simplify various code using new map index rule

R=r
CC=golang-dev
http://codereview.appspot.com/833044

3 files changed, 28 insertions, 76 deletions

diff --git a/src/pkg/websocket/client.go b/src/pkg/websocket/client.go
index 52870800c..90597a821 100644
--- a/src/pkg/websocket/client.go
+++ b/src/pkg/websocket/client.go
@@ -25,14 +25,10 @@ type ProtocolError struct {
 
 var (
 	ErrBadStatus            = &ProtocolError{"bad status"}
-	ErrNoUpgrade            = &ProtocolError{"no upgrade"}
-	ErrBadUpgrade           = &ProtocolError{"bad upgrade"}
-	ErrNoWebSocketOrigin    = &ProtocolError{"no WebSocket-Origin"}
-	ErrBadWebSocketOrigin   = &ProtocolError{"bad WebSocket-Origin"}
-	ErrNoWebSocketLocation  = &ProtocolError{"no WebSocket-Location"}
-	ErrBadWebSocketLocation = &ProtocolError{"bad WebSocket-Location"}
-	ErrNoWebSocketProtocol  = &ProtocolError{"no WebSocket-Protocol"}
-	ErrBadWebSocketProtocol = &ProtocolError{"bad WebSocket-Protocol"}
+	ErrBadUpgrade           = &ProtocolError{"missing or bad upgrade"}
+	ErrBadWebSocketOrigin   = &ProtocolError{"missing or bad WebSocket-Origin"}
+	ErrBadWebSocketLocation = &ProtocolError{"missing or bad WebSocket-Location"}
+	ErrBadWebSocketProtocol = &ProtocolError{"missing or bad WebSocket-Protocol"}
 	ErrChallengeResponse    = &ProtocolError{"mismatch challange/response"}
 	secKeyRandomChars       [0x30 - 0x21 + 0x7F - 0x3A]byte
 )
@@ -244,40 +240,21 @@ func handshake(resourceName, host, origin, location, protocol string, br *bufio.
 	}
 
 	// Step 41. check websocket headers.
-	upgrade, found := resp.Header["Upgrade"]
-	if !found {
-		return ErrNoUpgrade
-	}
-	if upgrade != "WebSocket" {
-		return ErrBadUpgrade
-	}
-	connection, found := resp.Header["Connection"]
-	if !found || strings.ToLower(connection) != "upgrade" {
+	if resp.Header["Upgrade"] != "WebSocket" ||
+		strings.ToLower(resp.Header["Connection"]) != "upgrade" {
 		return ErrBadUpgrade
 	}
 
-	s, found := resp.Header["Sec-Websocket-Origin"]
-	if !found {
-		return ErrNoWebSocketOrigin
-	}
-	if s != origin {
+	if resp.Header["Sec-Websocket-Origin"] != origin {
 		return ErrBadWebSocketOrigin
 	}
-	s, found = resp.Header["Sec-Websocket-Location"]
-	if !found {
-		return ErrNoWebSocketLocation
-	}
-	if s != location {
+
+	if resp.Header["Sec-Websocket-Location"] != location {
 		return ErrBadWebSocketLocation
 	}
-	if protocol != "" {
-		s, found = resp.Header["Sec-Websocket-Protocol"]
-		if !found {
-			return ErrNoWebSocketProtocol
-		}
-		if s != protocol {
-			return ErrBadWebSocketProtocol
-		}
+
+	if protocol != "" && resp.Header["Sec-Websocket-Protocol"] != protocol {
+		return ErrBadWebSocketProtocol
 	}
 
