/
ajax.ts
619 lines (554 loc) · 21.6 KB
/
ajax.ts
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
import { map } from '../operators/map';
import { Observable } from '../Observable';
import { AjaxConfig, AjaxRequest, AjaxDirection, ProgressEventType } from './types';
import { AjaxResponse } from './AjaxResponse';
import { AjaxTimeoutError, AjaxError } from './errors';
export interface AjaxCreationMethod {
/**
* Creates an observable that will perform an AJAX request using the
* [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest) in
* global scope by default.
*
* This is the most configurable option, and the basis for all other AJAX calls in the library.
*
* ## Example
*
* ```ts
* import { ajax } from 'rxjs/ajax';
* import { map, catchError, of } from 'rxjs';
*
* const obs$ = ajax({
* method: 'GET',
* url: 'https://api.github.com/users?per_page=5',
* responseType: 'json',
* }).pipe(
* map(userResponse => console.log('users: ', userResponse)),
* catchError(error => {
* console.log('error: ', error);
* return of(error);
* })
* );
* ```
*/
<T>(config: AjaxConfig): Observable<AjaxResponse<T>>;
/**
* Perform an HTTP GET using the
* [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest) in
* global scope. Defaults to a `responseType` of `"json"`.
*
* ## Example
*
* ```ts
* import { ajax } from 'rxjs/ajax';
* import { map, catchError, of } from 'rxjs';
*
* const obs$ = ajax('https://api.github.com/users?per_page=5').pipe(
* map(userResponse => console.log('users: ', userResponse)),
* catchError(error => {
* console.log('error: ', error);
* return of(error);
* })
* );
* ```
*/
<T>(url: string): Observable<AjaxResponse<T>>;
/**
* Performs an HTTP GET using the
* [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest) in
* global scope by default, and a `responseType` of `"json"`.
*
* @param url The URL to get the resource from
* @param headers Optional headers. Case-Insensitive.
*/
get<T>(url: string, headers?: Record<string, string>): Observable<AjaxResponse<T>>;
/**
* Performs an HTTP POST using the
* [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest) in
* global scope by default, and a `responseType` of `"json"`.
*
* Before sending the value passed to the `body` argument, it is automatically serialized
* based on the specified `responseType`. By default, a JavaScript object will be serialized
* to JSON. A `responseType` of `application/x-www-form-urlencoded` will flatten any provided
* dictionary object to a url-encoded string.
*
* @param url The URL to get the resource from
* @param body The content to send. The body is automatically serialized.
* @param headers Optional headers. Case-Insensitive.
*/
post<T>(url: string, body?: any, headers?: Record<string, string>): Observable<AjaxResponse<T>>;
/**
* Performs an HTTP PUT using the
* [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest) in
* global scope by default, and a `responseType` of `"json"`.
*
* Before sending the value passed to the `body` argument, it is automatically serialized
* based on the specified `responseType`. By default, a JavaScript object will be serialized
* to JSON. A `responseType` of `application/x-www-form-urlencoded` will flatten any provided
* dictionary object to a url-encoded string.
*
* @param url The URL to get the resource from
* @param body The content to send. The body is automatically serialized.
* @param headers Optional headers. Case-Insensitive.
*/
put<T>(url: string, body?: any, headers?: Record<string, string>): Observable<AjaxResponse<T>>;
/**
* Performs an HTTP PATCH using the
* [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest) in
* global scope by default, and a `responseType` of `"json"`.
*
* Before sending the value passed to the `body` argument, it is automatically serialized
* based on the specified `responseType`. By default, a JavaScript object will be serialized
* to JSON. A `responseType` of `application/x-www-form-urlencoded` will flatten any provided
* dictionary object to a url-encoded string.
*
* @param url The URL to get the resource from
* @param body The content to send. The body is automatically serialized.
* @param headers Optional headers. Case-Insensitive.
