'use strict'
const { webidl } = require('../fetch/webidl')
const { DOMException } = require('../fetch/constants')
const { URLSerializer } = require('../fetch/dataURL')
const { getGlobalOrigin } = require('../fetch/global')
const { staticPropertyDescriptors, states, opcodes, emptyBuffer } = require('./constants')
const {
kWebSocketURL,
kReadyState,
kController,
kBinaryType,
kResponse,
kSentClose,
kByteParser
} = require('./symbols')
const { isEstablished, isClosing, isValidSubprotocol, failWebsocketConnection, fireEvent } = require('./util')
const { establishWebSocketConnection } = require('./connection')
const { WebsocketFrameSend } = require('./frame')
const { ByteParser } = require('./receiver')
const { kEnumerableProperty, isBlobLike } = require('../core/util')
const { getGlobalDispatcher } = require('../global')
const { types } = require('util')
let experimentalWarned = false
// https://websockets.spec.whatwg.org/#interface-definition
class WebSocket extends EventTarget {
#events = {
open: null,
error: null,
close: null,
message: null
}
#bufferedAmount = 0
#protocol = ''
#extensions = ''
/**
* @param {string} url
* @param {string|string[]} protocols
*/
constructor (url, protocols = []) {
super()
webidl.argumentLengthCheck(arguments, 1, { header: 'WebSocket constructor' })
if (!experimentalWarned) {
experimentalWarned = true
process.emitWarning('WebSockets are experimental, expect them to change at any time.', {
code: 'UNDICI-WS'
})
}
const options = webidl.converters['DOMString or sequence<DOMString> or WebSocketInit'](protocols)
url = webidl.converters.USVString(url)
protocols = options.protocols
// 1. Let baseURL be this's relevant settings object's API base URL.
const baseURL = getGlobalOrigin()
// 1. Let urlRecord be the result of applying the URL parser to url with baseURL.
let urlRecord
try {
urlRecord = new URL(url, baseURL)
} catch (e) {
// 3. If urlRecord is failure, then throw a "SyntaxError" DOMException.
throw new DOMException(e, 'SyntaxError')
}
// 4. If urlRecord’s scheme is "http", then set urlRecord’s scheme to "ws".
if (urlRecord.protocol === 'http:') {
urlRecord.protocol = 'ws:'
} else if (urlRecord.protocol === 'https:') {
// 5. Otherwise, if urlRecord’s scheme is "https", set urlRecord’s scheme to "wss".
urlRecord.protocol = 'wss:'
}
// 6. If urlRecord’s scheme is not "ws" or "wss", then throw a "SyntaxError" DOMException.
if (urlRecord.protocol !== 'ws:' && urlRecord.protocol !== 'wss:') {
throw new DOMException(
`Expected a ws: or wss: protocol, got ${urlRecord.protocol}`,
'SyntaxError'
)
}
// 7. If urlRecord’s fragment is non-null, then throw a "SyntaxError"
// DOMException.
if (urlRecord.hash || urlRecord.href.endsWith('#')) {
throw new DOMException('Got fragment', 'SyntaxError')
}
// 8. If protocols is a string, set protocols to a sequence consisting
// of just that string.
if (typeof protocols === 'string') {
protocols = [protocols]
}
// 9. If any of the values in protocols occur more than once or otherwise
// fail to match the requirements for elements that comprise the value
// of `Sec-WebSocket-Protocol` fields as defined by The WebSocket
// protocol, then throw a "SyntaxError" DOMException.
if (protocols.length !== new Set(protocols.map(p => p.toLowerCase())).size) {
throw new DOMException('Invalid Sec-WebSocket-Protocol value', 'SyntaxError')
}
if (protocols.length > 0 && !protocols.every(p => isValidSubprotocol(p))) {
throw new DOMException('Invalid Sec-WebSocket-Protocol value', 'SyntaxError')
}
// 10. Set this's url to urlRecord.
this[kWebSocketURL] = new URL(urlRecord.href)
// 11. Let client be this's relevant settings object.
