Also catch SIGTERM on default settings.

This is useful with services like AWS Fargate where SIGTERM is sent when
container is being stopped [1]. Can drastically speed up the shutdown
and most importantly does it gracefully.

Caveats: won't work on Windows.

[1] https://aws.amazon.com/blogs/containers/graceful-shutdowns-with-ecs/

Signed-off-by: Ville Valkonen <[email protected]>

Author: weezel

sigmod/signal.go

@@ -4,6 +4,7 @@ package sigmod
 import (
 	"os"
 	"os/signal"
+	"syscall"
 )
 
 const ID = "sigmod"
@@ -14,10 +15,13 @@ type Listener struct {
 }
 
 // New creates signal listener for given signals.
-// If no signal is provided, os.Interrupt will be used.
+// If no signal is provided, os.Interrupt and SIGTERM will be used.
 func New(signals ...os.Signal) *Listener {
 	if len(signals) == 0 {
-		signals = []os.Signal{os.Interrupt}
+		signals = []os.Signal{
+			os.Interrupt,
+			syscall.SIGTERM, // XXX Not available on Windows
+		}
 	}
 	return &Listener{
 		sigs: signals,

sigmod/signal_test.go

@@ -2,6 +2,7 @@ package sigmod_test
 
 import (
 	"os"
+	"runtime"
 	"syscall"
 	"testing"
 
@@ -12,23 +13,34 @@ import (
 
 func TestListener(t *testing.T) {
 	tests := []struct {
-		name    string
-		signals []os.Signal
+		name     string
+		signals  []os.Signal
+		inputSig syscall.Signal
 	}{
 		{
-			name:    "Defaults",
-			signals: []os.Signal{},
+			name:     "Defaults",
+			signals:  []os.Signal{},
+			inputSig: syscall.SIGINT,
 		},
 		{
-			name:    "Interrupt",
-			signals: []os.Signal{os.Interrupt},
+			name:     "Interrupt",
+			signals:  []os.Signal{os.Interrupt},
+			inputSig: syscall.SIGINT,
+		},
+		{
+			name:     "SIGTERM",
+			signals:  []os.Signal{syscall.SIGTERM},
+			inputSig: syscall.SIGTERM,
 		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
 			l := sigmod.New(tt.signals...)
 			require.NoError(t, l.Init())
-			require.NoError(t, syscall.Kill(syscall.Getpid(), syscall.SIGINT))
+			if tt.inputSig == syscall.SIGTERM && runtime.GOOS == "windows" {
+				t.Skip("Windows doesn't support SIGTERM")
+			}
+			require.NoError(t, syscall.Kill(syscall.Getpid(), tt.inputSig))
 			require.NoError(t, l.Run())
 			require.NoError(t, l.Stop())
 			require.Equal(t, "sigmod", l.ID())