comparison node_modules/xmlhttprequest/lib/XMLHttpRequest.js @ 77:cd921abc8887

added puredata trigger/OSC router
author Rob Canning <rob@foo.net>
date Tue, 15 Jul 2014 17:48:07 +0100
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76:0ae87af84e2f 77:cd921abc8887
1 /**
2 * Wrapper for built-in http.js to emulate the browser XMLHttpRequest object.
3 *
4 * This can be used with JS designed for browsers to improve reuse of code and
5 * allow the use of existing libraries.
6 *
7 * Usage: include("XMLHttpRequest.js") and use XMLHttpRequest per W3C specs.
8 *
9 * @author Dan DeFelippi <dan@driverdan.com>
10 * @contributor David Ellis <d.f.ellis@ieee.org>
11 * @license MIT
12 */
13
14 var Url = require("url")
15 , spawn = require("child_process").spawn
16 , fs = require('fs');
17
18 exports.XMLHttpRequest = function() {
19 /**
20 * Private variables
21 */
22 var self = this;
23 var http = require('http');
24 var https = require('https');
25
26 // Holds http.js objects
27 var request;
28 var response;
29
30 // Request settings
31 var settings = {};
32
33 // Disable header blacklist.
34 // Not part of XHR specs.
35 var disableHeaderCheck = false;
36
37 // Set some default headers
38 var defaultHeaders = {
39 "User-Agent": "node-XMLHttpRequest",
40 "Accept": "*/*",
41 };
42
43 var headers = defaultHeaders;
44
45 // These headers are not user setable.
46 // The following are allowed but banned in the spec:
47 // * user-agent
48 var forbiddenRequestHeaders = [
49 "accept-charset",
50 "accept-encoding",
51 "access-control-request-headers",
52 "access-control-request-method",
53 "connection",
54 "content-length",
55 "content-transfer-encoding",
56 "cookie",
57 "cookie2",
58 "date",
59 "expect",
60 "host",
61 "keep-alive",
62 "origin",
63 "referer",
64 "te",
65 "trailer",
66 "transfer-encoding",
67 "upgrade",
68 "via"
69 ];
70
71 // These request methods are not allowed
72 var forbiddenRequestMethods = [
73 "TRACE",
74 "TRACK",
75 "CONNECT"
76 ];
77
78 // Send flag
79 var sendFlag = false;
80 // Error flag, used when errors occur or abort is called
81 var errorFlag = false;
82
83 // Event listeners
84 var listeners = {};
85
86 /**
87 * Constants
88 */
89
90 this.UNSENT = 0;
91 this.OPENED = 1;
92 this.HEADERS_RECEIVED = 2;
93 this.LOADING = 3;
94 this.DONE = 4;
95
96 /**
97 * Public vars
98 */
99
100 // Current state
101 this.readyState = this.UNSENT;
102
103 // default ready state change handler in case one is not set or is set late
104 this.onreadystatechange = null;
105
106 // Result & response
107 this.responseText = "";
108 this.responseXML = "";
109 this.status = null;
110 this.statusText = null;
111
112 /**
113 * Private methods
114 */
115
116 /**
117 * Check if the specified header is allowed.
118 *
119 * @param string header Header to validate
120 * @return boolean False if not allowed, otherwise true
121 */
122 var isAllowedHttpHeader = function(header) {
123 return disableHeaderCheck || (header && forbiddenRequestHeaders.indexOf(header.toLowerCase()) === -1);
124 };
125
126 /**
127 * Check if the specified method is allowed.
128 *
129 * @param string method Request method to validate
130 * @return boolean False if not allowed, otherwise true
131 */
132 var isAllowedHttpMethod = function(method) {
133 return (method && forbiddenRequestMethods.indexOf(method) === -1);
134 };
135
136 /**
137 * Public methods
138 */
139
140 /**
141 * Open the connection. Currently supports local server requests.
142 *
143 * @param string method Connection method (eg GET, POST)
144 * @param string url URL for the connection.
145 * @param boolean async Asynchronous connection. Default is true.
146 * @param string user Username for basic authentication (optional)
147 * @param string password Password for basic authentication (optional)
148 */
149 this.open = function(method, url, async, user, password) {
150 this.abort();
151 errorFlag = false;
152
153 // Check for valid request method
154 if (!isAllowedHttpMethod(method)) {
155 throw "SecurityError: Request method not allowed";
156 }
157
158 settings = {
159 "method": method,
160 "url": url.toString(),
161 "async": (typeof async !== "boolean" ? true : async),
162 "user": user || null,
163 "password": password || null
164 };
165
166 setState(this.OPENED);
167 };
168
169 /**
170 * Disables or enables isAllowedHttpHeader() check the request. Enabled by default.
