SDWebImageDownloader.m
17 KB
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
/*
* This file is part of the SDWebImage package.
* (c) Olivier Poitrey <rs@dailymotion.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
#import "SDWebImageDownloader.h"
#import "SDWebImageDownloaderOperation.h"
#define LOCK(lock) dispatch_semaphore_wait(lock, DISPATCH_TIME_FOREVER);
#define UNLOCK(lock) dispatch_semaphore_signal(lock);
@interface SDWebImageDownloadToken ()
@property (nonatomic, weak, nullable) NSOperation<SDWebImageDownloaderOperationInterface> *downloadOperation;
@end
@implementation SDWebImageDownloadToken
- (void)cancel {
if (self.downloadOperation) {
SDWebImageDownloadToken *cancelToken = self.downloadOperationCancelToken;
if (cancelToken) {
[self.downloadOperation cancel:cancelToken];
}
}
}
@end
@interface SDWebImageDownloader () <NSURLSessionTaskDelegate, NSURLSessionDataDelegate>
@property (strong, nonatomic, nonnull) NSOperationQueue *downloadQueue;
@property (weak, nonatomic, nullable) NSOperation *lastAddedOperation;
@property (assign, nonatomic, nullable) Class operationClass;
@property (strong, nonatomic, nonnull) NSMutableDictionary<NSURL *, SDWebImageDownloaderOperation *> *URLOperations;
@property (strong, nonatomic, nullable) SDHTTPHeadersMutableDictionary *HTTPHeaders;
@property (strong, nonatomic, nonnull) dispatch_semaphore_t operationsLock; // a lock to keep the access to `URLOperations` thread-safe
@property (strong, nonatomic, nonnull) dispatch_semaphore_t headersLock; // a lock to keep the access to `HTTPHeaders` thread-safe
// The session in which data tasks will run
@property (strong, nonatomic) NSURLSession *session;
@end
@implementation SDWebImageDownloader
+ (void)initialize {
// Bind SDNetworkActivityIndicator if available (download it here: http://github.com/rs/SDNetworkActivityIndicator )
// To use it, just add #import "SDNetworkActivityIndicator.h" in addition to the SDWebImage import
if (NSClassFromString(@"SDNetworkActivityIndicator")) {
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Warc-performSelector-leaks"
id activityIndicator = [NSClassFromString(@"SDNetworkActivityIndicator") performSelector:NSSelectorFromString(@"sharedActivityIndicator")];
#pragma clang diagnostic pop
// Remove observer in case it was previously added.
[[NSNotificationCenter defaultCenter] removeObserver:activityIndicator name:SDWebImageDownloadStartNotification object:nil];
[[NSNotificationCenter defaultCenter] removeObserver:activityIndicator name:SDWebImageDownloadStopNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:activityIndicator
selector:NSSelectorFromString(@"startActivity")
name:SDWebImageDownloadStartNotification object:nil];
[[NSNotificationCenter defaultCenter] addObserver:activityIndicator
selector:NSSelectorFromString(@"stopActivity")
name:SDWebImageDownloadStopNotification object:nil];
}
}
+ (nonnull instancetype)sharedDownloader {
static dispatch_once_t once;
static id instance;
dispatch_once(&once, ^{
instance = [self new];
});
return instance;
}
- (nonnull instancetype)init {
return [self initWithSessionConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration]];
}
- (nonnull instancetype)initWithSessionConfiguration:(nullable NSURLSessionConfiguration *)sessionConfiguration {
if ((self = [super init])) {
_operationClass = [SDWebImageDownloaderOperation class];
_shouldDecompressImages = YES;
_executionOrder = SDWebImageDownloaderFIFOExecutionOrder;
_downloadQueue = [NSOperationQueue new];
_downloadQueue.maxConcurrentOperationCount = 6;
_downloadQueue.name = @"com.hackemist.SDWebImageDownloader";
_URLOperations = [NSMutableDictionary new];
#ifdef SD_WEBP
_HTTPHeaders = [@{@"Accept": @"image/webp,image/*;q=0.8"} mutableCopy];
#else
_HTTPHeaders = [@{@"Accept": @"image/*;q=0.8"} mutableCopy];
#endif
_operationsLock = dispatch_semaphore_create(1);
_headersLock = dispatch_semaphore_create(1);
_downloadTimeout = 15.0;
[self createNewSessionWithConfiguration:sessionConfiguration];
}
return self;
}
- (void)createNewSessionWithConfiguration:(NSURLSessionConfiguration *)sessionConfiguration {
[self cancelAllDownloads];
if (self.session) {
[self.session invalidateAndCancel];
}
sessionConfiguration.timeoutIntervalForRequest = self.downloadTimeout;
/**
* Create the session for this task
* We send nil as delegate queue so that the session creates a serial operation queue for performing all delegate
* method calls and completion handler calls.
