bare-ws

stable

bare-ws — WebSocket library for JavaScript.

npm i bare-ws

Usage

const ws = require('bare-ws')

const server = new ws.Server({ port: 8080 }, (socket) => {
  socket.on('data', (data) => {
    console.log(data.toString())
  })
})

server.on('listening', () => {
  const socket = new ws.Socket({ port: 8080 })

  socket.write('Hello WebSocket')
})

API

Socket

`new Socket(opts: WebSocketOptions)`

Open a WebSocket connection to url, or wrap an already-connected opts.socket when acting as the server side of a handshake.

Overloads:

new Socket(opts: WebSocketOptions)
new Socket(url: URL | string, opts?: WebSocketOptions)

Parameters

Parameter	Type	Default	Description
`opts`	`WebSocketOptions`	—	Connection options: `host`/`hostname`, `port`, `path`, `secure`, or an already-connected `socket` to wrap.

`_destroy(err: Error | null, cb: StreamCallback): void`

Parameters

Parameter	Type	Default	Description
`err`	`Error` \| `null`	—	—
`cb`	`StreamCallback`	—	—

`_final(cb: StreamCallback): void`

Parameters

Parameter	Type	Default	Description
`cb`	`StreamCallback`	—	—

`_open(cb: StreamCallback): void`

Parameters

Parameter	Type	Default	Description
`cb`	`StreamCallback`	—	—

`_read(size: number): void`

Parameters

Parameter	Type	Default	Description
`size`	`number`	—	—

`_write(data: unknown, encoding: StreamEncoding, cb: StreamCallback): void`

Parameters

Parameter	Type	Default	Description
`data`	`unknown`	—	—
`encoding`	`StreamEncoding`	—	—
`cb`	`StreamCallback`	—	—

`_writev(batch: { chunk: unknown; encoding: StreamEncoding }[], cb: StreamCallback): void`

Parameters

Parameter	Type	Default	Description
`batch`	`{ chunk: unknown; encoding: StreamEncoding }[]`	—	—
`cb`	`StreamCallback`	—	—

`close(code?: number, reason?: string | Buffer): void`

Start the closing handshake with a status and optional reason. The status must be valid to send in a close frame, and the UTF-8 encoded reason must be at most 123 bytes. Defaults to status 1000 with an empty reason.

Parameters

Parameter	Type	Default	Description
`code?`	`number`	—	The close status sent to the peer.
`reason?`	`string` \| `Buffer`	—	A human-readable reason, as text or bytes, sent after the status.

Throws

RangeError — code is not a valid close status, or reason is longer than 123 bytes once encoded as UTF-8.

`closeCode: number`

The status the peer closed with, once it has sent a close frame. 1005 if the close frame carried no status, and 1006 until one arrives at all, so a connection that went away without closing keeps it. Readable from a close listener.

`closed: boolean`

`closeReason: Buffer`

The reason the peer closed with, empty unless its close frame carried one past the status. Readable from a close listener.

`cork(): void`

`destroy(err?: Error | null): void`

Parameters

Parameter	Type	Default	Description
`err?`	`Error` \| `null`	—	—

`destroyed: boolean`

`destroying: boolean`

`end(cb?: StreamCallback): this`

Overloads:

end(cb?: StreamCallback): this
end(data: unknown, encoding?: BufferEncoding, cb?: StreamCallback): this
end(data: unknown, cb?: StreamCallback): this

Parameters

Parameter	Type	Default	Description
`cb?`	`StreamCallback`	—	—

`errored: Error | null`

`pause(): this`

`ping(data?: string | Buffer): void`

Send a ping frame to the peer.

Parameters

Parameter	Type	Default	Description
`data?`	`string` \| `Buffer`	—	The payload of the ping frame; a string is converted to a `Buffer`.