// 12. Run this step in parallel:
// 1. Establish a WebSocket connection given urlRecord, protocols,
// and client.
this[kController] = establishWebSocketConnection(
urlRecord,
protocols,
this,
(response) => this.#onConnectionEstablished(response),
options
)
// Each WebSocket object has an associated ready state, which is a
// number representing the state of the connection. Initially it must
// be CONNECTING (0).
this[kReadyState] = WebSocket.CONNECTING
// The extensions attribute must initially return the empty string.
// The protocol attribute must initially return the empty string.
// Each WebSocket object has an associated binary type, which is a
// BinaryType. Initially it must be "blob".
this[kBinaryType] = 'blob'
}
/**
* @see https://websockets.spec.whatwg.org/#dom-websocket-close
* @param {number|undefined} code
* @param {string|undefined} reason
*/
close (code = undefined, reason = undefined) {
webidl.brandCheck(this, WebSocket)
if (code !== undefined) {
code = webidl.converters['unsigned short'](code, { clamp: true })
}
if (reason !== undefined) {
reason = webidl.converters.USVString(reason)
}
// 1. If code is present, but is neither an integer equal to 1000 nor an
// integer in the range 3000 to 4999, inclusive, throw an
// "InvalidAccessError" DOMException.
if (code !== undefined) {
if (code !== 1000 && (code < 3000 || code > 4999)) {
throw new DOMException('invalid code', 'InvalidAccessError')
}
}
let reasonByteLength = 0
// 2. If reason is present, then run these substeps:
if (reason !== undefined) {
// 1. Let reasonBytes be the result of encoding reason.
// 2. If reasonBytes is longer than 123 bytes, then throw a
// "SyntaxError" DOMException.
reasonByteLength = Buffer.byteLength(reason)
if (reasonByteLength > 123) {
throw new DOMException(
`Reason must be less than 123 bytes; received ${reasonByteLength}`,
'SyntaxError'
)
}
}
// 3. Run the first matching steps from the following list:
if (this[kReadyState] === WebSocket.CLOSING || this[kReadyState] === WebSocket.CLOSED) {
// If this's ready state is CLOSING (2) or CLOSED (3)
// Do nothing.
} else if (!isEstablished(this)) {
// If the WebSocket connection is not yet established
// Fail the WebSocket connection and set this's ready state
// to CLOSING (2).
failWebsocketConnection(this, 'Connection was closed before it was established.')
this[kReadyState] = WebSocket.CLOSING
} else if (!isClosing(this)) {
// If the WebSocket closing handshake has not yet been started
// Start the WebSocket closing handshake and set this's ready
// state to CLOSING (2).
// - If neither code nor reason is present, the WebSocket Close
// message must not have a body.
// - If code is present, then the status code to use in the
// WebSocket Close message must be the integer given by code.
// - If reason is also present, then reasonBytes must be
// provided in the Close message after the status code.
const frame = new WebsocketFrameSend()
// If neither code nor reason is present, the WebSocket Close
// message must not have a body.
// If code is present, then the status code to use in the
// WebSocket Close message must be the integer given by code.
if (code !== undefined && reason === undefined) {
frame.frameData = Buffer.allocUnsafe(2)
frame.frameData.writeUInt16BE(code, 0)
} else if (code !== undefined && reason !== undefined) {
// If reason is also present, then reasonBytes must be
// provided in the Close message after the status code.
frame.frameData = Buffer.allocUnsafe(2 + reasonByteLength)
frame.frameData.writeUInt16BE(code, 0)
// the body MAY contain UTF-8-encoded data with value /reason/
frame.frameData.write(reason, 2, 'utf-8')
} else {
frame.frameData = emptyBuffer
}
/** @type {import('stream').Duplex} */
const socket = this[kResponse].socket
socket.write(frame.createFrame(opcodes.CLOSE), (err) => {
if (!err) {
this[kSentClose] = true
}
})
// Upon either sending or receiving a Close control frame, it is said
// that _The WebSocket Closing Handshake is Started_ and that the
// WebSocket connection is in the CLOSING state.
