include/websock.js: client library for websockify.

The Websock object from websock.js is similar to the standard
WebSocket object but Websock enables communication with raw TCP
sockets (i.e. the binary stream) via websockify. This is accomplished
by base64 encoding the data stream between Websock and websockify.

Websock has built-in receive queue buffering; the message event
does not contain actual data but is simply a notification that
there is new data available. Several rQ* methods are available to
read binary data off of the receive queue.
This commit is contained in:
Joel Martin 2011-01-13 00:17:01 -06:00
parent 6d1e216115
commit 124f28c63a
2 changed files with 329 additions and 2 deletions

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@ -1,6 +1,6 @@
## websockify: WebSockets support for any application/server
websockify was formerly named `wsproxy` and was part of the
websockify was formerly named wsproxy and was part of the
[noVNC](https://github.com/kanaka/noVNC) project.
At the most basic level, websockify just translates WebSockets traffic
@ -15,6 +15,20 @@ case the data from the client is not a full WebSockets frame (i.e.
does not end in 255).
### Websock Javascript library
The `include/websock.js` Javascript library library provides a Websock
object that is similar to the standard WebSocket object but Websock
enables communication with raw TCP sockets (i.e. the binary stream)
via websockify. This is accomplished by base64 encoding the data
stream between Websock and websockify.
Websock has built-in receive queue buffering; the message event
does not contain actual data but is simply a notification that
there is new data available. Several rQ* methods are available to
read binary data off of the receive queue.
### Additional websockify features
These are not necessary for the basic operation.
@ -49,7 +63,7 @@ These are not necessary for the basic operation.
The primary implementation of websockify is in python. There are two
other implementations of websockify in C, and Node (node.js) in the
`other` directory.
`other/` subdirectory.
Here is the feature support matrix for the the websockify
implementations:

