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@matejb
Created May 20, 2017 12:21
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Golang context with cancellation on signal receive
func contextWithSigterm(ctx context.Context) context.Context {
ctxWithCancel, cancel := context.WithCancel(ctx)
go func() {
defer cancel()
signalCh := make(chan os.Signal, 1)
signal.Notify(signalCh, os.Interrupt, syscall.SIGTERM)
select {
case <-signalCh:
case <-ctx.Done():
}
}()
return ctxWithCancel
}
@bronger
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bronger commented Sep 25, 2022

Ah yes, thank you!

@stokito
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stokito commented Sep 27, 2023

You can use signal.NotifyContext() instead

@asafhad
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asafhad commented May 3, 2024

@stokito Exactly, here's an example taken from https://henvic.dev/posts/signal-notify-context/. Thanks @henvic!

// This example passes a context with a signal to tell a blocking function that
// it should abandon its work after an operating system signal is notified.
func main() {
	// Pass a context with a timeout to tell a blocking function that it
	// should abandon its work after the timeout elapses.
	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt)
	defer stop()

	select {
	case <-time.After(10 * time.Second):
		fmt.Println("missed signal")
	case <-ctx.Done():
		stop()
		fmt.Println("signal received")
	}
}

@henvic
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henvic commented May 3, 2024

You’re welcome!

LOL 😅

@stokito
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stokito commented May 31, 2024

@henvic could you please extend the example in your article?

The problem is that the os.Interrupt is an alias to syscall.SIGINT but at least on Linux we also must handle the SIGTERM:

ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)

I had a problem when the systemd service stuck during reloading.

@henvic
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henvic commented Jul 6, 2024

@stokito, thank you for the feedback. I've updated it.

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