Throws

NOT_CONNECTED — the socket has not finished connecting, has closed, or has been ended, since nothing may follow the close frame that ending sends.
INVALID_CONTROL_PAYLOAD_LENGTH — data is longer than 125 bytes.
TypeError — data is neither a string nor a view of bytes.

`pipe<S extends Writable>(dest: S, cb?: StreamCallback): S`

Parameters

Parameter	Type	Default	Description
`dest`	`S`	—	—
`cb?`	`StreamCallback`	—	—

`pong(data?: string | Buffer): void`

Send a pong frame to the peer.

Parameters

Parameter	Type	Default	Description
`data?`	`string` \| `Buffer`	—	The payload of the pong frame; a string is converted to a `Buffer`.

Throws

NOT_CONNECTED — the socket has not finished connecting, has closed, or has been ended, since nothing may follow the close frame that ending sends.
INVALID_CONTROL_PAYLOAD_LENGTH — data is longer than 125 bytes.
TypeError — data is neither a string nor a view of bytes.

`protocol: string | null`

The subprotocol selected by the server. null before the client connection opens and when the handshake selects no subprotocol.

`push(data: unknown | null, encoding?: BufferEncoding): boolean`

Parameters

Parameter	Type	Default	Description
`data`	`unknown` \| `null`	—	—
`encoding?`	`BufferEncoding`	—	—

`read(): unknown | null`

`readable: boolean`

`resume(): this`

`setEncoding(encoding: BufferEncoding): void`

Parameters

Parameter	Type	Default	Description
`encoding`	`BufferEncoding`	—	—

`Socket.handshake(req: HTTPClientRequest, cb: (error: WebSocketError | null) => void): void`

Perform the client side of the WebSocket opening handshake over req, calling cb with a WebSocketError if the server's response is invalid.

Overloads:

Socket.handshake(req: HTTPClientRequest, cb: (error: WebSocketError | null) => void): void
Socket.handshake(req: HTTPClientRequest, opts: WebSocketHandshakeOptions, cb: (error: WebSocketError | null) => void): void

Parameters

Parameter	Type	Default	Description
`req`	`HTTPClientRequest`	—	The outgoing HTTP request to upgrade; the WebSocket handshake headers are added to it.
`cb`	`(error: WebSocketError \| null) => void`	—	Called once the server's response is validated, with a `WebSocketError` on failure, otherwise `null`.

`Socket.WebSocketEvents`

interface WebSocketEvents {
  message: [payload: Buffer, binary: boolean]
  ping: [payload: Buffer]
  pong: [payload: Buffer]
  data: [data: unknown]
  end: []
  readable: []
  piping: [dest: Writable]
  close: []
  error: [err: Error]
  drain: []
  finish: []
  pipe: [src: Readable]
}

`Socket.WebSocketHandshakeOptions`

interface WebSocketHandshakeOptions {
  timeout?: number
}

`Socket.WebSocketOptions`

interface WebSocketOptions {
  headers?: Record<string, HTTPHeaderValue>
  host?: string
  hostname?: string
  path?: string
  port?: string | number
  secure?: boolean
  socket?: TCPSocket
  isServer?: boolean
  maxPayload?: number
  maxFragments?: number
  handshakeTimeout?: number
  idleTimeout?: number
  closeTimeout?: number
}

host/hostname (an alias for host, for Node.js compatibility), port, and path address the connection. secure uses TLS (wss:) for the underlying connection when true. socket is an already-connected TCP socket to use instead of opening a new connection.

`uncork(): void`

`unshift(data: unknown | null, encoding?: BufferEncoding): boolean`

Parameters

Parameter	Type	Default	Description
`data`	`unknown` \| `null`	—	—
`encoding?`	`BufferEncoding`	—	—

`writable: boolean`

`write(data: unknown, encoding?: BufferEncoding, cb?: StreamCallback): boolean`

Overloads:

write(data: unknown, encoding?: BufferEncoding, cb?: StreamCallback): boolean
write(data: unknown, cb?: StreamCallback): boolean

Parameters

Parameter	Type	Default	Description
`data`	`unknown`	—	—
`encoding?`	`BufferEncoding`	—	—
`cb?`	`StreamCallback`	—	—

Server

`new Server(onconnection: (socket: WebSocket, req: HTTPIncomingMessage) => void)`

Create a server, optionally backed by opts.server, and emit connection for each successful WebSocket upgrade.

