source>
+                <source>..\..\eventhubs\client\azure-eventhubs\src\main\java</source>
+                <source>..\..\eventhubs\client\azure-eventhubs\src\samples\java</source>
               </sources>
             </configuration>
           </execution>

eventhubs/client/azure-eventhubs/src/samples/java/GetEventHubMetadata.java

@@ -0,0 +1,49 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+import com.azure.messaging.eventhubs.EventHubClient;
+import com.azure.messaging.eventhubs.EventHubClientBuilder;
+
+import java.util.concurrent.Semaphore;
+
+/**
+ * Demonstrates how to fetch metadata from an Event Hub's partitions.
+ */
+public class GetEventHubMetadata {
+    public static void main(String[] args) throws InterruptedException {
+        Semaphore semaphore = new Semaphore(1);
+
+        // The connection string value can be obtained by:
+        // 1. Going to your Event Hubs namespace in Azure Portal.
+        // 2. Creating an Event Hub instance.
+        // 3. Creating a "Shared access policy" for your Event Hub instance.
+        // 4. Copying the connection string from the policy's properties.
+        String connectionString = "Endpoint={endpoint};SharedAccessKeyName={sharedAccessKeyName};SharedAccessKey={sharedAccessKey};EntityPath={eventHubPath}";
+
+        // Instantiate a client that will be used to call the service.
+        EventHubClient client = new EventHubClientBuilder()
+            .connectionString(connectionString)
+            .build();
+
+        // Acquiring the semaphore so that this sample does not end before all the partition properties are fetched.
+        semaphore.acquire();
+
+        // Querying the partition identifiers for the Event Hub. Then calling client.getPartitionProperties with the
+        // identifier to get information about each partition.
+        client.getPartitionIds().flatMap(partitionId -> client.getPartitionProperties(partitionId)).subscribe(properties -> {
+            System.out.println(String.format(
+                "Event Hub: %s, Partition Id: %s, Last Enqueued Sequence Number: %s, Last Enqueued Offset: %s",
+                properties.eventHubPath(), properties.id(), properties.lastEnqueuedSequenceNumber(),
+                properties.lastEnqueuedOffset()));
+        }, error -> {
+            System.err.println("Error occurred while fetching partition properties: " + error.toString());
+        }, () -> {
+            // Releasing the semaphore now that we've finished querying for partition properties.
+            semaphore.release();
+        });
+
+        System.out.println("Waiting for partition properties to complete...");
+        semaphore.acquire();
+        System.out.println("Finished.");
+    }
+}

eventhubs/client/azure-eventhubs/src/samples/java/ReceiveEvent.java

@@ -0,0 +1,86 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+import com.azure.messaging.eventhubs.EventData;
+import com.azure.messaging.eventhubs.EventHubClient;
+import com.azure.messaging.eventhubs.EventHubClientBuilder;
+import com.azure.messaging.eventhubs.EventHubConsumer;
+import com.azure.messaging.eventhubs.EventHubProducer;
+import com.azure.messaging.eventhubs.EventHubProducerOptions;
+import com.azure.messaging.eventhubs.EventPosition;
+import reactor.core.Disposable;
+import reactor.core.publisher.Flux;
+
+import java.io.IOException;
+import java.time.Duration;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+/**
+ * Sample demonstrates how to receive events from an Azure Event Hub instance.
+ */
+public class ReceiveEvent {
+    private static final Duration OPERATION_TIMEOUT = Duration.ofSeconds(30);
+    private static final int NUMBER_OF_EVENTS = 10;
+
+    public static void main(String[] args) throws InterruptedException, IOException {
+        CountDownLatch countDownLatch = new CountDownLatch(NUMBER_OF_EVENTS);
+
+        // The connection string value can be obtained by:
+        // 1. Going to your Event Hubs namespace in Azure Portal.
+        // 2. Creating an Event Hub instance.
+        // 3. Creating a "Shared access policy" for your Event Hub instance.
+        // 4. Copying the connection string from the policy's properties.
+        String connectionString = "Endpoint={endpoint};SharedAccessKeyName={sharedAccessKeyName};SharedAccessKey={sharedAccessKey};EntityPath={eventHubPath}";
+
+        // Instantiate a client that will be used to call the service.
+        EventHubClient client = new EventHubClientBuilder()
+            .connectionString(connectionString)
+            .build();
+
+        // To create a consumer, we need to know what partition to connect to. We take the first partition id.
+        // .blockFirst() here is used to synchronously block until the first partition id is emitted. The maximum wait
+        // time is set by passing in the OPERATION_TIMEOUT value. If no item is emitted before the timeout elapses, a
+        // TimeoutException is thrown.
+        String firstPartition = client.getPartitionIds().blockFirst(OPERATION_TIMEOUT);
+
+        // Create a consumer.
+        // The "$Default" consumer group is created by default. This value can be found by going to the Event Hub
+        // instance you are connecting to, and selecting the "Consumer groups" page. EventPosition.latest() tells the
+        // service we only want events that are sent to the partition after we begin listening.
+        EventHubConsumer consumer = client.createConsumer(EventHubClient.DEFAULT_CONSUMER_GROUP_NAME,
+            firstPartition, EventPosition.latest());
+
+        // We start receiving any events that come from `firstPartition`, print out the contents, and decrement the
+        // countDownLatch.
+        Disposable subscription = consumer.receive().subscribe(event -> {
+            String contents = UTF_8.decode(event.body()).toString();
+            System.out.println(String.format("[%s] Sequence Number: %s. Contents: %s", countDownLatch.getCount(),
+                event.offset(), contents));
+
+            countDownLatch.countDown();
+        });
+
+        // Because the consumer is only listening to new events, we need to send some events to `firstPartition`.
+        // This creates a producer that only sends events to `firstPartition`.
+        EventHubProducerOptions producerOptions = new EventHubProducerOptions().partitionId(firstPartition);
+        EventHubProducer producer = client.createProducer(producerOptions);
+
+        // We create 10 events to send to the service and block until the send has completed.
+        Flux.range(0, NUMBER_OF_EVENTS).flatMap(number -> {
+            String body = String.format("Hello world! Number: %s", number);
+            return producer.send(new EventData(body.getBytes(UTF_8)));
+        }).blockLast(OPERATION_TIMEOUT);
+
+        // We wait for all the events to be received before continuing.
+        countDownLatch.await(OPERATION_TIMEOUT.getSeconds(), TimeUnit.SECONDS);
+
+        // Dispose and close of all the resources we've created.
+        subscription.dispose();
+        producer.close();
+        consumer.close();
+        client.close();
+    }
+}

