Azure Eventhub Dotnet

using Azure.Identity;using Azure.Messaging.EventHubs;using Azure.Messaging.EventHubs.Producer;
// Local dev: DefaultAzureCredential. Production: set AZURE_TOKEN_CREDENTIALS=prod or AZURE_TOKEN_CREDENTIALS=<specific_credential>var credential = new DefaultAzureCredential(    DefaultAzureCredential.DefaultEnvironmentVariableName);// Or use a specific credential directly in production:// See https://learn.microsoft.com/dotnet/api/overview/azure/identity-readme?view=azure-dotnet#credential-classes// var credential = new ManagedIdentityCredential();
var fullyQualifiedNamespace = Environment.GetEnvironmentVariable("EVENTHUB_FULLY_QUALIFIED_NAMESPACE");var eventHubName = Environment.GetEnvironmentVariable("EVENTHUB_NAME");
var producer = new EventHubProducerClient(    fullyQualifiedNamespace,    eventHubName,    credential);

using Azure.Identity;using Azure.Messaging.EventHubs;using Azure.Messaging.EventHubs.Producer;
await using var producer = new EventHubProducerClient(    fullyQualifiedNamespace,    eventHubName,    new DefaultAzureCredential());
// Create a batch (respects size limits automatically)using EventDataBatch batch = await producer.CreateBatchAsync();
// Add events to batchvar events = new[]{    new EventData(BinaryData.FromString("{\"id\": 1, \"message\": \"Hello\"}")),    new EventData(BinaryData.FromString("{\"id\": 2, \"message\": \"World\"}"))};
foreach (var eventData in events){    if (!batch.TryAdd(eventData))    {        // Batch is full - send it and create a new one        await producer.SendAsync(batch);        batch = await producer.CreateBatchAsync();                if (!batch.TryAdd(eventData))        {            throw new Exception("Event too large for empty batch");        }    }}
// Send remaining eventsif (batch.Count > 0){    await producer.SendAsync(batch);}

using Azure.Messaging.EventHubs.Producer;
var options = new EventHubBufferedProducerClientOptions{    MaximumWaitTime = TimeSpan.FromSeconds(1)};
await using var producer = new EventHubBufferedProducerClient(    fullyQualifiedNamespace,    eventHubName,    new DefaultAzureCredential(),    options);
// Handle send success/failureproducer.SendEventBatchSucceededAsync += args =>{    Console.WriteLine($"Batch sent: {args.EventBatch.Count} events");    return Task.CompletedTask;};
producer.SendEventBatchFailedAsync += args =>{    Console.WriteLine($"Batch failed: {args.Exception.Message}");    return Task.CompletedTask;};
// Enqueue events (sent automatically in background)for (int i = 0; i < 1000; i++){    await producer.EnqueueEventAsync(new EventData($"Event {i}"));}
// Flush remaining events before disposingawait producer.FlushAsync();

using Azure.Identity;using Azure.Messaging.EventHubs;using Azure.Messaging.EventHubs.Consumer;using Azure.Messaging.EventHubs.Processor;using Azure.Storage.Blobs;
// Blob container for checkpointingvar blobClient = new BlobContainerClient(    Environment.GetEnvironmentVariable("BLOB_STORAGE_CONNECTION_STRING"),    Environment.GetEnvironmentVariable("BLOB_CONTAINER_NAME"));
await blobClient.CreateIfNotExistsAsync();
// Create processorvar processor = new EventProcessorClient(    blobClient,    EventHubConsumerClient.DefaultConsumerGroup,    fullyQualifiedNamespace,    eventHubName,    new DefaultAzureCredential());
// Handle eventsprocessor.ProcessEventAsync += async args =>{    Console.WriteLine($"Partition: {args.Partition.PartitionId}");    Console.WriteLine($"Data: {args.Data.EventBody}");        // Checkpoint after processing (or batch checkpoints)    await args.UpdateCheckpointAsync();};
// Handle errorsprocessor.ProcessErrorAsync += args =>{    Console.WriteLine($"Error: {args.Exception.Message}");    Console.WriteLine($"Partition: {args.PartitionId}");    return Task.CompletedTask;};
// Start processingawait processor.StartProcessingAsync();
// Run until cancelledawait Task.Delay(Timeout.Infinite, cancellationToken);
// Stop gracefullyawait processor.StopProcessingAsync();

// Get partition IDsstring[] partitionIds = await producer.GetPartitionIdsAsync();
// Send to specific partition (use sparingly)var options = new SendEventOptions{    PartitionId = "0"};await producer.SendAsync(events, options);
// Use partition key (recommended for ordering)var batchOptions = new CreateBatchOptions{    PartitionKey = "customer-123"  // Events with same key go to same partition};using var batch = await producer.CreateBatchAsync(batchOptions);

// Start from beginningEventPosition.Earliest
// Start from end (new events only)EventPosition.Latest
// Start from specific offsetEventPosition.FromOffset(12345)
// Start from specific sequence numberEventPosition.FromSequenceNumber(100)
// Start from specific timeEventPosition.FromEnqueuedTime(DateTimeOffset.UtcNow.AddHours(-1))

// Program.csusing Azure.Identity;using Azure.Messaging.EventHubs.Producer;using Microsoft.Extensions.Azure;
builder.Services.AddAzureClients(clientBuilder =>{    clientBuilder.AddEventHubProducerClient(        builder.Configuration["EventHub:FullyQualifiedNamespace"],        builder.Configuration["EventHub:Name"]);        clientBuilder.UseCredential(new DefaultAzureCredential());});
// Inject in controller/servicepublic class EventService{    private readonly EventHubProducerClient _producer;        public EventService(EventHubProducerClient producer)    {        _producer = producer;    }        public async Task SendAsync(string message)    {        using var batch = await _producer.CreateBatchAsync();        batch.TryAdd(new EventData(message));        await _producer.SendAsync(batch);    }}

using Azure.Messaging.EventHubs;
try{    await producer.SendAsync(batch);}catch (EventHubsException ex) when (ex.Reason == EventHubsException.FailureReason.ServiceBusy){    // Retry with backoff    await Task.Delay(TimeSpan.FromSeconds(5));}catch (EventHubsException ex) when (ex.IsTransient){    // Transient error - safe to retry    Console.WriteLine($"Transient error: {ex.Message}");}catch (EventHubsException ex){    // Non-transient error    Console.WriteLine($"Error: {ex.Reason} - {ex.Message}");}

// Checkpoint every 100 eventsprivate int _eventCount = 0;
processor.ProcessEventAsync += async args =>{    // Process event...        _eventCount++;    if (_eventCount >= 100)    {        await args.UpdateCheckpointAsync();        _eventCount = 0;    }};