More extensibility or configurability to prevent need of service-specific publishers

[brendonparker]

I really like the cleanliness of IMessagePublisher.
But it lacks (rightly so) any knowledge of whether the message is for SNS or SQS or is Standard or FIFO.

For example: if I have a message bound to a FIFO queue, I need to set the MessageGroupId. If I try and send that message using the IMessagePublisher it fails with

AWS.Messaging.InvalidFifoPublishingRequestException: You are attempting to send to a FIFO SQS queue but the request does not include a message group ID. Please use ISQSPublisher from the service collection to send to FIFO queues. It exposes a SendAsync method that accepts SQSOptions as a parameter. A message group ID must be specified via MessageGroupId. Additionally, MessageDeduplicationId must also be specified if content based de-duplication is not enabled on the queue.

Which is a great error message! But the prescribed solution kinda stinks.

What if there were some form of middleware that could be injected to tweak the message prior to sending it? For example, to add/set the MessageGroupId. This would allow more flexibility to continue to use IMessagePublisher without needing to know to use ISQSPublisher.

Or some configuration when the type is registered like:

interface Tenant
{
    public string TenantId { get; }
}

class MyMessage : ITenant
{
    public required string TenantId { get; init; }
}

builder.AddSQSPublisher<MyMessage>(QUEUE_URL, onSend: envelope => {
    envelope.SQSMetadata.MessageGroupId = envelope.Message.TenantId;
));

[brendonparker]

I've hacked in an example of how this might working in this repository:

https://github.com/brendonparker/aws-dotnet-messaging-demo