deno/op_crates/websocket/01_websocket.js
2021-01-06 16:57:28 +01:00

376 lines
9.8 KiB
JavaScript

// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
((window) => {
const core = window.Deno.core;
// provided by "deno_web"
const { URL } = window.__bootstrap.url;
const CONNECTING = 0;
const OPEN = 1;
const CLOSING = 2;
const CLOSED = 3;
function requiredArguments(
name,
length,
required,
) {
if (length < required) {
const errMsg = `${name} requires at least ${required} argument${
required === 1 ? "" : "s"
}, but only ${length} present`;
throw new TypeError(errMsg);
}
}
const handlerSymbol = Symbol("eventHandlers");
function makeWrappedHandler(handler) {
function wrappedHandler(...args) {
if (typeof wrappedHandler.handler !== "function") {
return;
}
return wrappedHandler.handler.call(this, ...args);
}
wrappedHandler.handler = handler;
return wrappedHandler;
}
// TODO(lucacasonato) reuse when we can reuse code between web crates
function defineEventHandler(emitter, name) {
// HTML specification section 8.1.5.1
Object.defineProperty(emitter, `on${name}`, {
get() {
return this[handlerSymbol]?.get(name)?.handler;
},
set(value) {
if (!this[handlerSymbol]) {
this[handlerSymbol] = new Map();
}
let handlerWrapper = this[handlerSymbol]?.get(name);
if (handlerWrapper) {
handlerWrapper.handler = value;
} else {
handlerWrapper = makeWrappedHandler(value);
this.addEventListener(name, handlerWrapper);
}
this[handlerSymbol].set(name, handlerWrapper);
},
configurable: true,
enumerable: true,
});
}
class WebSocket extends EventTarget {
#readyState = CONNECTING;
constructor(url, protocols = []) {
super();
requiredArguments("WebSocket", arguments.length, 1);
const wsURL = new URL(url);
if (wsURL.protocol !== "ws:" && wsURL.protocol !== "wss:") {
throw new DOMException(
"Only ws & wss schemes are allowed in a WebSocket URL.",
"SyntaxError",
);
}
if (wsURL.hash !== "" || wsURL.href.endsWith("#")) {
throw new DOMException(
"Fragments are not allowed in a WebSocket URL.",
"SyntaxError",
);
}
this.#url = wsURL.href;
core.jsonOpSync("op_ws_check_permission", {
url: this.#url,
});
if (protocols && typeof protocols === "string") {
protocols = [protocols];
}
if (
protocols.some((x) => protocols.indexOf(x) !== protocols.lastIndexOf(x))
) {
throw new DOMException(
"Can't supply multiple times the same protocol.",
"SyntaxError",
);
}
core.jsonOpAsync("op_ws_create", {
url: wsURL.href,
protocols: protocols.join(", "),
}).then((create) => {
if (create.success) {
this.#rid = create.rid;
this.#extensions = create.extensions;
this.#protocol = create.protocol;
if (this.#readyState === CLOSING) {
core.jsonOpAsync("op_ws_close", {
rid: this.#rid,
}).then(() => {
this.#readyState = CLOSED;
const errEvent = new ErrorEvent("error");
errEvent.target = this;
this.dispatchEvent(errEvent);
const event = new CloseEvent("close");
event.target = this;
this.dispatchEvent(event);
core.close(this.#rid);
});
} else {
this.#readyState = OPEN;
const event = new Event("open");
event.target = this;
this.dispatchEvent(event);
this.#eventLoop();
}
} else {
this.#readyState = CLOSED;
const errEvent = new ErrorEvent("error");
errEvent.target = this;
this.dispatchEvent(errEvent);
const closeEvent = new CloseEvent("close");
closeEvent.target = this;
this.dispatchEvent(closeEvent);
}
}).catch((err) => {
this.#readyState = CLOSED;
const errorEv = new ErrorEvent(
"error",
{ error: err, message: err.toString() },
);
errorEv.target = this;
this.dispatchEvent(errorEv);
const closeEv = new CloseEvent("close");
closeEv.target = this;
this.dispatchEvent(closeEv);
});
}
get CONNECTING() {
return CONNECTING;
}
get OPEN() {
return OPEN;
}
get CLOSING() {
return CLOSING;
}
get CLOSED() {
return CLOSED;
}
get readyState() {
return this.#readyState;
}
#extensions = "";
#protocol = "";
#url = "";
#rid;
get extensions() {
