Signal handling try micro#2: through the context

This approach expects the user to control their context to manage the service. A signal handler is installed by default by you can specify the option `SignalHandler()` to turn it off. The choice of keeping the signal handler in was intended to preserve backwards compatibility so that users of go-micro today were not surprised by the signal handling changes. Signed-off-by: Erik Hollensbe <github@hollensbe.org>
erikh · Nov 16, 2019 · 70633f1 · 70633f1
1 parent 383658e
commit 70633f1
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Showing 4 changed files with 25 additions and 8 deletions.
diff --git a/go.mod b/go.mod
@@ -35,6 +35,7 @@ require (
 	github.com/mitchellh/hashstructure v1.0.0
 	github.com/nats-io/nats.go v1.9.1
 	github.com/nlopes/slack v0.6.0
+	github.com/oxtoacart/bpool v0.0.0-20190530202638-03653db5a59c
 	github.com/pkg/errors v0.8.1
 	github.com/technoweenie/multipartstreamer v1.0.1 // indirect
 	go.uber.org/zap v1.12.0 // indirect

diff --git a/go.sum b/go.sum
@@ -283,6 +283,8 @@ github.com/opencontainers/runtime-tools v0.0.0-20181011054405-1d69bd0f9c39/go.mo
 github.com/openzipkin/zipkin-go v0.1.6/go.mod h1:QgAqvLzwWbR/WpD4A3cGpPtJrZXNIiJc5AZX7/PBEpw=
 github.com/oracle/oci-go-sdk v7.0.0+incompatible/go.mod h1:VQb79nF8Z2cwLkLS35ukwStZIg5F66tcBccjip/j888=
 github.com/ovh/go-ovh v0.0.0-20181109152953-ba5adb4cf014/go.mod h1:joRatxRJaZBsY3JAOEMcoOp05CnZzsx4scTxi95DHyQ=
+github.com/oxtoacart/bpool v0.0.0-20190530202638-03653db5a59c h1:rp5dCmg/yLR3mgFuSOe4oEnDDmGLROTvMragMUXpTQw=
+github.com/oxtoacart/bpool v0.0.0-20190530202638-03653db5a59c/go.mod h1:X07ZCGwUbLaax7L0S3Tw4hpejzu63ZrrQiUe6W0hcy0=
 github.com/pelletier/go-buffruneio v0.2.0/go.mod h1:JkE26KsDizTr40EUHkXVtNPvgGtbSNq5BcowyYOWdKo=
 github.com/pierrec/lz4 v2.0.5+incompatible/go.mod h1:pdkljMzZIN41W+lC3N2tnIh5sFi+IEE17M5jbnwPHcY=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=

diff --git a/options.go b/options.go
@@ -31,6 +31,8 @@ type Options struct {
 	// Other options for implementations of the interface
 	// can be stored in a context
 	Context context.Context
+
+	DisableSignalHandler bool
 }
 
 func newOptions(opts ...Option) Options {
@@ -81,6 +83,15 @@ func Context(ctx context.Context) Option {
 	}
 }
 
+// SignalHandler toggles automatic installation of the signal handler.
+// Users of this feature to disable the signal handler, should control liveness
+// of the service through the context.
+func SignalHandler(b bool) Option {
+	return func(o *Options) {
+		o.DisableSignalHandler = !b
+	}
+}
+
 func Server(s server.Server) Option {
 	return func(o *Options) {
 		o.Server = s

diff --git a/service.go b/service.go
@@ -168,14 +168,17 @@ func (s *service) Run() error {
 		return err
 	}
 
-	ch := make(chan os.Signal, 1)
-	signal.Notify(ch, syscall.SIGTERM, syscall.SIGINT, syscall.SIGQUIT)
-
-	select {
-	// wait on kill signal
-	case <-ch:
-	// wait on context cancel
-	case <-s.opts.Context.Done():
+	if s.opts.DisableSignalHandler {
+		<-s.opts.Context.Done()
+	} else {
+		ch := make(chan os.Signal, 1)
+		signal.Notify(ch, syscall.SIGTERM, syscall.SIGINT, syscall.SIGQUIT)
+		select {
+		// wait on kill signal
+		case <-ch:
+		// wait on context cancel
+		case <-s.opts.Context.Done():
+		}
 	}
 
 	return s.Stop()