async interceptors are blocking the chain about pedestal HOT 4 CLOSED

This is expected behavior. Interceptors always execute in order, and the contract of an Interceptor is that it takes and returns a Context. Async interceptors are migrated off of the HTTP request handling thread-pool to an async-pool until they are complete. That is, they complete asynchronously with respect to the request pool. This notion of async handling comes from the Servlet spec and matches the pattern seen in most Java Web Handlers (eg: Jetty).

You can dispatch other Futures/threads on other thread-pools and store their handles within the Context to achieve a non-blocking interceptor. If you do this, you will first want to "go async" since eventually an interceptor will await the results of dispatch.

I hope this helps clarify things

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@ohpauleez that makes sense now, thanks a lot!
But to be honest it is easy to get confused. Do you think a slight improvement for async interceptor docs makes sense?

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I'm always happy to help and I'm glad that all made sense!
Updates to the docs and additional clarification is always helpful for the project and the community. It's one of the best ways to contribute and help improve the project.

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I've made documentation improvements to more explicitly describe what async behavior is about, and the pitfalls therein.

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