this[kReadyState] = states.CLOSING
} else {
// Otherwise
// Set this's ready state to CLOSING (2).
this[kReadyState] = WebSocket.CLOSING
}
}
/**
* @see https://websockets.spec.whatwg.org/#dom-websocket-send
* @param {NodeJS.TypedArray|ArrayBuffer|Blob|string} data
*/
send (data) {
webidl.brandCheck(this, WebSocket)
webidl.argumentLengthCheck(arguments, 1, { header: 'WebSocket.send' })
data = webidl.converters.WebSocketSendData(data)
// 1. If this's ready state is CONNECTING, then throw an
// "InvalidStateError" DOMException.
if (this[kReadyState] === WebSocket.CONNECTING) {
throw new DOMException('Sent before connected.', 'InvalidStateError')
}
// 2. Run the appropriate set of steps from the following list:
// https://datatracker.ietf.org/doc/html/rfc6455#section-6.1
// https://datatracker.ietf.org/doc/html/rfc6455#section-5.2
if (!isEstablished(this) || isClosing(this)) {
return
}
/** @type {import('stream').Duplex} */
const socket = this[kResponse].socket
// If data is a string
if (typeof data === 'string') {
// If the WebSocket connection is established and the WebSocket
// closing handshake has not yet started, then the user agent
// must send a WebSocket Message comprised of the data argument
// using a text frame opcode; if the data cannot be sent, e.g.
// because it would need to be buffered but the buffer is full,
// the user agent must flag the WebSocket as full and then close
// the WebSocket connection. Any invocation of this method with a
// string argument that does not throw an exception must increase
// the bufferedAmount attribute by the number of bytes needed to
// express the argument as UTF-8.
const value = Buffer.from(data)
const frame = new WebsocketFrameSend(value)
const buffer = frame.createFrame(opcodes.TEXT)
this.#bufferedAmount += value.byteLength
socket.write(buffer, () => {
this.#bufferedAmount -= value.byteLength
})
} else if (types.isArrayBuffer(data)) {
// If the WebSocket connection is established, and the WebSocket
// closing handshake has not yet started, then the user agent must
// send a WebSocket Message comprised of data using a binary frame
// opcode; if the data cannot be sent, e.g. because it would need
// to be buffered but the buffer is full, the user agent must flag
// the WebSocket as full and then close the WebSocket connection.
// The data to be sent is the data stored in the buffer described
// by the ArrayBuffer object. Any invocation of this method with an
// ArrayBuffer argument that does not throw an exception must
// increase the bufferedAmount attribute by the length of the
// ArrayBuffer in bytes.
const value = Buffer.from(data)
const frame = new WebsocketFrameSend(value)
const buffer = frame.createFrame(opcodes.BINARY)
this.#bufferedAmount += value.byteLength
socket.write(buffer, () => {
this.#bufferedAmount -= value.byteLength
})
} else if (ArrayBuffer.isView(data)) {
// If the WebSocket connection is established, and the WebSocket
// closing handshake has not yet started, then the user agent must
// send a WebSocket Message comprised of data using a binary frame
// opcode; if the data cannot be sent, e.g. because it would need to
// be buffered but the buffer is full, the user agent must flag the
// WebSocket as full and then close the WebSocket connection. The
// data to be sent is the data stored in the section of the buffer
// described by the ArrayBuffer object that data references. Any
// invocation of this method with this kind of argument that does
// not throw an exception must increase the bufferedAmount attribute
// by the length of data’s buffer in bytes.