Overloads:

new Server(onconnection: (socket: WebSocket, req: HTTPIncomingMessage) => void)
new Server(opts?: WebSocketServerOptions, onconnection?: (socket: WebSocket, req: HTTPIncomingMessage) => void)

Parameters

Parameter	Type	Default	Description
`onconnection`	`(socket: WebSocket, req: HTTPIncomingMessage) => void`	—	Called on each `'connection'` event.

`addListener<E extends keyof M>(name: E, fn: EventHandler<M[E]>): this`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—
`fn`	`EventHandler<M[E]>`	—	—

`addOnceListener<E extends keyof M>(name: E, fn: EventHandler<M[E]>): this`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—
`fn`	`EventHandler<M[E]>`	—	—

`address(): TCPSocketAddress`

Return the bound address of the underlying TCP server.

`close(cb?: (err?: Error | null) => void): this`

Stop the server from accepting new connections and close the ones it has open, calling cb once it has closed. Each connection is sent a close frame and dropped if it has not closed within five seconds, since otherwise a peer that stops taking part would keep the server from ever closing.

Parameters

Parameter	Type	Default	Description
`cb?`	`(err?: Error \| null) => void`	—	Called once the underlying server has closed.

`connections: Set<WebSocket>`

The connections the server has open. A socket handed over by an upgrade is no longer the underlying HTTP server's to close, so these are tracked here and closed by close.

`emit<E extends keyof M>(name: E, ...args: M[E]): boolean`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—
`args`	`M[E]`	—	—

`eventNames(): (keyof M)[]`

`getMaxListeners(): number`

`listenerCount<E extends keyof M>(name: E): number`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—

`listeners<E extends keyof M>(name: E): EventHandler<M[E]>[]`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—

`listening: boolean`

true once the underlying server is bound and accepting connections.

`off<E extends keyof M>(name: E, fn: EventHandler<M[E]>): this`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—
`fn`	`EventHandler<M[E]>`	—	—

`on<E extends keyof M>(name: E, fn: EventHandler<M[E]>): this`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—
`fn`	`EventHandler<M[E]>`	—	—

`once<E extends keyof M>(name: E, fn: EventHandler<M[E]>): this`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—
`fn`	`EventHandler<M[E]>`	—	—

`prependListener<E extends keyof M>(name: E, fn: EventHandler<M[E]>): this`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—
`fn`	`EventHandler<M[E]>`	—	—

`prependOnceListener<E extends keyof M>(name: E, fn: EventHandler<M[E]>): this`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—
`fn`	`EventHandler<M[E]>`	—	—

`rawListeners<E extends keyof M>(name: E): EventHandler<M[E]>[]`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—

`ref(): this`

Ref the underlying server so it keeps the event loop alive.

`removeAllListeners<E extends keyof M>(name?: E): this`

Parameters

Parameter	Type	Default	Description
`name?`	`E`	—	—

`removeListener<E extends keyof M>(name: E, fn: EventHandler<M[E]>): this`

Parameters

Parameter	Type	Default	Description
`name`	`E`	—	—
`fn`	`EventHandler<M[E]>`	—	—

`Server.handshake(req: HTTPIncomingMessage, cb: (err: WebSocketError | null) => void): void`

Perform the server side of the WebSocket opening handshake for req, writing the 101 upgrade response on socket and calling cb with a WebSocketError on failure.