*/
patch<T>(url: string, body?: any, headers?: Record<string, string>): Observable<AjaxResponse<T>>;
/**
* Performs an HTTP DELETE using the
* [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest) in
* global scope by default, and a `responseType` of `"json"`.
*
* @param url The URL to get the resource from
* @param headers Optional headers. Case-Insensitive.
*/
delete<T>(url: string, headers?: Record<string, string>): Observable<AjaxResponse<T>>;
/**
* Performs an HTTP GET using the
* [XMLHttpRequest](https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest) in
* global scope by default, and returns the hydrated JavaScript object from the
* response.
*
* @param url The URL to get the resource from
* @param headers Optional headers. Case-Insensitive.
*/
getJSON<T>(url: string, headers?: Record<string, string>): Observable<T>;
}
function ajaxGet<T>(url: string, headers?: Record<string, string>): Observable<AjaxResponse<T>> {
return ajax({ method: 'GET', url, headers });
}
function ajaxPost<T>(url: string, body?: any, headers?: Record<string, string>): Observable<AjaxResponse<T>> {
return ajax({ method: 'POST', url, body, headers });
}
function ajaxDelete<T>(url: string, headers?: Record<string, string>): Observable<AjaxResponse<T>> {
return ajax({ method: 'DELETE', url, headers });
}
function ajaxPut<T>(url: string, body?: any, headers?: Record<string, string>): Observable<AjaxResponse<T>> {
return ajax({ method: 'PUT', url, body, headers });
}
function ajaxPatch<T>(url: string, body?: any, headers?: Record<string, string>): Observable<AjaxResponse<T>> {
return ajax({ method: 'PATCH', url, body, headers });
}
const mapResponse = map((x: AjaxResponse<any>) => x.response);
function ajaxGetJSON<T>(url: string, headers?: Record<string, string>): Observable<T> {
return mapResponse(
ajax<T>({
method: 'GET',
url,
headers,
})
);
}
/**
* There is an ajax operator on the Rx object.
*
* It creates an observable for an Ajax request with either a request object with
* url, headers, etc or a string for a URL.
*
* ## Examples
*
* Using `ajax()` to fetch the response object that is being returned from API
*
* ```ts
* import { ajax } from 'rxjs/ajax';
* import { map, catchError, of } from 'rxjs';
*
* const obs$ = ajax('https://api.github.com/users?per_page=5').pipe(
* map(userResponse => console.log('users: ', userResponse)),
* catchError(error => {
* console.log('error: ', error);
* return of(error);
* })
* );
*
* obs$.subscribe({
* next: value => console.log(value),
* error: err => console.log(err),
* });
* ```
*
* Using `ajax.getJSON()` to fetch data from API
*
* ```ts
* import { ajax } from 'rxjs/ajax';
* import { map, catchError, of } from 'rxjs';
*
* const obs$ = ajax.getJSON('https://api.github.com/users?per_page=5').pipe(
* map(userResponse => console.log('users: ', userResponse)),
* catchError(error => {
* console.log('error: ', error);
* return of(error);
* })
* );
*
* obs$.subscribe({
* next: value => console.log(value),
* error: err => console.log(err),
* });
* ```
*
* Using `ajax()` with object as argument and method POST with a two seconds delay
*
* ```ts
* import { ajax } from 'rxjs/ajax';
* import { map, catchError, of } from 'rxjs';
*
* const users = ajax({
* url: 'https://httpbin.org/delay/2',
* method: 'POST',
* headers: {
* 'Content-Type': 'application/json',
* 'rxjs-custom-header': 'Rxjs'
* },
* body: {
* rxjs: 'Hello World!'