171 * This does not conform to the W3C spec.
172 *
173 * @param boolean state Enable or disable header checking.
174 */
175 this.setDisableHeaderCheck = function(state) {
176 disableHeaderCheck = state;
177 };
178
179 /**
180 * Sets a header for the request.
181 *
182 * @param string header Header name
183 * @param string value Header value
184 */
185 this.setRequestHeader = function(header, value) {
186 if (this.readyState != this.OPENED) {
187 throw "INVALID_STATE_ERR: setRequestHeader can only be called when state is OPEN";
188 }
189 if (!isAllowedHttpHeader(header)) {
190 console.warn('Refused to set unsafe header "' + header + '"');
191 return;
192 }
193 if (sendFlag) {
194 throw "INVALID_STATE_ERR: send flag is true";
195 }
196 headers[header] = value;
197 };
198
199 /**
200 * Gets a header from the server response.
201 *
202 * @param string header Name of header to get.
203 * @return string Text of the header or null if it doesn't exist.
204 */
205 this.getResponseHeader = function(header) {
206 if (typeof header === "string"
207 && this.readyState > this.OPENED
208 && response.headers[header.toLowerCase()]
209 && !errorFlag
210 ) {
211 return response.headers[header.toLowerCase()];
212 }
213
214 return null;
215 };
216
217 /**
218 * Gets all the response headers.
219 *
220 * @return string A string with all response headers separated by CR+LF
221 */
222 this.getAllResponseHeaders = function() {
223 if (this.readyState < this.HEADERS_RECEIVED || errorFlag) {
224 return "";
225 }
226 var result = "";
227
228 for (var i in response.headers) {
229 // Cookie headers are excluded
230 if (i !== "set-cookie" && i !== "set-cookie2") {
231 result += i + ": " + response.headers[i] + "\r\n";
232 }
233 }
234 return result.substr(0, result.length - 2);
235 };
236
237 /**
238 * Gets a request header
239 *
240 * @param string name Name of header to get
241 * @return string Returns the request header or empty string if not set
242 */
243 this.getRequestHeader = function(name) {
244 // @TODO Make this case insensitive
245 if (typeof name === "string" && headers[name]) {
246 return headers[name];
247 }
248
249 return "";
250 };
251
252 /**
253 * Sends the request to the server.
254 *
255 * @param string data Optional data to send as request body.
256 */
257 this.send = function(data) {
258 if (this.readyState != this.OPENED) {
259 throw "INVALID_STATE_ERR: connection must be opened before send() is called";
260 }
261
262 if (sendFlag) {
263 throw "INVALID_STATE_ERR: send has already been called";
264 }
265
266 var ssl = false, local = false;
267 var url = Url.parse(settings.url);
268 var host;
269 // Determine the server
270 switch (url.protocol) {
271 case 'https:':
272 ssl = true;
273 // SSL & non-SSL both need host, no break here.
274 case 'http:':
275 host = url.hostname;
276 break;
277
278 case 'file:':
279 local = true;
280 break;
281
282 case undefined:
283 case '':
284 host = "localhost";
285 break;
286
287 default:
288 throw "Protocol not supported.";
289 }
290
291 // Load files off the local filesystem (file://)
292 if (local) {
293 if (settings.method !== "GET") {
294 throw "XMLHttpRequest: Only GET method is supported";
295 }
296
297 if (settings.async) {
298 fs.readFile(url.pathname, 'utf8', function(error, data) {
299 if (error) {
300 self.handleError(error);
301 } else {
302 self.status = 200;
303 self.responseText = data;
304 setState(self.DONE);
305 }
306 });
307 } else {
308 try {
309 this.responseText = fs.readFileSync(url.pathname, 'utf8');
310 this.status = 200;
311 setState(self.DONE);
312 } catch(e) {
313 this.handleError(e);
314 }
315 }
316
317 return;
318 }
319
320 // Default to port 80. If accessing localhost on another port be sure
321 // to use http://localhost:port/path
322 var port = url.port || (ssl ? 443 : 80);
323 // Add query string if one is used
324 var uri = url.pathname + (url.search ? url.search : '');
325
326 // Set the Host header or the server may reject the request
327 headers["Host"] = host;
328 if (!((ssl && port === 443) || port === 80)) {
329 headers["Host"] += ':' + url.port;
330 }
331
332 // Set Basic Auth if necessary
333 if (settings.user) {
334 if (typeof settings.password == "undefined") {
335 settings.password = "";
336 }
337 var authBuf = new Buffer(settings.user + ":" + settings.password);
338 headers["Authorization"] = "Basic " + authBuf.toString("base64");
339 }
340
341 // Set content length header
342 if (settings.method === "GET" || settings.method === "HEAD") {
343 data = null;
344 } else if (data) {
345 headers["Content-Length"] = Buffer.isBuffer(data) ? data.length : Buffer.byteLength(data);
346
347 if (!headers["Content-Type"]) {
348 headers["Content-Type"] = "text/plain;charset=UTF-8";
349 }
350 } else if (settings.method === "POST") {
351 // For a post with no data set Content-Length: 0.