Overloads:

Server.handshake(req: HTTPIncomingMessage, cb: (err: WebSocketError | null) => void): void
Server.handshake(req: HTTPIncomingMessage, socket: TCPSocket, cb: (err: WebSocketError | null) => void): void
Server.handshake(req: HTTPIncomingMessage, socket: TCPSocket, head: Buffer, cb: (err: WebSocketError | null) => void): void

Parameters

Parameter	Type	Default	Description
`req`	`HTTPIncomingMessage`	—	The incoming upgrade request.
`cb`	`(err: WebSocketError \| null) => void`	—	Called with a `WebSocketError` if the request is not a valid WebSocket upgrade, otherwise `null`.

`Server.WebSocketServerEvents`

interface WebSocketServerEvents {
  connection: [socket: WebSocket, req: HTTPIncomingMessage]
  listening: []
  close: []
  error: [err: Error]
  handshakeError: [err: WebSocketError, socket: TCPSocket]
}

`Server.WebSocketServerOptions`

interface WebSocketServerOptions {
  secure?: boolean
  handshakeTimeout?: number
  closeTimeout?: number
  verifyClient?: (req: HTTPIncomingMessage) => boolean | Promise<boolean>
  IncomingMessage?: typeof HTTPIncomingMessage
  ServerResponse?: typeof HTTPServerResponse
  maxPayload?: number
  maxFragments?: number
  idleTimeout?: number
}

secure creates an HTTPS-backed server, accepting wss: connections, when true.

`setMaxListeners(n: number): this`

Parameters

Parameter	Type	Default	Description
`n`	`number`	—	—

`unref(): this`

Unref the underlying server so it does not keep the event loop alive on its own.

`bare-ws/global`

Types

`WebSocketConstructor`

type WebSocketConstructor = typeof ws.Socket

The type of the Socket class, used to type the global WebSocket constructor.

`bare-ws/constants`

Functions

`isValidStatus(code: number): boolean`

Whether a close status may be sent in a close frame.

Parameters

Parameter	Type	Default	Description
`code`	`number`	—	The close status to check.

Returns boolean — false outside the registered ranges, for the reserved 1004, and for the three codes only a local endpoint may report.

Constants and variables

`EOL: string`

The line ending (\r\n) used when writing the handshake response.

`EOF: string`

The blank-line terminator (\r\n\r\n) that ends the handshake response headers.

`GUID: Buffer`

The WebSocket protocol's fixed GUID, concatenated with the Sec-WebSocket-Key to compute the Sec-WebSocket-Accept digest.

`opcode`

opcode: {
  CONTINUATION: number
  TEXT: number
  BINARY: number
  CLOSE: number
  PING: number
  PONG: number
}

The WebSocket frame opcodes (CONTINUATION, TEXT, BINARY, CLOSE, PING, PONG) as defined by RFC 6455.

`status`

status: {
  NORMAL_CLOSURE: number
  GOING_AWAY: number
  PROTOCOL_ERROR: number
  UNSUPPORTED_DATA: number
  NO_STATUS_RECEIVED: number
  ABNORMAL_CLOSURE: number
  INVALID_PAYLOAD: number
  POLICY_VIOLATION: number
  MESSAGE_TOO_LARGE: number
  MISSING_EXTENSION: number
  INTERNAL_ERROR: number
  SERVICE_RESTART: number
  TRY_AGAIN_LATER: number
  BAD_GATEWAY: number
  TLS_HANDSHAKE_FAILURE: number
}

The WebSocket close status codes defined by RFC 6455 and the IANA registry.

`MAX_CONTROL_PAYLOAD_LENGTH: number`

The largest payload a control frame may carry (125), as defined by RFC 6455.

`MAX_PAYLOAD_LENGTH: number`

The default maxPayload, in bytes.

`MAX_FRAGMENTS: number`

The default maxFragments.

`MIN_PAYLOAD_CAPACITY: number`

The smallest buffer a payload is read into before it doubles as it fills, in bytes.

`HANDSHAKE_TIMEOUT: number`

The default handshakeTimeout, in milliseconds.

