udp input except no clean shutdown

src/device/input/input.go

@@ -3,6 +3,7 @@ package input
 import (
 	"context"
 	"os"
+	"strconv"
 	"syscall"
 )
 
@@ -47,6 +48,12 @@ func newSourceFunc() func() Input {
 			return singletonKeyboard
 		}
 	}
+	if port, _ := strconv.Atoi(os.Getenv("INPUT_UDP")); port != 0 {
+		singletonUDP := NewUDP(port)
+		return func() Input {
+			return singletonUDP
+		}
+	}
 	return func() Input {
 		generator := randomCharFromRange('a', 'g')
 		if p, ok := os.LookupEnv("INPUT_RANDOM_WEIGHT_FILE"); ok && len(p) > 0 {