 	// Step 42-43. get expected data from challange data.
@@ -322,40 +299,18 @@ func draft75handshake(resourceName, host, origin, location, protocol string, br
 	if resp.Status != "101 Web Socket Protocol Handshake" {
 		return ErrBadStatus
 	}
-	upgrade, found := resp.Header["Upgrade"]
-	if !found {
-		return ErrNoUpgrade
-	}
-	if upgrade != "WebSocket" {
-		return ErrBadUpgrade
-	}
-	connection, found := resp.Header["Connection"]
-	if !found || connection != "Upgrade" {
+	if resp.Header["Upgrade"] != "WebSocket" ||
+		resp.Header["Connection"] != "Upgrade" {
 		return ErrBadUpgrade
 	}
-
-	ws_origin, found := resp.Header["Websocket-Origin"]
-	if !found {
-		return ErrNoWebSocketOrigin
-	}
-	if ws_origin != origin {
+	if resp.Header["Websocket-Origin"] != origin {
 		return ErrBadWebSocketOrigin
 	}
-	ws_location, found := resp.Header["Websocket-Location"]
-	if !found {
-		return ErrNoWebSocketLocation
-	}
-	if ws_location != location {
+	if resp.Header["Websocket-Location"] != location {
 		return ErrBadWebSocketLocation
 	}
-	if protocol != "" {
-		ws_protocol, found := resp.Header["Websocket-Protocol"]
-		if !found {
-			return ErrNoWebSocketProtocol
-		}
-		if ws_protocol != protocol {
-			return ErrBadWebSocketProtocol
-		}
+	if protocol != "" && resp.Header["Websocket-Protocol"] != protocol {
+		return ErrBadWebSocketProtocol
 	}
 	return
 }
diff --git a/src/pkg/websocket/server.go b/src/pkg/websocket/server.go
index cc1ff9385..7faf6ba49 100644
--- a/src/pkg/websocket/server.go
+++ b/src/pkg/websocket/server.go
@@ -75,14 +75,11 @@ func (f Handler) ServeHTTP(c *http.Conn, req *http.Request) {
 	}
 	// HTTP version can be safely ignored.
 
-	if v, found := req.Header["Upgrade"]; !found ||
-		strings.ToLower(v) != "websocket" {
-		return
-	}
-	if v, found := req.Header["Connection"]; !found ||
-		strings.ToLower(v) != "upgrade" {
+	if strings.ToLower(req.Header["Upgrade"]) != "websocket" ||
+		strings.ToLower(req.Header["Connection"]) != "upgrade" {
 		return
 	}
+
 	// TODO(ukai): check Host
 	origin, found := req.Header["Origin"]
 	if !found {
@@ -181,12 +178,12 @@ func (f Draft75Handler) ServeHTTP(c *http.Conn, req *http.Request) {
 		io.WriteString(c, "Unexpected request")
 		return
 	}
-	if v, found := req.Header["Upgrade"]; !found || v != "WebSocket" {
+	if req.Header["Upgrade"] != "WebSocket" {
 		c.WriteHeader(http.StatusBadRequest)
 		io.WriteString(c, "missing Upgrade: WebSocket header")
 		return
 	}
-	if v, found := req.Header["Connection"]; !found || v != "Upgrade" {
+	if req.Header["Connection"] != "Upgrade" {
 		c.WriteHeader(http.StatusBadRequest)
 		io.WriteString(c, "missing Connection: Upgrade header")
 		return
diff --git a/src/pkg/websocket/websocket_test.go b/src/pkg/websocket/websocket_test.go
index 58065580e..0762fca69 100644
--- a/src/pkg/websocket/websocket_test.go
+++ b/src/pkg/websocket/websocket_test.go
@@ -42,18 +42,18 @@ func TestEcho(t *testing.T) {
 	ws, err := newClient("/echo", "localhost", "http://localhost",
 		"ws://localhost/echo", "", client, handshake)
 	if err != nil {
-		t.Errorf("WebSocket handshake error", err)
+		t.Errorf("WebSocket handshake error: %v", err)
 		return
 	}
 
 	msg := []byte("hello, world\n")
 	if _, err := ws.Write(msg); err != nil {
-		t.Errorf("Write: error %v", err)
+		t.Errorf("Write: %v", err)
 	}
 	var actual_msg = make([]byte, 512)
 	n, err := ws.Read(actual_msg)
 	if err != nil {
-		t.Errorf("Read: error %v", err)
+		t.Errorf("Read: %v", err)
 	}
 	actual_msg = actual_msg[0:n]
 	if !bytes.Equal(msg, actual_msg) {
@@ -73,7 +73,7 @@ func TestEchoDraft75(t *testing.T) {
 	ws, err := newClient("/echoDraft75", "localhost", "http://localhost",
 		"ws://localhost/echoDraft75", "", client, draft75handshake)
 	if err != nil {
-		t.Errorf("WebSocket handshake error", err)
+		t.Errorf("WebSocket handshake: %v", err)
 		return
 	}
 
@@ -104,7 +104,7 @@ func TestWithQuery(t *testing.T) {
 	ws, err := newClient("/echo?q=v", "localhost", "http://localhost",
 		"ws://localhost/echo?q=v", "", client, handshake)
 	if err != nil {
-		t.Errorf("WebSocket handshake error", err)
+		t.Errorf("WebSocket handshake: %v", err)
 		return
 	}
 	ws.Close()