352 // This is required by buggy servers that don't meet the specs.
353 headers["Content-Length"] = 0;
354 }
355
356 var options = {
357 host: host,
358 port: port,
359 path: uri,
360 method: settings.method,
361 headers: headers,
362 agent: false
363 };
364
365 // Reset error flag
366 errorFlag = false;
367
368 // Handle async requests
369 if (settings.async) {
370 // Use the proper protocol
371 var doRequest = ssl ? https.request : http.request;
372
373 // Request is being sent, set send flag
374 sendFlag = true;
375
376 // As per spec, this is called here for historical reasons.
377 self.dispatchEvent("readystatechange");
378
379 // Handler for the response
380 function responseHandler(resp) {
381 // Set response var to the response we got back
382 // This is so it remains accessable outside this scope
383 response = resp;
384 // Check for redirect
385 // @TODO Prevent looped redirects
386 if (response.statusCode === 302 || response.statusCode === 303 || response.statusCode === 307) {
387 // Change URL to the redirect location
388 settings.url = response.headers.location;
389 var url = Url.parse(settings.url);
390 // Set host var in case it's used later
391 host = url.hostname;
392 // Options for the new request
393 var newOptions = {
394 hostname: url.hostname,
395 port: url.port,
396 path: url.path,
397 method: response.statusCode === 303 ? 'GET' : settings.method,
398 headers: headers
399 };
400
401 // Issue the new request
402 request = doRequest(newOptions, responseHandler).on('error', errorHandler);
403 request.end();
404 // @TODO Check if an XHR event needs to be fired here
405 return;
406 }
407
408 response.setEncoding("utf8");
409
410 setState(self.HEADERS_RECEIVED);
411 self.status = response.statusCode;
412
413 response.on('data', function(chunk) {
414 // Make sure there's some data
415 if (chunk) {
416 self.responseText += chunk;
417 }
418 // Don't emit state changes if the connection has been aborted.
419 if (sendFlag) {
420 setState(self.LOADING);
421 }
422 });
423
424 response.on('end', function() {
425 if (sendFlag) {
426 // Discard the 'end' event if the connection has been aborted
427 setState(self.DONE);
428 sendFlag = false;
429 }
430 });
431
432 response.on('error', function(error) {
433 self.handleError(error);
434 });
435 }
436
437 // Error handler for the request
438 function errorHandler(error) {
439 self.handleError(error);
440 }
441
442 // Create the request
443 request = doRequest(options, responseHandler).on('error', errorHandler);
444
445 // Node 0.4 and later won't accept empty data. Make sure it's needed.