313
include/websock.js Normal file
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/*
* Websock: high-performance binary WebSockets
* Copyright (C) 2011 Joel Martin
* Licensed under LGPL-3 (see LICENSE.txt)
*
* Websock is similar to the standard WebSocket object but Websock
* enables communication with raw TCP sockets (i.e. the binary stream)
* via websockify. This is accomplished by base64 encoding the data
* stream between Websock and websockify.
*
* Websock has built-in receive queue buffering; the message event
* does not contain actual data but is simply a notification that
* there is new data available. Several rQ* methods are available to
* read binary data off of the receive queue.
*/
// Load Flash WebSocket emulator if needed
if (window.WebSocket) {
Websock_native = true;
} else {
/* no builtin WebSocket so load web_socket.js */
Websock_native = false;
(function () {
function get_INCLUDE_URI() {
return (typeof INCLUDE_URI !== "undefined") ?
INCLUDE_URI : "include/";
}
var start = "<script src='" + get_INCLUDE_URI(),
end = "'><\/script>", extra = "";
WEB_SOCKET_SWF_LOCATION = get_INCLUDE_URI() +
"web-socket-js/WebSocketMain.swf";
extra += start + "web-socket-js/swfobject.js" + end;
extra += start + "web-socket-js/FABridge.js" + end;
extra += start + "web-socket-js/web_socket.js" + end;
document.write(extra);
}());
}
function Websock() {
var api = {}, // Public API
websocket = null, // WebSocket object
rQ = [], // Receive queue
rQi = 0, // Receive queue index
rQmax = 10000, // Max receive queue size before compacting
sQ = [], // Send queue
eventHandlers = {
'message' : function() {},
'open' : function() {},
'close' : function() {},
'error' : function() {}
};
//
// Queue public functions
//
function get_sQ() {
return sQ;
}
function get_rQ() {
return rQ;
}
function get_rQi() {
return rQi;
}
set_rQi = function(val) {
rQi = val;
}
function rQlen() {
return rQ.length - rQi;
}
function rQpeek8() {
return (rQ[rQi] );
}
function rQshift8() {
return (rQ[rQi++] );
}
function rQunshift8(num) {
if (rQi === 0) {
rQ.unshift(num);
} else {
rQi -= 1;
rQ[rQi] = num;
}
}
function rQshift16() {
return (rQ[rQi++] << 8) +
(rQ[rQi++] );
}
function rQshift32() {
return (rQ[rQi++] << 24) +
(rQ[rQi++] << 16) +
(rQ[rQi++] << 8) +
(rQ[rQi++] );
}
function rQshiftStr(len) {
var arr = rQ.slice(rQi, rQi + len);
rQi += len;
return arr.map(function (num) {
return String.fromCharCode(num); } ).join('');
}
function rQshiftBytes(len) {
rQi += len;
return rQ.slice(rQi-len, rQi);
}
function rQslice(start, end) {
if (end) {
return rQ.slice(rQi + start, rQi + end);
} else {
return rQ.slice(rQi + start);
}
}
// Check to see if we must wait for 'num' bytes (default to FBU.bytes)
// to be available in the receive queue. Return true if we need to
// wait (and possibly print a debug message), otherwise false.
function rQwait(msg, num, goback) {
var rQlen = rQ.length - rQi; // Skip rQlen() function call
if (rQlen < num) {
if (goback) {
if (rQi < goback) {
throw("rQwait cannot backup " + goback + " bytes");
}
rQi -= goback;
}
//Util.Debug(" waiting for " + (num-rQlen) +
// " " + msg + " byte(s)");
return true; // true means need more data
}
return false;
}
//
// Private utility routines
//
function encode_message() {
/* base64 encode */
return Base64.encode(sQ);
}
function decode_message(data) {
//Util.Debug(">> decode_message: " + data);
/* base64 decode */
rQ = rQ.concat(Base64.decode(data, 0));
//Util.Debug(">> decode_message, rQ: " + rQ);
}
//
// Public Send functions
//
function flush() {
if (websocket.bufferedAmount === 0) {
//Util.Debug("arr: " + arr);
//Util.Debug("sQ: " + sQ);
if (sQ) {
websocket.send(encode_message(sQ));
sQ = [];
}
return true;
} else {
Util.Debug("Delaying send");
return false;
}
}
// overridable for testing
function send(arr) {
//Util.Debug(">> send_array: " + arr);
sQ = sQ.concat(arr);
flush();
};
function send_string(str) {
//Util.Debug(">> send_string: " + str);
api.send_array(str.split('').map(
function (chr) { return chr.charCodeAt(0); } ) );
}
//
// Other public functions
function recv_message(e) {
//Util.Debug(">> recv_message: " + e.data.length);
try {
decode_message(e.data);
if (rQlen() > 0) {
eventHandlers['message']();
// Compact the receive queue
if (rQ.length > rQmax) {
//Util.Debug("Compacting receive queue");
rQ = rQ.slice(rQi);
rQi = 0;
}
} else {
Util.Debug("Ignoring empty message");
}
} catch (exc) {
if (typeof exc.stack !== 'undefined') {
Util.Warn("recv_message, caught exception: " + exc.stack);
} else if (typeof exc.description !== 'undefined') {
Util.Warn("recv_message, caught exception: " + exc.description);
} else {
Util.Warn("recv_message, caught exception:" + exc);
}
if (typeof exc.name !== 'undefined') {
eventHandlers['error'](exc.name + ": " + exc.message);
} else {
eventHandlers['error'](exc);
}
}
//Util.Debug("<< recv_message");
};
// Set event handlers
function on(evt, handler) {
eventHandlers[evt] = handler;
}
function init() {
rQ = [];
rQi = 0;
sQ = [];
websocket = null;
}
function open(uri) {
init();
websocket = new WebSocket(uri);
websocket.onmessage = recv_message;
websocket.onopen = function(e) {
Util.Debug(">> WebSock.onopen");
eventHandlers['open']();
Util.Debug("<< WebSock.onopen");
}
websocket.onclose = function(e) {
Util.Debug(">> WebSock.onclose");
eventHandlers['close']();
Util.Debug("<< WebSock.onclose");
}
websocket.onerror = function(e) {
Util.Debug("<< WebSock.onerror: " + e);
eventHandlers['error'](e);
Util.Debug("<< WebSock.onerror: ");
}
}
function close() {
if (websocket) {
if ((websocket.readyState === WebSocket.OPEN) ||
(websocket.readyState === WebSocket.CONNECTING)) {
Util.Info("Closing WebSocket connection");
websocket.close();
}
websocket.onmessage = function (e) { return; };
}
}
function constructor() {
// Direct access to send and receive queues
api.get_sQ = get_sQ;
api.get_rQ = get_rQ;
api.get_rQi = get_rQi;
api.set_rQi = set_rQi;
// Routines to read from the receive queue
api.rQlen = rQlen;
api.rQpeek8 = rQpeek8;
api.rQshift8 = rQshift8;
api.rQunshift8 = rQunshift8;
api.rQshift16 = rQshift16;
api.rQshift32 = rQshift32;
api.rQshiftStr = rQshiftStr;
api.rQshiftBytes = rQshiftBytes;
api.rQslice = rQslice;
api.rQwait = rQwait;
api.flush = flush;
api.send_array = send_array;
api.send_string = send_string;
api.recv_message = recv_message;
api.on = on;
api.init = init;
api.open = open;
api.close = close;
return api;
}
return constructor();
}