* }
* }).pipe(
* map(response => console.log('response: ', response)),
* catchError(error => {
* console.log('error: ', error);
* return of(error);
* })
* );
*
* users.subscribe({
* next: value => console.log(value),
* error: err => console.log(err),
* });
* ```
*
* Using ajax() to fetch. An error object that is being returned from the request
*
* ```ts
* import { ajax } from 'rxjs/ajax';
* import { map, catchError, of } from 'rxjs';
*
* const obs$ = ajax('https://api.github.com/404').pipe(
* map(userResponse => console.log('users: ', userResponse)),
* catchError(error => {
* console.log('error: ', error);
* return of(error);
* })
* );
*
* obs$.subscribe({
* next: value => console.log(value),
* error: err => console.log(err),
* });
* ```
*/
export const ajax: AjaxCreationMethod = (() => {
const create = <T>(urlOrConfig: string | AjaxConfig) => {
const config: AjaxConfig =
typeof urlOrConfig === 'string'
? {
url: urlOrConfig,
}
: urlOrConfig;
return fromAjax<T>(config);
};
create.get = ajaxGet;
create.post = ajaxPost;
create.delete = ajaxDelete;
create.put = ajaxPut;
create.patch = ajaxPatch;
create.getJSON = ajaxGetJSON;
return create;
})();
const UPLOAD = 'upload';
const DOWNLOAD = 'download';
const LOADSTART = 'loadstart';
const PROGRESS = 'progress';
const LOAD = 'load';
export function fromAjax<T>(config: AjaxConfig): Observable<AjaxResponse<T>> {
return new Observable((destination) => {
// Here we're pulling off each of the configuration arguments
// that we don't want to add to the request information we're
// passing around.
const { queryParams, body: configuredBody, headers: configuredHeaders, ...remainingConfig } = config;
let { url } = remainingConfig;
if (!url) {
throw new TypeError('url is required');
}
if (queryParams) {
let searchParams: URLSearchParams;
if (url.includes('?')) {
// If the user has passed a URL with a querystring already in it,
// we need to combine them. So we're going to split it. There
// should only be one `?` in a valid URL.
const parts = url.split('?');
if (2 < parts.length) {
throw new TypeError('invalid url');
}
// Add the passed queryParams to the params already in the url provided.
searchParams = new URLSearchParams(parts[1]);
// queryParams is converted to any because the runtime is *much* more permissive than
// the types are.
new URLSearchParams(queryParams as any).forEach((value, key) => searchParams.set(key, value));
// We have to do string concatenation here, because `new URL(url)` does
// not like relative URLs like `/this` without a base url, which we can't
// specify, nor can we assume `location` will exist, because of node.
url = parts[0] + '?' + searchParams;
} else {
// There is no pre-existing querystring, so we can just use URLSearchParams
// to convert the passed queryParams into the proper format and encodings.
// queryParams is converted to any because the runtime is *much* more permissive than
// the types are.
searchParams = new URLSearchParams(queryParams as any);
url = url + '?' + searchParams;
}
}
// Normalize the headers. We're going to make them all lowercase, since
// Headers are case insensitive by design. This makes it easier to verify
// that we aren't setting or sending duplicates.
const headers: Record<string, any> = {};
if (configuredHeaders) {
for (const key in configuredHeaders) {
if (configuredHeaders.hasOwnProperty(key)) {
headers[key.toLowerCase()] = configuredHeaders[key];
}
}
}
// Set the x-requested-with header. This is a non-standard header that has
// come to be a de facto standard for HTTP requests sent by libraries and frameworks
// using XHR. However, we DO NOT want to set this if it is a CORS request. This is
// because sometimes this header can cause issues with CORS. To be clear,
// None of this is necessary, it's only being set because it's "the thing libraries do"
// Starting back as far as JQuery, and continuing with other libraries such as Angular 1,
// Axios, et al.
if (!config.crossDomain && !('x-requested-with' in headers)) {
headers['x-requested-with'] = 'XMLHttpRequest';
}
// Allow users to provide their XSRF cookie name and the name of a custom header to use to
// send the cookie.
