Add command line tool

app/shaker/shaker.go

@@ -0,0 +1,50 @@
+package main
+
+import (
+	"flag"
+	"log"
+	"net"
+	"time"
+
+	"github.com/tevino/tcp-shaker"
+)
+
+func parseFlag() (addr string, timeout time.Duration) {
+	var timeoutMS int
+	// Flag definition
+	flag.IntVar(&timeoutMS, "timeout", 1000, "Timeout for the whole process(domain resolving is included)")
+	flag.StringVar(&addr, "addr", "google.com:80", "TCP address to test")
+	// Parse flags
+	flag.Parse()
+	if _, err := net.ResolveTCPAddr("tcp", addr); err != nil {
+		log.Fatalf("Can not resolve '%s': %s", addr, err)
+	}
+	timeout = time.Duration(timeoutMS) * time.Millisecond
+	return
+}
+
+func main() {
+	// Parse flag
+	addr, timeout := parseFlag()
+	log.Printf("Checking %s with timeout %s", addr, timeout)
+	// Init shaker
+	s := tcp.Shaker{}
+	if err := s.Init(); err != nil {
+		log.Fatal("Initializing failed:", err)
+	}
+	// Test addr
+	err := s.Test(addr, timeout)
+	// Print error
+	switch err {
+	case tcp.ErrTimeout:
+		log.Fatalf("Connect to '%s' timed out", addr)
+	case nil:
+		log.Printf("Connect to '%s' succeeded", addr)
+	default:
+		if e, ok := err.(*tcp.ErrConnect); ok {
+			log.Fatalf("Connect to '%s' failed: %s", addr, e)
+		} else {
+			log.Fatalf("Error occurred while connecting to '%s': %s", addr, err)
+		}
+	}
+}