const ab = Buffer.from(data, data.byteOffset, data.byteLength)
const frame = new WebsocketFrameSend(ab)
const buffer = frame.createFrame(opcodes.BINARY)
this.#bufferedAmount += ab.byteLength
socket.write(buffer, () => {
this.#bufferedAmount -= ab.byteLength
})
} else if (isBlobLike(data)) {
// If the WebSocket connection is established, and the WebSocket
// closing handshake has not yet started, then the user agent must
// send a WebSocket Message comprised of data using a binary frame
// opcode; if the data cannot be sent, e.g. because it would need to
// be buffered but the buffer is full, the user agent must flag the
// WebSocket as full and then close the WebSocket connection. The data
// to be sent is the raw data represented by the Blob object. Any
// invocation of this method with a Blob argument that does not throw
// an exception must increase the bufferedAmount attribute by the size
// of the Blob object’s raw data, in bytes.
const frame = new WebsocketFrameSend()
data.arrayBuffer().then((ab) => {
const value = Buffer.from(ab)
frame.frameData = value
const buffer = frame.createFrame(opcodes.BINARY)
this.#bufferedAmount += value.byteLength
socket.write(buffer, () => {
this.#bufferedAmount -= value.byteLength
})
})
}
}
get readyState () {
webidl.brandCheck(this, WebSocket)
// The readyState getter steps are to return this's ready state.
return this[kReadyState]
}
get bufferedAmount () {
webidl.brandCheck(this, WebSocket)
return this.#bufferedAmount
}
get url () {
webidl.brandCheck(this, WebSocket)
// The url getter steps are to return this's url, serialized.
return URLSerializer(this[kWebSocketURL])
}
get extensions () {
webidl.brandCheck(this, WebSocket)
return this.#extensions
}
get protocol () {
webidl.brandCheck(this, WebSocket)
return this.#protocol
}
get onopen () {
webidl.brandCheck(this, WebSocket)
return this.#events.open
}
set onopen (fn) {
webidl.brandCheck(this, WebSocket)
if (this.#events.open) {
this.removeEventListener('open', this.#events.open)
}
if (typeof fn === 'function') {
this.#events.open = fn
this.addEventListener('open', fn)
} else {
this.#events.open = null
}
}
get onerror () {
webidl.brandCheck(this, WebSocket)
return this.#events.error
}
set onerror (fn) {
webidl.brandCheck(this, WebSocket)
if (this.#events.error) {
this.removeEventListener('error', this.#events.error)
}
if (typeof fn === 'function') {
this.#events.error = fn
this.addEventListener('error', fn)
} else {
this.#events.error = null
}
}
get onclose () {
webidl.brandCheck(this, WebSocket)
return this.#events.close
}
set onclose (fn) {
webidl.brandCheck(this, WebSocket)
if (this.#events.close) {
this.removeEventListener('close', this.#events.close)
}
if (typeof fn === 'function') {
this.#events.close = fn
this.addEventListener('close', fn)
} else {
this.#events.close = null
}
}
get onmessage () {
webidl.brandCheck(this, WebSocket)
return this.#events.message
}
set onmessage (fn) {
webidl.brandCheck(this, WebSocket)
if (this.#events.message) {
this.removeEventListener('message', this.#events.message)
}
if (typeof fn === 'function') {
this.#events.message = fn
this.addEventListener('message', fn)
} else {
this.#events.message = null
}
}
get binaryType () {
webidl.brandCheck(this, WebSocket)
return this[kBinaryType]
}
set binaryType (type) {
webidl.brandCheck(this, WebSocket)
if (type !== 'blob' && type !== 'arraybuffer') {
this[kBinaryType] = 'blob'
} else {
this[kBinaryType] = type
}
}
/**
* @see https://websockets.spec.whatwg.org/#feedback-from-the-protocol
*/
#onConnectionEstablished (response) {
// processResponse is called when the "response’s header list has been received and initialized."
// once this happens, the connection is open
this[kResponse] = response
const parser = new ByteParser(this)
parser.on('drain', function onParserDrain () {
this.ws[kResponse].socket.resume()
})
response.socket.ws = this
this[kByteParser] = parser
// 1. Change the ready state to OPEN (1).
this[kReadyState] = states.OPEN
// 2. Change the extensions attribute’s value to the extensions in use, if
// it is not the null value.
