Inconsistent headers transport (SQS specific issue?)

Is this a bug report?

YES.

Can you also reproduce the problem with the latest version?

YES.

Steps to Reproduce

1. Create a typical message customer throwing exception.
2. Add .UseScheduledRedelivery() filter.
3. Send a message. It should fail several times and then be moved on the error queue.

Expected Behavior

MT adds a tone of useful headers to the message, all starting with the prefix MT-*. They should all appear in message’s payload Headers property as well as in SQS’s “message attributes” unless this newly added AllowTransportHeader filter states otherwise.

Actual Behavior

Actual message on the queue has some headers only in message body and some only in message attributes:

Payload:

{
  "messageId": "eb800000-857f-0205-2274-08d7822ceb48",
  "conversationId": "eb800000-857f-0205-3ea1-08d7822ce6fd",
  "sourceAddress": "amazonsqs://eu-central-1/my-tmp?durable=false&autodelete=true",
  "destinationAddress": "amazonsqs://eu-central-1/dev-krzlab-plgrd-rec",
  "messageType": [
    "urn:message:WebApp:MyMsg"
  ],
  "message": {
    "payload": "throw"
  },
  "sentTime": "2019-12-16T13:36:13.3759604Z",
  "headers": {
    "MT-Scheduling-DeliveredAddress": "amazonsqs://eu-central-1/dev-krzlab-plgrd-rec",
    "MT-Redelivery-Count": 3
  },
  "host": {
    ...
  }
}

Message Attributes:

Content-Type: application/vnd.masstransit+json
MT-Fault-Message: EXCEPTION MESSAGE
MT-Reason: fault

Reproducible Demo

c.AddBus(provider => Bus.Factory.CreateUsingAmazonSqs(bfc =>
{
    bfc.UseAmazonSqsMessageScheduler();
    
    bfc.Host("eu-central-1", hc =>
    {
        hc.AccessKey("...");
        hc.SecretKey("...");
    });

    bfc.ReceiveEndpoint("dev-krzlab-plgrd-rec", rec =>
    {
        rec.UseScheduledRedelivery(r => r.Interval(3, TimeSpan.FromSeconds(2)));
        rec.UseInMemoryOutbox();
        rec.Consumer<MyMsgConsumer>(provider);
    });
}));

public class MyMsgConsumer : IConsumer<MyMsg>
{
    public async Task Consume(ConsumeContext<MyMsg> context)
    {
        throw new Exception("EXCEPTION MESSAGE");
    }
}

[Crozin]

Can’t find anything else at the moment. 😃

[phatboyg]

Is there anything else to do on this one?