return this.#extensions;
}
get protocol() {
return this.#protocol;
}
#binaryType = "blob";
get binaryType() {
return this.#binaryType;
}
set binaryType(value) {
if (value === "blob" || value === "arraybuffer") {
this.#binaryType = value;
}
}
#bufferedAmount = 0;
get bufferedAmount() {
return this.#bufferedAmount;
}
get url() {
return this.#url;
}
send(data) {
requiredArguments("WebSocket.send", arguments.length, 1);
if (this.#readyState != OPEN) {
throw Error("readyState not OPEN");
}
const sendTypedArray = (ta) => {
this.#bufferedAmount += ta.size;
core.jsonOpAsync("op_ws_send", {
rid: this.#rid,
kind: "binary",
}, ta).then(() => {
this.#bufferedAmount -= ta.size;
});
};
if (data instanceof Blob) {
data.slice().arrayBuffer().then((ab) =>
sendTypedArray(new DataView(ab))
);
} else if (
data instanceof Int8Array || data instanceof Int16Array ||
data instanceof Int32Array || data instanceof Uint8Array ||
data instanceof Uint16Array || data instanceof Uint32Array ||
data instanceof Uint8ClampedArray || data instanceof Float32Array ||
data instanceof Float64Array || data instanceof DataView
) {
sendTypedArray(data);
} else if (data instanceof ArrayBuffer) {
sendTypedArray(new DataView(data));
} else {
const string = String(data);
const encoder = new TextEncoder();
const d = encoder.encode(string);
this.#bufferedAmount += d.size;
core.jsonOpAsync("op_ws_send", {
rid: this.#rid,
kind: "text",
text: string,
}).then(() => {
this.#bufferedAmount -= d.size;
});
}
}
close(code, reason) {
if (code && (code !== 1000 && !(3000 <= code > 5000))) {
throw new DOMException(
"The close code must be either 1000 or in the range of 3000 to 4999.",
"NotSupportedError",
);
}
const encoder = new TextEncoder();
if (reason && encoder.encode(reason).byteLength > 123) {
throw new DOMException(
"The close reason may not be longer than 123 bytes.",
"SyntaxError",
);
}
if (this.#readyState === CONNECTING) {
this.#readyState = CLOSING;
} else if (this.#readyState === OPEN) {
this.#readyState = CLOSING;
core.jsonOpAsync("op_ws_close", {
rid: this.#rid,
code,
reason,
}).then(() => {
this.#readyState = CLOSED;
const event = new CloseEvent("close", {
wasClean: true,
code,
reason,
});
event.target = this;
this.dispatchEvent(event);
core.close(this.#rid);
});
}
}
async #eventLoop() {
if (this.#readyState === OPEN) {
const message = await core.jsonOpAsync(
"op_ws_next_event",
{ rid: this.#rid },
);
if (message.type === "string" || message.type === "binary") {
let data;
if (message.type === "string") {
data = message.data;
} else {
if (this.binaryType === "blob") {
data = new Blob([new Uint8Array(message.data)]);
} else {
data = new Uint8Array(message.data).buffer;
}
}
const event = new MessageEvent("message", {
data,
origin: this.#url,
});
event.target = this;
this.dispatchEvent(event);
this.#eventLoop();
} else if (message.type === "ping") {
core.jsonOpAsync("op_ws_send", {
rid: this.#rid,
kind: "pong",
});
this.#eventLoop();
} else if (message.type === "close") {
this.#readyState = CLOSED;
const event = new CloseEvent("close", {
wasClean: true,
code: message.code,
reason: message.reason,
});
event.target = this;
this.dispatchEvent(event);
} else if (message.type === "error") {
this.#readyState = CLOSED;
const errorEv = new ErrorEvent("error");
errorEv.target = this;
this.dispatchEvent(errorEv);
this.#readyState = CLOSED;
const closeEv = new CloseEvent("close");
closeEv.target = this;
this.dispatchEvent(closeEv);
}
}
}
}
Object.defineProperties(WebSocket, {
CONNECTING: {
value: 0,
},
OPEN: {
value: 1,
},
CLOSING: {
value: 2,
},
CLOSED: {
value: 3,
},
});
defineEventHandler(WebSocket.prototype, "message");
defineEventHandler(WebSocket.prototype, "error");
defineEventHandler(WebSocket.prototype, "close");
defineEventHandler(WebSocket.prototype, "open");
window.__bootstrap.webSocket = { WebSocket };
})(this);