Why do you encourage avoiding it? Afaik it's the only way to early-abort an operation since Goroutines operate in a cooperative, not preemptive, paradigm. To be very clear, I'm asking this completely in good faith looking to learn something new!
I'm not sure what you mean here. Preemptive/coorporative terminology refers to interrupting (not aborting) a CPU-bound task, in which case goroutines are fully preemptive on most platforms since Go 1.14, check the release notes for more info. However, this has nothing to do with context.
If you're referring to early-aborting IO operations, then yes, that's what context is for. However, this doesn't really have anything to do with goroutines, you could do the same if the runtime was built on OS threads.
This makes goroutines effectively cooperative still from the perspective of the developer. The preemptive runtime "just" prevents things like user code starving out the garbage collector. To interrupt a goroutine, your options are generally limited to context cancelation and closing the channel or socket being read, if any. And the goroutine may still refuse to exit (or whatever else you want it to do), though that's largely up to how you code it.
This difference is especially stark when compared with Erlang/BEAM where you can directly address, signal, and terminate its lightweight processes.
Another approach is special messages over a side channel.
Have a struct representing the set of associated activities, owning the channel.
But if you store your context in a struct (which is not the recommend “best practice” – but which you can do) it's no longer a function coloring issue.
I do that in on of my libraries and I feel that it's the right call (for that library).
An exception to the short-lived rule is to put context in your service struct and pass it as the base context when constructing the HTTP server, so that when you get a service shutdown signal, one can cancel requests gracefully.
But the API surface is huge, with 100s of methods on the connection and derived objects, with it being unclear which might block and be worthy of asynchronous cancellation. You never know when pulling an additional column if that one might be an overflow text/blob that does additional IO.
The solution, while not amazing is a method that you use like this:
old := conn.SetInterrupt(ctx)
defer conn.SetInterrupt(old)