const { withCredentials, xsrfCookieName, xsrfHeaderName } = remainingConfig;
if ((withCredentials || !remainingConfig.crossDomain) && xsrfCookieName && xsrfHeaderName) {
const xsrfCookie = document?.cookie.match(new RegExp(`(^|;\\s*)(${xsrfCookieName})=([^;]*)`))?.pop() ?? '';
if (xsrfCookie) {
headers[xsrfHeaderName] = xsrfCookie;
}
}
// Examine the body and determine whether or not to serialize it
// and set the content-type in `headers`, if we're able.
const body = extractContentTypeAndMaybeSerializeBody(configuredBody, headers);
const _request: AjaxRequest = {
// Default values
async: true,
crossDomain: true,
withCredentials: false,
method: 'GET',
timeout: 0,
responseType: 'json' as XMLHttpRequestResponseType,
// Override with passed user values
...remainingConfig,
// Set values we ensured above
url,
headers,
body,
};
let xhr: XMLHttpRequest;
// Create our XHR so we can get started.
xhr = config.createXHR ? config.createXHR() : new XMLHttpRequest();
{
///////////////////////////////////////////////////
// set up the events before open XHR
// https://developer.mozilla.org/en/docs/Web/API/XMLHttpRequest/Using_XMLHttpRequest
// You need to add the event listeners before calling open() on the request.
// Otherwise the progress events will not fire.
///////////////////////////////////////////////////
const { progressSubscriber, includeDownloadProgress = false, includeUploadProgress = false } = config;
/**
* Wires up an event handler that will emit an error when fired. Used
* for timeout and abort events.
* @param type The type of event we're treating as an error
* @param errorFactory A function that creates the type of error to emit.
*/
const addErrorEvent = (type: string, errorFactory: () => any) => {
xhr.addEventListener(type, () => {
const error = errorFactory();
progressSubscriber?.error?.(error);
destination.error(error);
});
};
// If the request times out, handle errors appropriately.
addErrorEvent('timeout', () => new AjaxTimeoutError(xhr, _request));
// If the request aborts (due to a network disconnection or the like), handle
// it as an error.
addErrorEvent('abort', () => new AjaxError('aborted', xhr, _request));
/**
* Creates a response object to emit to the consumer.
* @param direction the direction related to the event. Prefixes the event `type` in the
* `AjaxResponse` object with "upload_" for events related to uploading and "download_"
* for events related to downloading.
* @param event the actual event object.
*/
const createResponse = (direction: AjaxDirection, event: ProgressEvent) =>
new AjaxResponse<T>(event, xhr, _request, `${direction}_${event.type as ProgressEventType}` as const);
/**
* Wires up an event handler that emits a Response object to the consumer, used for
* all events that emit responses, loadstart, progress, and load.
* Note that download load handling is a bit different below, because it has
* more logic it needs to run.
* @param target The target, either the XHR itself or the Upload object.
* @param type The type of event to wire up
* @param direction The "direction", used to prefix the response object that is
* emitted to the consumer. (e.g. "upload_" or "download_")
*/
const addProgressEvent = (target: any, type: string, direction: AjaxDirection) => {
target.addEventListener(type, (event: ProgressEvent) => {
destination.next(createResponse(direction, event));
});
};
if (includeUploadProgress) {
[LOADSTART, PROGRESS, LOAD].forEach((type) => addProgressEvent(xhr.upload, type, UPLOAD));
}
if (progressSubscriber) {
[LOADSTART, PROGRESS].forEach((type) => xhr.upload.addEventListener(type, (e: any) => progressSubscriber?.next?.(e)));
}
if (includeDownloadProgress) {
[LOADSTART, PROGRESS].forEach((type) => addProgressEvent(xhr, type, DOWNLOAD));
}
const emitError = (status?: number) => {
const msg = 'ajax error' + (status ? ' ' + status : '');
destination.error(new AjaxError(msg, xhr, _request));
};
xhr.addEventListener('error', (e) => {
progressSubscriber?.error?.(e);
emitError();
});
xhr.addEventListener(LOAD, (event) => {
const { status } = xhr;
// 4xx and 5xx should error (https://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html)
if (status < 400) {
progressSubscriber?.complete?.();
let response: AjaxResponse<T>;
try {
// This can throw in IE, because we end up needing to do a JSON.parse
// of the response in some cases to produce object we'd expect from
// modern browsers.
