# Native message access




## Access to the native Azure Service Bus incoming message

It can sometimes be useful to access the native Service Bus incoming message from behaviors and handlers. When a message is received, the transport adds the native Service Bus [`Message`](https://learn.microsoft.com/en-us/dotnet/api/microsoft.azure.servicebus.message) to the message processing context. Use the code below to access the message details from a [pipeline behavior](/nservicebus/pipeline/manipulate-with-behaviors.md):

<!-- snippet: access-native-incoming-message -->

```cs
class DoNotAttemptMessageProcessingIfMessageIsNotLocked
  : Behavior<ITransportReceiveContext>
{
    public override Task Invoke(ITransportReceiveContext context, Func<Task> next)
    {
        var nativeMessage = context.Extensions.Get<ServiceBusReceivedMessage>();
        
        if (nativeMessage.LockedUntil <= DateTime.UtcNow)
        {
            return next();
        }

        throw new Exception($"Message lock lost for MessageId {context.Message.MessageId} and it cannot be processed.");
    }
}
```

<!-- endsnippet -->

The behavior above uses the native message's `LockedUntilUtc` system property to determine where the message lost its lock as a result of aggressive prefetching and slow processing. If desired, a [custom recoverability policy](/nservicebus/recoverability/custom-recoverability-policy.md) can be used so that the message will skip attempted retry processing that otherwise would be guaranteed to fail due to the message's lost lock.

## Access to the native Azure Service Bus outgoing message

It can also be useful to access the native Service Bus outgoing message from behaviors and handlers for customizations.

<!-- snippet: access-native-outgoing-message -->

```cs
// send a command
var sendOptions = new SendOptions();
sendOptions.CustomizeNativeMessage(m => m.Subject = "custom-label");
await context.Send(new MyCommand(), sendOptions);

// publish an event
var publishOptions = new PublishOptions();
publishOptions.CustomizeNativeMessage(m => m.Subject = "custom-label");
await context.Publish(new MyEvent(), publishOptions);
```

<!-- endsnippet -->

Or on a more global level directly on the transport

<!-- snippet: access-native-outgoing-message-over-transport -->

```cs
transport.OutgoingNativeMessageCustomization = (operation, message) =>
{
    // Customize the outgoing message based on the operation
};
```

<!-- endsnippet -->

> [!NOTE]
> Native outgoing messages cannot be customized when using the [outbox](/nservicebus/outbox/index.md) as customizations are not persistent.