`IDLE_TIMEOUT: number`

The default idleTimeout, in milliseconds.

`CLOSE_TIMEOUT: number`

How long a connection has to close of its own accord once it has been asked to, in milliseconds, before it is dropped.

`bare-ws/errors`

WebSocketError

`WebSocketError`

new WebSocketError(msg: string, code: string, status: number, fn?: WebSocketError, cause?: unknown)

An error thrown for WebSocket protocol violations, carrying a code and a close status.

Parameters

Parameter	Type	Default	Description
`msg`	`string`	—	The error message.
`code`	`string`	—	The error code.
`status`	`number`	—	The WebSocket close status associated with the error.
`fn?`	`WebSocketError`	—	Optional function to omit from the top of the generated stack trace, passed to `Error.captureStackTrace`.
`cause?`	`unknown`	—	The underlying cause of the error, if any.

`code: string`

The error code, such as 'INVALID_OPCODE'.

`status: number`

The close status reported to the peer before the connection is failed, or 0 for a condition that never reaches the wire.

`WebSocketError.CONNECTION_TIMEOUT(msg?: string): WebSocketError`

No byte arrived from the peer within idleTimeout, and it did not answer the ping that followed.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'CONNECTION_TIMEOUT', for the caller to throw.

`WebSocketError.EXPECTED_CONTINUATION(msg?: string): WebSocketError`

A fragmented message's next frame was not a continuation frame.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'EXPECTED_CONTINUATION', for the caller to throw.

`WebSocketError.EXPECTED_MASK(msg?: string): WebSocketError`

A frame from a client was missing its required mask.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'EXPECTED_MASK', for the caller to throw.

`WebSocketError.INVALID_ACCEPT_HEADER(msg?: string): WebSocketError`

The Sec-WebSocket-Accept header in the server's handshake response did not match the expected digest.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_ACCEPT_HEADER', for the caller to throw.

`WebSocketError.INVALID_CLOSE_PAYLOAD(msg?: string): WebSocketError`

A close frame carried a single byte, which is too short to hold a status.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_CLOSE_PAYLOAD', for the caller to throw.

`WebSocketError.INVALID_CLOSE_STATUS(msg?: string): WebSocketError`

A close frame carried a status that no peer may send.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_CLOSE_STATUS', for the caller to throw.

`WebSocketError.INVALID_CONTROL_PAYLOAD_LENGTH(msg?: string): WebSocketError`

A control frame carried more than the 125 bytes RFC 6455 allows, whether received or passed to ping() or pong().

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_CONTROL_PAYLOAD_LENGTH', for the caller to throw.

`WebSocketError.INVALID_ENCODING(msg?: string): WebSocketError`

Data was written with an encoding other than buffer or utf8, or was not backed by bytes.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_ENCODING', for the caller to throw.

`WebSocketError.INVALID_KEY_HEADER(msg?: string): WebSocketError`

The Sec-WebSocket-Key header was missing or malformed.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_KEY_HEADER', for the caller to throw.

`WebSocketError.INVALID_METHOD(msg?: string): WebSocketError`

The handshake request used a method other than GET.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_METHOD', for the caller to throw.

`WebSocketError.INVALID_OPCODE(msg?: string): WebSocketError`

A frame was received with an opcode that is not TEXT or BINARY.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_OPCODE', for the caller to throw.

`WebSocketError.INVALID_PAYLOAD_LENGTH(msg?: string): WebSocketError`

A frame declared a payload length beyond the safe integer range.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_PAYLOAD_LENGTH', for the caller to throw.

`WebSocketError.INVALID_PROTOCOL(msg?: string): WebSocketError`

A URL was given with a scheme other than ws:, wss:, http: or https:.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_PROTOCOL', for the caller to throw.

`WebSocketError.INVALID_UPGRADE_HEADER(msg?: string): WebSocketError`

The Upgrade header was missing or not websocket.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_UPGRADE_HEADER', for the caller to throw.

