Async flow control

[danielmarbach]

Proposed Changes

Addresses #1644

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[danielmarbach]

@stebet @bollhals @paulomorgado would appreciate a look since this is some non trivial magic.

[lukebakken]

Thank you @danielmarbach

[lukebakken]

Should we worry about the scenario where flow control is active and a publisher just keeps on going? I'm assuming this will "pile up" tasks/continuations/"under the hood magic" behind the scenes. Should there be a limit to the number of publishes that can happen while blocked by flow control?

[danielmarbach]

Should we worry about the scenario where flow control is active and a publisher just keeps on going? I'm assuming this will "pile up" tasks/continuations/"under the hood magic" behind the scenes. Should there be a limit to the number of publishes that can happen while blocked by flow control?

Assuming this is actually a problem that requires to be solved isn't this already an issue before this change?

[danielmarbach]

With these changes in we will have also the door open to implement IAsyncDisposable across both TFMs.

[lukebakken]

Assuming this is actually a problem that requires to be solved isn't this already an issue before this change?

Ah, ok, this will only be a problem if someone is not immediately await-ing the BasicPublishAsync result, and batching them up. I guess it's on the user in that case 😉

[danielmarbach]

Having here in the PR is more then enough especially considering the implementation I provided is significantly different due to modernizations applied