refactor simple TCP server into pkg

cmd/primetime/main.go

@@ -0,0 +1,23 @@
+package main
+
+import (
+	"log"
+	"net"
+
+	"protohackers/pkg/conn"
+)
+
+type data struct {
+	Method string `json:"method"`
+	Number int    `json:"number"`
+}
+
+func main() {
+	err := conn.StartSimple(primetime)
+	if err != nil {
+		log.Fatalln(err)
+	}
+}
+
+func primetime(c net.Conn) {
+}

cmd/smoketest/main.go

@@ -1,40 +1,22 @@
 package main
 
 import (
-	"fmt"
 	"io"
 	"log"
 	"net"
-	"os"
-)
 
-const (
-	connPort = "3030"
-	connType = "tcp4"
+	"protohackers/pkg/conn"
 )
 
 func main() {
-	l, err := net.Listen(connType, ":"+connPort)
-	if err != nil {
-		log.Fatalln(err)
-		os.Exit(1)
-	}
-	defer l.Close()
-
-	fmt.Println(fmt.Sprintf("Listening on port %s", connPort))
-
-	for {
-		conn, err := l.Accept()
+	err := conn.StartSimple(smoketest)
 	if err != nil {
 		log.Fatalln(err)
 	}
-		go handleRequest(conn)
-	}
 }
 
-func handleRequest(conn net.Conn) {
-	defer conn.Close()
-	if _, err := io.Copy(conn, conn); err != nil {
+func smoketest(c net.Conn) {
+	if _, err := io.Copy(c, c); err != nil {
 		log.Fatalln(err)
 	}
 }

pkg/conn/conn.go

@@ -0,0 +1,33 @@
+package conn
+
+import (
+	"fmt"
+	"net"
+)
+
+const (
+	Port = ":3030"
+	Type = "tcp4"
+)
+
+func StartSimple(handler func(conn net.Conn)) error {
+	l, err := net.Listen(Type, Port)
+	if err != nil {
+		return err
+	}
+	defer l.Close()
+
+	fmt.Println(fmt.Sprintf("Listening on port %s", Port))
+
+	for {
+		c, err := l.Accept()
+		if err != nil {
+			return err
+		}
+		go handler(c)
+		err = c.Close()
+		if err != nil {
+			return err
+		}
+	}
+}