`WebSocketError.INVALID_UPGRADE_STATUS(msg?: string): WebSocketError`

The server's handshake response carried a status other than 101.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_UPGRADE_STATUS', for the caller to throw.

`WebSocketError.INVALID_UTF8(msg?: string): WebSocketError`

A text frame or close reason was not well-formed UTF-8.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_UTF8', for the caller to throw.

`WebSocketError.INVALID_VERSION_HEADER(msg?: string): WebSocketError`

The Sec-WebSocket-Version header was neither 8 nor 13.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'INVALID_VERSION_HEADER', for the caller to throw.

`WebSocketError.MESSAGE_TOO_LARGE(msg?: string): WebSocketError`

A frame or reassembled message exceeded maxPayload.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'MESSAGE_TOO_LARGE', for the caller to throw.

`WebSocketError.NETWORK_ERROR(msg: string, cause?: unknown): WebSocketError`

The underlying HTTP request errored before the handshake completed.

Parameters

Parameter	Type	Default	Description
`msg`	`string`	—	The error message.
`cause?`	`unknown`	—	The underlying error.

Returns WebSocketError — A WebSocketError with code set to 'NETWORK_ERROR', for the caller to throw.

`WebSocketError.NOT_CONNECTED(msg?: string): WebSocketError`

An operation, such as ping() or pong(), was attempted before the socket finished connecting, or after it closed.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'NOT_CONNECTED', for the caller to throw.

`WebSocketError.TOO_MANY_FRAGMENTS(msg?: string): WebSocketError`

A message was assembled from more fragments than maxFragments allows.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'TOO_MANY_FRAGMENTS', for the caller to throw.

`WebSocketError.UNEXPECTED_CLOSE(msg?: string): WebSocketError`

The connection went away before a close frame had been exchanged, so part of a message may have been lost.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'UNEXPECTED_CLOSE', for the caller to throw.

`WebSocketError.UNEXPECTED_CONTINUATION(msg?: string): WebSocketError`

A continuation frame was received without a preceding fragmented frame.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'UNEXPECTED_CONTINUATION', for the caller to throw.

`WebSocketError.UNEXPECTED_CONTROL(msg?: string): WebSocketError`

A control frame was fragmented, which RFC 6455 does not allow.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'UNEXPECTED_CONTROL', for the caller to throw.

`WebSocketError.UNEXPECTED_EXTENSION(msg?: string): WebSocketError`

The server's handshake response negotiated an extension, none of which this side ever offers.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'UNEXPECTED_EXTENSION', for the caller to throw.

`WebSocketError.UNEXPECTED_MASK(msg?: string): WebSocketError`

A frame from a server carried a mask, which only a client may set.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'UNEXPECTED_MASK', for the caller to throw.

`WebSocketError.UNEXPECTED_PROTOCOL(msg?: string): WebSocketError`

The server's handshake response named a subprotocol the client did not offer.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'UNEXPECTED_PROTOCOL', for the caller to throw.

`WebSocketError.UNEXPECTED_RSV1(msg?: string): WebSocketError`

A frame was received with the reserved RSV1 bit set.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'UNEXPECTED_RSV1', for the caller to throw.

`WebSocketError.UNEXPECTED_RSV2(msg?: string): WebSocketError`

A frame was received with the reserved RSV2 bit set.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'UNEXPECTED_RSV2', for the caller to throw.

`WebSocketError.UNEXPECTED_RSV3(msg?: string): WebSocketError`

A frame was received with the reserved RSV3 bit set.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'UNEXPECTED_RSV3', for the caller to throw.

`WebSocketError.UPGRADE_REJECTED(msg?: string): WebSocketError`

A server's verifyClient refused the handshake.

Parameters

Parameter	Type	Default	Description
`msg?`	`string`	—	The error message.

Returns WebSocketError — A WebSocketError with code set to 'UPGRADE_REJECTED', for the caller to throw.

bare-ws

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