chore(examples): Add cancellation
example
#1477
Merged
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Motivation
There are some valid usecases for being notified of request cancellation and executing clean up logic on client cancellation.
This can be easily done with server streaming and bidi streaming, but there doesn't seem to be a straightforward approach for unary RPCs.
Solution
Creating a new task for unary requests (like in server/bidi streaming requests), having the unary request' future await on this new task with a CancellationToken drop guard.
Under the assumption that request futures are dropped when client cancels the request, this will notify the task through the drop guard's drop logic