MediatR async handlers without await

[afoxtrident]

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Hello,

If you have a create command without any return type the method is generated as async, however doesn't await or complete any task (as below)

public async Task Handle(CreateItemCommand request, CancellationToken cancellationToken)
{
    var item= new Item
    {
        Id = request.Id,
        Value = request.Value
    };

    _repository.Add(item);
}

Would it be possible to change methods like these to remove the async keyword, and return Task.CompletedTask ?

According to AI benchmarks its considerably quicker if we return a task.

[jp-seini]

Hi @afoxsonoco - thanks for raising this.

This definitely looks like something we can address - I will create a ticket for our backlog.

In the meantime, if the performance is an urgent issue, you can change the mode of the method to fully control it (you do however lose the functionality of Intent automatically coding the mapping for you then in the method)

[IntentManaged(Mode.Ignore)]
public Task Handle(CreateItemCommand request, CancellationToken cancellationToken)
{
    var item = new Item
    {
        Name = request.Name,
        Value = request.Value
    };

    _itemRepository.Add(item);

    return Task.CompletedTask;
}

How critical is this issue for you? Will the above work for you in the meantime?

[jp-seini]

@afoxsonoco - an updated option to manually update the code, which keeps the body under Intent control (allowing the mapping to still be automated)

• Signature set to Mode.Ignore
• // IntentIgnore added above the return statement

[IntentManaged(Mode.Fully, Body = Mode.Fully, Signature = Mode.Ignore)]
public Task Handle(CreateItemCommand request, CancellationToken cancellationToken)
{
    var item = new Item
    {
        Name = request.Name,
        Value = request.Value
    };

    _itemRepository.Add(item);

    // IntentIgnore
    return Task.CompletedTask;
}

[afoxtrident]

Hi @jp-seini - absolutely not critical from us, but would be a good to have it in a future release. Thanks for confirming.