improve code quality (#2128)

* Fix inefficient string comparison

* Fix unnecessary calls to Printf

* Canonicalize header key

* Replace `t.Sub(time.Now())` with `time.Until`

* Remove unnecessary blank (_) identifier

* Remove unnecessary use of slice

* Remove unnecessary comparison with bool

api/handler/rpc/rpc.go

@@ -122,7 +122,7 @@ func (h *rpcHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	md["Host"] = r.Host
 	md["Method"] = r.Method
 	// get canonical headers
-	for k, _ := range r.Header {
+	for k := range r.Header {
 		// may be need to get all values for key like r.Header.Values() provide in go 1.14
 		md[textproto.CanonicalMIMEHeaderKey(k)] = r.Header.Get(k)
 	}

api/handler/rpc/stream.go

@@ -38,7 +38,7 @@ func serveWebsocket(ctx context.Context, w http.ResponseWriter, r *http.Request,
 	}
 
 	hdr := make(http.Header)
-	if proto, ok := r.Header["Sec-WebSocket-Protocol"]; ok {
+	if proto, ok := r.Header["Sec-Websocket-Protocol"]; ok {
 		for _, p := range proto {
 			switch p {
 			case "binary":

auth/rules.go

@@ -83,7 +83,7 @@ func Verify(rules []*Rule, acc *Account, res *Resource) error {
 // not case sensitive.
 func include(slice []string, val string) bool {
 	for _, s := range slice {
-		if strings.ToLower(s) == strings.ToLower(val) {
+		if strings.EqualFold(s, val) {
 			return true
 		}
 	}

client/rpc_client.go

@@ -379,7 +379,7 @@ func (r *rpcClient) Call(ctx context.Context, request Request, response interfac
 	} else {
 		// got a deadline so no need to setup context
 		// but we need to set the timeout we pass along
-		opt := WithRequestTimeout(d.Sub(time.Now()))
+		opt := WithRequestTimeout(time.Until(d))
 		opt(&callOpts)
 	}
 

codec/grpc/util.go

@@ -15,7 +15,7 @@ func decode(r io.Reader) (uint8, []byte, error) {
 	header := make([]byte, 5)
 
 	// read the header
-	if _, err := r.Read(header[:]); err != nil {
+	if _, err := r.Read(header); err != nil {
 		return uint8(0), nil, err
 	}
 
@@ -60,7 +60,7 @@ func encode(cf uint8, buf []byte, w io.Writer) error {
 	binary.BigEndian.PutUint32(header[1:], uint32(len(buf)))
 
 	// read the header
-	if _, err := w.Write(header[:]); err != nil {
+	if _, err := w.Write(header); err != nil {
 		return err
 	}
 

config/default_test.go

@@ -158,7 +158,7 @@ func TestConfigWatcherDirtyOverrite(t *testing.T) {
 	}
 	runtime.Gosched()
 
-	for i, _ := range ss {
+	for i := range ss {
 		k := fmt.Sprintf("key%d", i)
 		v := fmt.Sprintf("val%d", i)
 		equalS(t, conf.Get(k).String(""), v)

config/source/file/watcher_linux.go

@@ -41,7 +41,7 @@ func (w *watcher) Next() (*source.ChangeSet, error) {
 
 	// try get the event
 	select {
-	case event, _ := <-w.fw.Events:
+	case event := <-w.fw.Events:
 		if event.Op == fsnotify.Rename {
 			// check existence of file, and add watch again
 			_, err := os.Stat(event.Name)

runtime/kubernetes/logs.go

@@ -115,7 +115,7 @@ func (k *klog) Read() ([]runtime.LogRecord, error) {
 			logParams["tailLines"] = strconv.Itoa(int(k.options.Count))
 		}
 
-		if k.options.Stream == true {
+		if k.options.Stream {
 			logParams["follow"] = "true"
 		}
 

util/qson/qson_test.go

@@ -52,7 +52,7 @@ func ExampleToJSON() {
 	if err != nil {
 		panic(err)
 	}
-	fmt.Printf(string(b))
+	fmt.Print(string(b))
 	// Output: {"a":"xyz","b":{"c":456}}
 }