response = createResponse(DOWNLOAD, event);
} catch (err) {
destination.error(err);
return;
}
destination.next(response);
destination.complete();
} else {
progressSubscriber?.error?.(event);
emitError(status);
}
});
}
const { user, method, async } = _request;
// open XHR
if (user) {
xhr.open(method, url, async, user, _request.password);
} else {
xhr.open(method, url, async);
}
// timeout, responseType and withCredentials can be set once the XHR is open
if (async) {
xhr.timeout = _request.timeout;
xhr.responseType = _request.responseType;
}
if ('withCredentials' in xhr) {
xhr.withCredentials = _request.withCredentials;
}
// set headers
for (const key in headers) {
if (headers.hasOwnProperty(key)) {
xhr.setRequestHeader(key, headers[key]);
}
}
// finally send the request
if (body) {
xhr.send(body);
} else {
xhr.send();
}
return () => {
if (xhr && xhr.readyState !== 4 /*XHR done*/) {
xhr.abort();
}
};
});
}
/**
* Examines the body to determine if we need to serialize it for them or not.
* If the body is a type that XHR handles natively, we just allow it through,
* otherwise, if the body is something that *we* can serialize for the user,
* we will serialize it, and attempt to set the `content-type` header, if it's
* not already set.
* @param body The body passed in by the user
* @param headers The normalized headers
*/
function extractContentTypeAndMaybeSerializeBody(body: any, headers: Record<string, string>) {
if (
!body ||
typeof body === 'string' ||
isFormData(body) ||
isURLSearchParams(body) ||
isArrayBuffer(body) ||
isFile(body) ||
isBlob(body) ||
isReadableStream(body)
) {
// The XHR instance itself can handle serializing these, and set the content-type for us
// so we don't need to do that. https://xhr.spec.whatwg.org/#the-send()-method
return body;
}
if (isArrayBufferView(body)) {
// This is a typed array (e.g. Float32Array or Uint8Array), or a DataView.
// XHR can handle this one too: https://fetch.spec.whatwg.org/#concept-bodyinit-extract
return body.buffer;
}
if (typeof body === 'object') {
// If we have made it here, this is an object, probably a POJO, and we'll try
// to serialize it for them. If this doesn't work, it will throw, obviously, which
// is okay. The workaround for users would be to manually set the body to their own
// serialized string (accounting for circular references or whatever), then set
// the content-type manually as well.
headers['content-type'] = headers['content-type'] ?? 'application/json;charset=utf-8';
return JSON.stringify(body);
}
// If we've gotten past everything above, this is something we don't quite know how to
// handle. Throw an error. This will be caught and emitted from the observable.
throw new TypeError('Unknown body type');
}
const _toString = Object.prototype.toString;
function toStringCheck(obj: any, name: string): boolean {
return _toString.call(obj) === `[object ${name}]`;
}
function isArrayBuffer(body: any): body is ArrayBuffer {
return toStringCheck(body, 'ArrayBuffer');
}
function isFile(body: any): body is File {
return toStringCheck(body, 'File');
}
function isBlob(body: any): body is Blob {
return toStringCheck(body, 'Blob');
}
function isArrayBufferView(body: any): body is ArrayBufferView {
return typeof ArrayBuffer !== 'undefined' && ArrayBuffer.isView(body);
}
function isFormData(body: any): body is FormData {
return typeof FormData !== 'undefined' && body instanceof FormData;
}
function isURLSearchParams(body: any): body is URLSearchParams {
return typeof URLSearchParams !== 'undefined' && body instanceof URLSearchParams;
}
function isReadableStream(body: any): body is ReadableStream {
return typeof ReadableStream !== 'undefined' && body instanceof ReadableStream;
}