// https://datatracker.ietf.org/doc/html/rfc6455#section-9.1
const extensions = response.headersList.get('sec-websocket-extensions')
if (extensions !== null) {
this.#extensions = extensions
}
// 3. Change the protocol attribute’s value to the subprotocol in use, if
// it is not the null value.
// https://datatracker.ietf.org/doc/html/rfc6455#section-1.9
const protocol = response.headersList.get('sec-websocket-protocol')
if (protocol !== null) {
this.#protocol = protocol
}
// 4. Fire an event named open at the WebSocket object.
fireEvent('open', this)
}
}
// https://websockets.spec.whatwg.org/#dom-websocket-connecting
WebSocket.CONNECTING = WebSocket.prototype.CONNECTING = states.CONNECTING
// https://websockets.spec.whatwg.org/#dom-websocket-open
WebSocket.OPEN = WebSocket.prototype.OPEN = states.OPEN
// https://websockets.spec.whatwg.org/#dom-websocket-closing
WebSocket.CLOSING = WebSocket.prototype.CLOSING = states.CLOSING
// https://websockets.spec.whatwg.org/#dom-websocket-closed
WebSocket.CLOSED = WebSocket.prototype.CLOSED = states.CLOSED
Object.defineProperties(WebSocket.prototype, {
CONNECTING: staticPropertyDescriptors,
OPEN: staticPropertyDescriptors,
CLOSING: staticPropertyDescriptors,
CLOSED: staticPropertyDescriptors,
url: kEnumerableProperty,
readyState: kEnumerableProperty,
bufferedAmount: kEnumerableProperty,
onopen: kEnumerableProperty,
onerror: kEnumerableProperty,
onclose: kEnumerableProperty,
close: kEnumerableProperty,
onmessage: kEnumerableProperty,
binaryType: kEnumerableProperty,
send: kEnumerableProperty,
extensions: kEnumerableProperty,
protocol: kEnumerableProperty,
[Symbol.toStringTag]: {
value: 'WebSocket',
writable: false,
enumerable: false,
configurable: true
}
})
Object.defineProperties(WebSocket, {
CONNECTING: staticPropertyDescriptors,
OPEN: staticPropertyDescriptors,
CLOSING: staticPropertyDescriptors,
CLOSED: staticPropertyDescriptors
})
webidl.converters['sequence<DOMString>'] = webidl.sequenceConverter(
webidl.converters.DOMString
)
webidl.converters['DOMString or sequence<DOMString>'] = function (V) {
if (webidl.util.Type(V) === 'Object' && Symbol.iterator in V) {
return webidl.converters['sequence<DOMString>'](V)
}
return webidl.converters.DOMString(V)
}
// This implements the propsal made in https://github.com/whatwg/websockets/issues/42
webidl.converters.WebSocketInit = webidl.dictionaryConverter([
{
key: 'protocols',
converter: webidl.converters['DOMString or sequence<DOMString>'],
get defaultValue () {
return []
}
},
{
key: 'dispatcher',
converter: (V) => V,
get defaultValue () {
return getGlobalDispatcher()
}
},
{
key: 'headers',
converter: webidl.nullableConverter(webidl.converters.HeadersInit)
}
])
webidl.converters['DOMString or sequence<DOMString> or WebSocketInit'] = function (V) {
if (webidl.util.Type(V) === 'Object' && !(Symbol.iterator in V)) {
return webidl.converters.WebSocketInit(V)
}
return { protocols: webidl.converters['DOMString or sequence<DOMString>'](V) }
}
webidl.converters.WebSocketSendData = function (V) {
if (webidl.util.Type(V) === 'Object') {
if (isBlobLike(V)) {
return webidl.converters.Blob(V, { strict: false })
}
if (ArrayBuffer.isView(V) || types.isAnyArrayBuffer(V)) {
return webidl.converters.BufferSource(V)
}
}
return webidl.converters.USVString(V)
}
module.exports = {
WebSocket
}