eventhubs/client/azure-eventhubs/src/samples/java/SendEvent.java

@@ -0,0 +1,63 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+import com.azure.core.amqp.exception.AmqpException;
+import com.azure.messaging.eventhubs.EventData;
+import com.azure.messaging.eventhubs.EventHubClient;
+import com.azure.messaging.eventhubs.EventHubClientBuilder;
+import com.azure.messaging.eventhubs.EventHubProducer;
+
+import java.io.IOException;
+
+import static java.nio.charset.StandardCharsets.UTF_8;
+
+/**
+ * Sample demonstrates how to send a message to an Azure Event Hub.
+ */
+public class SendEvent {
+    public static void main(String[] args) {
+        // The connection string value can be obtained by:
+        // 1. Going to your Event Hubs namespace in Azure Portal.
+        // 2. Creating an Event Hub instance.
+        // 3. Creating a "Shared access policy" for your Event Hub instance.
+        // 4. Copying the connection string from the policy's properties.
+        String connectionString = "Endpoint={endpoint};SharedAccessKeyName={sharedAccessKeyName};SharedAccessKey={sharedAccessKey};EntityPath={eventHubPath}";
+
+        // Instantiate a client that will be used to call the service.
+        EventHubClient client = new EventHubClientBuilder()
+            .connectionString(connectionString)
+            .build();
+
+        // Create a producer. This overload of `createProducer` does not accept any arguments. Consequently, events
+        // sent from this producer are load balanced between all available partitions in the Event Hub instance.
+        EventHubProducer producer = client.createProducer();
+
+        // Create an event to send.
+        EventData data = new EventData("Hello world!".getBytes(UTF_8));
+
+        // Send that event. This call returns a Mono<Void>, which we subscribe to. It completes successfully when the
+        // event has been delivered to the Event Hub. It completes with an error if an exception occurred while sending
+        // the event.
+        producer.send(data).subscribe(
+            (ignored) -> System.out.println("Event sent."),
+            error -> {
+                System.err.println("There was an error sending the event: " + error.toString());
+
+                if (error instanceof AmqpException) {
+                    AmqpException amqpException = (AmqpException) error;
+
+                    System.err.println(String.format("Is send operation retriable? %s. Error condition: %s",
+                        amqpException.isTransient(), amqpException.getErrorCondition()));
+                }
+            }, () -> {
+                // Disposing of our producer and client.
+                try {
+                    producer.close();
+                } catch (IOException e) {
+                    System.err.println("Error encountered while closing producer: " + e.toString());
+                }
+
+                client.close();
+            });
+    }
+}

pom.client.xml

@@ -512,6 +512,7 @@
               <additionalOptions>-maxLineLength 120
                 -snippetpath ${project.basedir}/applicationconfig/client/src/samples/java
                 -snippetpath ${project.basedir}/core/azure-core/src/samples/java
+                -snippetpath ${project.basedir}/eventhubs/client/azure-eventhubs/src/samples/java
                 -snippetpath ${project.basedir}/keyvault/client/keys/src/samples/java
                 -snippetpath ${project.basedir}/keyvault/client/secrets/src/samples/java
               </additionalOptions>