First working version

errors.go

@@ -0,0 +1,53 @@
+package main
+
+// RejectOption represents an option used to control the way connection is
+// rejected.
+type RejectOption func(*rejectConnectionError)
+
+// RejectionReason returns an option that makes connection to be rejected with
+// given reason.
+func RejectionReason(reason string) RejectOption {
+	return func(err *rejectConnectionError) {
+		err.reason = reason
+	}
+}
+
+// RejectionStatus returns an option that makes connection to be rejected with
+// given HTTP status code.
+func RejectionStatus(code int) RejectOption {
+	return func(err *rejectConnectionError) {
+		err.code = code
+	}
+}
+
+// RejectionHeader returns an option that makes connection to be rejected with
+// given HTTP headers.
+func RejectionHeader(h HandshakeHeader) RejectOption {
+	return func(err *rejectConnectionError) {
+		err.header = h
+	}
+}
+// RejectConnectionError constructs an error that could be used to control the way
+// handshake is rejected by Upgrader.
+func RejectConnectionError(options ...RejectOption) error {
+	err := new(rejectConnectionError)
+	for _, opt := range options {
+		opt(err)
+	}
+	return err
+}
+
+// rejectConnectionError represents a rejection of upgrade error.
+//
+// It can be returned by Upgrader's On* hooks to control the way WebSocket
+// handshake is rejected.
+type rejectConnectionError struct {
+	reason string
+	code   int
+	header HandshakeHeader
+}
+
+// Error implements error interface.
+func (r *rejectConnectionError) Error() string {
+	return r.reason
+}