Adding example files from ch3

network_programming/tcp/ch3/dail_test.go

@@ -0,0 +1,66 @@
+package ch3
+
+import (
+	"io"
+	"net"
+	"testing"
+)
+
+func TestDial(t *testing.T) {
+	//create a listener on a random port to make out test connection to
+	listener, err := net.Listen("tcp", "127.0.0.1:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// channel that receives struct objects
+	done := make(chan struct{})
+
+	// Goroutine (aka handler) for listening for connections
+	go func() {
+		defer func() { done <- struct{}{} }()
+
+		for {
+			conn, err := listener.Accept()
+			if err != nil {
+				t.Log(err)
+				return
+			}
+			// goroutine for responding to connection requests
+			go func(c net.Conn) {
+				defer func() {
+					c.Close()
+					done <- struct{}{}
+				}()
+
+				// create a slice of size 1024 (1 kilobyte)
+				buf := make([]byte, 1024)
+				for {
+					// reads up to 1024 bytes at a time from the socket
+					n, err := c.Read(buf)
+					if err != nil {
+						// c.Read returns io.EOF when FIN packet (graceful termination) is received
+						if err != io.EOF {
+							t.Error(err)
+						}
+						return
+					}
+					// logs the bytes it receives
+					t.Logf("received: %q", buf[:n])
+				}
+			}(conn)
+
+		}
+	}()
+
+	// Now we make our client
+	conn, err := net.Dial("tcp", listener.Addr().String())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	conn.Close()
+	<-done
+	listener.Close()
+	<-done
+}

network_programming/tcp/ch3/listen_test.go

@@ -0,0 +1,31 @@
+package ch3
+
+import (
+	"net"
+	"testing"
+)
+
+func TestListener(t *testing.T) {
+	listener, err := net.Listen("tcp", "0.0.0.0:0")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	defer func() { _ = listener.Close() }()
+
+	t.Logf("bound to port %q", listener.Addr())
+
+	// example for handling connections and processing connections in a goroutine
+	// for {
+	// 	conn, err := listener.Accept()
+	// 	if err != nil {
+	// 		t.Fatal(err)
+	// 	}
+
+	// 	go func(c net.Conn) {
+	// 		defer c.Close()
+	// 		// Your code goes here to handle the connection
+	// 	}(conn)
+	// }
+
+}