feat(protocols): refactor protocol utilities into centralized protocols module

ts/protocols/websocket/constants.ts

@@ -0,0 +1,60 @@
+/**
+ * WebSocket Protocol Constants
+ * Based on RFC 6455
+ */
+
+/**
+ * WebSocket opcode types
+ */
+export enum WebSocketOpcode {
+  CONTINUATION = 0x0,
+  TEXT = 0x1,
+  BINARY = 0x2,
+  CLOSE = 0x8,
+  PING = 0x9,
+  PONG = 0xa,
+}
+
+/**
+ * WebSocket close codes
+ */
+export enum WebSocketCloseCode {
+  NORMAL_CLOSURE = 1000,
+  GOING_AWAY = 1001,
+  PROTOCOL_ERROR = 1002,
+  UNSUPPORTED_DATA = 1003,
+  NO_STATUS_RECEIVED = 1005,
+  ABNORMAL_CLOSURE = 1006,
+  INVALID_FRAME_PAYLOAD_DATA = 1007,
+  POLICY_VIOLATION = 1008,
+  MESSAGE_TOO_BIG = 1009,
+  MISSING_EXTENSION = 1010,
+  INTERNAL_ERROR = 1011,
+  SERVICE_RESTART = 1012,
+  TRY_AGAIN_LATER = 1013,
+  BAD_GATEWAY = 1014,
+  TLS_HANDSHAKE = 1015,
+}
+
+/**
+ * WebSocket protocol version
+ */
+export const WEBSOCKET_VERSION = 13;
+
+/**
+ * WebSocket magic string for handshake
+ */
+export const WEBSOCKET_MAGIC_STRING = '258EAFA5-E914-47DA-95CA-C5AB0DC85B11';
+
+/**
+ * WebSocket headers
+ */
+export const WEBSOCKET_HEADERS = {
+  UPGRADE: 'upgrade',
+  CONNECTION: 'connection',
+  SEC_WEBSOCKET_KEY: 'sec-websocket-key',
+  SEC_WEBSOCKET_VERSION: 'sec-websocket-version',
+  SEC_WEBSOCKET_ACCEPT: 'sec-websocket-accept',
+  SEC_WEBSOCKET_PROTOCOL: 'sec-websocket-protocol',
+  SEC_WEBSOCKET_EXTENSIONS: 'sec-websocket-extensions',
+} as const;