446 if (data) {
447 request.write(data);
448 }
449
450 request.end();
451
452 self.dispatchEvent("loadstart");
453 } else { // Synchronous
454 // Create a temporary file for communication with the other Node process
455 var contentFile = ".node-xmlhttprequest-content-" + process.pid;
456 var syncFile = ".node-xmlhttprequest-sync-" + process.pid;
457 fs.writeFileSync(syncFile, "", "utf8");
458 // The async request the other Node process executes
459 var execString = "var http = require('http'), https = require('https'), fs = require('fs');"
460 + "var doRequest = http" + (ssl ? "s" : "") + ".request;"
461 + "var options = " + JSON.stringify(options) + ";"
462 + "var responseText = '';"
463 + "var req = doRequest(options, function(response) {"
464 + "response.setEncoding('utf8');"
465 + "response.on('data', function(chunk) {"
466 + " responseText += chunk;"
467 + "});"
468 + "response.on('end', function() {"
469 + "fs.writeFileSync('" + contentFile + "', 'NODE-XMLHTTPREQUEST-STATUS:' + response.statusCode + ',' + responseText, 'utf8');"
470 + "fs.unlinkSync('" + syncFile + "');"
471 + "});"
472 + "response.on('error', function(error) {"
473 + "fs.writeFileSync('" + contentFile + "', 'NODE-XMLHTTPREQUEST-ERROR:' + JSON.stringify(error), 'utf8');"
474 + "fs.unlinkSync('" + syncFile + "');"
475 + "});"
476 + "}).on('error', function(error) {"
477 + "fs.writeFileSync('" + contentFile + "', 'NODE-XMLHTTPREQUEST-ERROR:' + JSON.stringify(error), 'utf8');"
478 + "fs.unlinkSync('" + syncFile + "');"
479 + "});"
480 + (data ? "req.write('" + data.replace(/'/g, "\\'") + "');":"")
481 + "req.end();";
482 // Start the other Node Process, executing this string
483 var syncProc = spawn(process.argv[0], ["-e", execString]);
484 var statusText;
485 while(fs.existsSync(syncFile)) {
486 // Wait while the sync file is empty
487 }
488 self.responseText = fs.readFileSync(contentFile, 'utf8');
489 // Kill the child process once the file has data
490 syncProc.stdin.end();
491 // Remove the temporary file
492 fs.unlinkSync(contentFile);
493 if (self.responseText.match(/^NODE-XMLHTTPREQUEST-ERROR:/)) {
494 // If the file returned an error, handle it
495 var errorObj = self.responseText.replace(/^NODE-XMLHTTPREQUEST-ERROR:/, "");
496 self.handleError(errorObj);
497 } else {
498 // If the file returned okay, parse its data and move to the DONE state
499 self.status = self.responseText.replace(/^NODE-XMLHTTPREQUEST-STATUS:([0-9]*),.*/, "$1");
500 self.responseText = self.responseText.replace(/^NODE-XMLHTTPREQUEST-STATUS:[0-9]*,(.*)/, "$1");
501 setState(self.DONE);
502 }
503 }
504 };
505
506 /**
507 * Called when an error is encountered to deal with it.
508 */
509 this.handleError = function(error) {
510 this.status = 503;
511 this.statusText = error;
512 this.responseText = error.stack;
513 errorFlag = true;
514 setState(this.DONE);
515 };
516
517 /**
518 * Aborts a request.
519 */
520 this.abort = function() {
521 if (request) {
522 request.abort();
523 request = null;
524 }
525
526 headers = defaultHeaders;
527 this.responseText = "";
528 this.responseXML = "";
529
530 errorFlag = true;
531
532 if (this.readyState !== this.UNSENT
533 && (this.readyState !== this.OPENED || sendFlag)
534 && this.readyState !== this.DONE) {
535 sendFlag = false;
536 setState(this.DONE);
537 }
538 this.readyState = this.UNSENT;
539 };
540
541 /**
542 * Adds an event listener. Preferred method of binding to events.
543 */
544 this.addEventListener = function(event, callback) {
545 if (!(event in listeners)) {
546 listeners[event] = [];
547 }
548 // Currently allows duplicate callbacks. Should it?
549 listeners[event].push(callback);
550 };
551
552 /**
553 * Remove an event callback that has already been bound.
554 * Only works on the matching funciton, cannot be a copy.
555 */
556 this.removeEventListener = function(event, callback) {
557 if (event in listeners) {
558 // Filter will return a new array with the callback removed
559 listeners[event] = listeners[event].filter(function(ev) {
560 return ev !== callback;
561 });
562 }
563 };
564
565 /**
566 * Dispatch any events, including both "on" methods and events attached using addEventListener.
567 */
568 this.dispatchEvent = function(event) {
569 if (typeof self["on" + event] === "function") {
570 self["on" + event]();
571 }
572 if (event in listeners) {
573 for (var i = 0, len = listeners[event].length; i < len; i++) {
574 listeners[event][i].call(self);
575 }
576 }
577 };
578
579 /**
580 * Changes readyState and calls onreadystatechange.
581 *
582 * @param int state New state
583 */
584 var setState = function(state) {
585 if (self.readyState !== state) {
586 self.readyState = state;
587
588 if (settings.async || self.readyState < self.OPENED || self.readyState === self.DONE) {
589 self.dispatchEvent("readystatechange");
590 }
591
592 if (self.readyState === self.DONE && !errorFlag) {
593 self.dispatchEvent("load");
594 // @TODO figure out InspectorInstrumentation::didLoadXHR(cookie)
595 self.dispatchEvent("loadend");
596 }
597 }
598 };
599 };