request: add LocalIP (#1925)

* request: add LocalIP

Fix TODO that was added: Add LocalIP and test the Clear() method.
Signed-off-by: Miek Gieben <miek@miek.nl>

* Move to Errorf

PR feedback and move to Errorf instead Fatalf.
Signed-off-by: Miek Gieben <miek@miek.nl>

request/request.go

@@ -32,7 +32,7 @@ type Request struct {
 	port      string // client's port.
 	family    int    // transport's family.
 	localPort string // server's port.
-	// TODO(miek): localIP once that is merged.
+	localIP   string // server's ip.
 }
 
 // NewWithQuestion returns a new request based on the old, but with a new question
@@ -61,11 +61,18 @@ func (r *Request) IP() string {
 
 // LocalIP gets the (local) IP address of server handling the request.
 func (r *Request) LocalIP() string {
+	if r.localIP != "" {
+		return r.localIP
+	}
+
 	ip, _, err := net.SplitHostPort(r.W.LocalAddr().String())
 	if err != nil {
-		return r.W.LocalAddr().String()
+		r.localIP = r.W.LocalAddr().String()
+		return r.localIP
 	}
-	return ip
+
+	r.localIP = ip
+	return r.localIP
 }
 
 // Port gets the (remote) port of the client making the request.
@@ -423,6 +430,7 @@ func (r *Request) ErrorMessage(rcode int) *dns.Msg {
 func (r *Request) Clear() {
 	r.name = ""
 	r.ip = ""
+	r.localIP = ""
 	r.port = ""
 	r.localPort = ""
 	r.family = 0

request/request_test.go

@@ -14,21 +14,21 @@ func TestRequestDo(t *testing.T) {
 
 	st.Do()
 	if st.do == nil {
-		t.Fatalf("Expected st.do to be set")
+		t.Errorf("Expected st.do to be set")
 	}
 }
 
 func TestRequestRemote(t *testing.T) {
 	st := testRequest()
 	if st.IP() != "10.240.0.1" {
-		t.Fatalf("Wrong IP from request")
+		t.Errorf("Wrong IP from request")
 	}
 	p := st.Port()
 	if p == "" {
-		t.Fatalf("Failed to get Port from request")
+		t.Errorf("Failed to get Port from request")
 	}
 	if p != "40212" {
-		t.Fatalf("Wrong port from request")
+		t.Errorf("Wrong port from request")
 	}
 }
 
@@ -202,3 +202,22 @@ func testRequest() Request {
 	m.SetEdns0(4097, true)
 	return Request{W: &test.ResponseWriter{}, Req: m}
 }
+
+func TestRequestClear(t *testing.T) {
+	st := testRequest()
+	if st.IP() != "10.240.0.1" {
+		t.Errorf("Wrong IP from request")
+	}
+	p := st.Port()
+	if p == "" {
+		t.Errorf("Failed to get Port from request")
+	}
+	st.Clear()
+	if st.ip != "" {
+		t.Errorf("Expected st.ip to be cleared after Clear")
+	}
+
+	if st.port != "" {
+		t.Errorf("Expected st.port to be cleared after Clear")
+	}
+}