Client hangs when calling Azure Event Hub and facing connection error

问题

I want to send event messages to Azure Event Hub. I noticed if I misconfigured something then my app hangs and not terminates.
I wrote a very simple Java class that tries to send event message to the Event Hub. If I mistype the endpoint of the Event Hub then the app hangs. Which is pretty disappointing.

There is a chance that I misunderstand something but what I want to do is to send a simple message and that's all. How can I do that?

    ConnectionStringBuilder connectionStringBuilder = new ConnectionStringBuilder();
    connectionStringBuilder
            .setEndpoint(URI.create("https://XXXXXXXXX.servsssicebus.windows.net"))
            .setTransportType(TransportType.AMQP_WEB_SOCKETS)
            .setSasKeyName("XXX")
            .setSasKey("XXX");
    ScheduledExecutorService scheduledExecutorService = Executors.newSingleThreadScheduledExecutor();
    final EventHubClient ehClient =
            EventHubClient.createFromConnectionStringSync(
                    connectionStringBuilder.toString(),
                    RetryPolicy.getNoRetry(),
                    scheduledExecutorService
            );
    ehClient.sendSync(EventData.create("Test Message".getBytes()));
    ehClient.closeSync();
    scheduledExecutorService.shutdown();

I use the following dependency:

    compile "com.microsoft.azure:azure-eventhubs:3.2.0"

I'd appreciate any help! Thanks!

回答1:

I use Maven to create a java project, then add dependency in pom.xml:

<dependency>
    <groupId>com.microsoft.azure</groupId>
    <artifactId>azure-eventhubs</artifactId>
    <version>2.2.0</version>
</dependency>
<dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
    <version>2.8.6</version>
</dependency>

And This is the code to send the event message:

package test;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.microsoft.azure.eventhubs.ConnectionStringBuilder;
import com.microsoft.azure.eventhubs.EventData;
import com.microsoft.azure.eventhubs.EventHubClient;
import com.microsoft.azure.eventhubs.EventHubException;
import java.io.IOException;
import java.nio.charset.Charset;
import java.time.Instant;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
public class App
{
    public static void main( String[] args ) throws Exception
    {
        final ConnectionStringBuilder connStr = new ConnectionStringBuilder()
                .setNamespaceName("testbowman")
                .setEventHubName("test")
                .setSasKeyName("testbowman")
                .setSasKey("xxxxxx");
        final Gson gson = new GsonBuilder().create();
        final ScheduledExecutorService executorService = Executors.newScheduledThreadPool(4);
        final EventHubClient ehClient = EventHubClient.createSync(connStr.toString(), executorService);

        try {
            for (int i = 0; i < 10; i++) {
                String payload = "Message " + Integer.toString(i);
                byte[] payloadBytes = gson.toJson(payload).getBytes(Charset.defaultCharset());
                EventData sendEvent = EventData.create(payloadBytes);
                ehClient.sendSync(sendEvent);
            }
            System.out.println(Instant.now() + ": Send Complete...");
            System.out.println("Press Enter to stop.");
            System.in.read();
        } finally {
            ehClient.closeSync();
            executorService.shutdown();
        }
        System.out.println( "Hello World!" );
        System.out.println( "!!!!!!!!!!!!!" );
    }
}

(I hide the sas key, I think you know where to get the sas key.:))

At last, I can see the messages come in on the metrics(Can not see immediately, need wait a few time.):

This is the offcial doc:

https://docs.microsoft.com/en-us/azure/event-hubs/event-hubs-java-get-started-send#write-code-to-send-events

回答2:

Try using work-stealing pool instead of single thread.

final ExecutorService scheduledExecutorService = Executors.newWorkStealingPool();

Or thread pool.

final ScheduledExecutorService scheduledExecutorService = Executors.newScheduledThreadPool(4);

来源：https://stackoverflow.com/questions/63039023/client-hangs-when-calling-azure-event-hub-and-facing-connection-error

标签

java

azure

azure-eventhub