fix golint issues in rest (#529)

rest/handler/authhandler.go

@@ -28,15 +28,19 @@ var (
 )
 
 type (
+	// A AuthorizeOptions is authorize options.
 	AuthorizeOptions struct {
 		PrevSecret string
 		Callback   UnauthorizedCallback
 	}
 
+	// UnauthorizedCallback defines the method of unauthorized callback.
 	UnauthorizedCallback func(w http.ResponseWriter, r *http.Request, err error)
-	AuthorizeOption      func(opts *AuthorizeOptions)
+	// AuthorizeOption defines the method to customize an AuthorizeOptions.
+	AuthorizeOption func(opts *AuthorizeOptions)
 )
 
+// Authorize returns an authorize middleware.
 func Authorize(secret string, opts ...AuthorizeOption) func(http.Handler) http.Handler {
 	var authOpts AuthorizeOptions
 	for _, opt := range opts {
@@ -78,12 +82,14 @@ func Authorize(secret string, opts ...AuthorizeOption) func(http.Handler) http.H
 	}
 }
 
+// WithPrevSecret returns an AuthorizeOption with setting previous secret.
 func WithPrevSecret(secret string) AuthorizeOption {
 	return func(opts *AuthorizeOptions) {
 		opts.PrevSecret = secret
 	}
 }
 
+// WithUnauthorizedCallback returns an AuthorizeOption with setting unauthorized callback.
 func WithUnauthorizedCallback(callback UnauthorizedCallback) AuthorizeOption {
 	return func(opts *AuthorizeOptions) {
 		opts.Callback = callback