*/
self.session = [NSURLSession sessionWithConfiguration:sessionConfiguration
delegate:self
delegateQueue:nil];
}
- (void)invalidateSessionAndCancel:(BOOL)cancelPendingOperations {
if (self == [SDWebImageDownloader sharedDownloader]) {
return;
}
if (cancelPendingOperations) {
[self.session invalidateAndCancel];
} else {
[self.session finishTasksAndInvalidate];
}
}
- (void)dealloc {
[self.session invalidateAndCancel];
self.session = nil;
[self.downloadQueue cancelAllOperations];
}
- (void)setValue:(nullable NSString *)value forHTTPHeaderField:(nullable NSString *)field {
LOCK(self.headersLock);
if (value) {
self.HTTPHeaders[field] = value;
} else {
[self.HTTPHeaders removeObjectForKey:field];
}
UNLOCK(self.headersLock);
}
- (nullable NSString *)valueForHTTPHeaderField:(nullable NSString *)field {
if (!field) {
return nil;
}
return [[self allHTTPHeaderFields] objectForKey:field];
}
- (nonnull SDHTTPHeadersDictionary *)allHTTPHeaderFields {
LOCK(self.headersLock);
SDHTTPHeadersDictionary *allHTTPHeaderFields = [self.HTTPHeaders copy];
UNLOCK(self.headersLock);
return allHTTPHeaderFields;
}
- (void)setMaxConcurrentDownloads:(NSInteger)maxConcurrentDownloads {
_downloadQueue.maxConcurrentOperationCount = maxConcurrentDownloads;
}
- (NSUInteger)currentDownloadCount {
return _downloadQueue.operationCount;
}
- (NSInteger)maxConcurrentDownloads {
return _downloadQueue.maxConcurrentOperationCount;
}
- (NSURLSessionConfiguration *)sessionConfiguration {
return self.session.configuration;
}
- (void)setOperationClass:(nullable Class)operationClass {
if (operationClass && [operationClass isSubclassOfClass:[NSOperation class]] && [operationClass conformsToProtocol:@protocol(SDWebImageDownloaderOperationInterface)]) {
_operationClass = operationClass;
} else {
_operationClass = [SDWebImageDownloaderOperation class];
}
}
- (nullable SDWebImageDownloadToken *)downloadImageWithURL:(nullable NSURL *)url
options:(SDWebImageDownloaderOptions)options
progress:(nullable SDWebImageDownloaderProgressBlock)progressBlock
completed:(nullable SDWebImageDownloaderCompletedBlock)completedBlock {
__weak SDWebImageDownloader *wself = self;
return [self addProgressCallback:progressBlock completedBlock:completedBlock forURL:url createCallback:^SDWebImageDownloaderOperation *{
__strong __typeof (wself) sself = wself;
NSTimeInterval timeoutInterval = sself.downloadTimeout;
if (timeoutInterval == 0.0) {
timeoutInterval = 15.0;
}
// In order to prevent from potential duplicate caching (NSURLCache + SDImageCache) we disable the cache for image requests if told otherwise
NSURLRequestCachePolicy cachePolicy = options & SDWebImageDownloaderUseNSURLCache ? NSURLRequestUseProtocolCachePolicy : NSURLRequestReloadIgnoringLocalCacheData;
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] initWithURL:url
cachePolicy:cachePolicy
timeoutInterval:timeoutInterval];
request.HTTPShouldHandleCookies = (options & SDWebImageDownloaderHandleCookies);
request.HTTPShouldUsePipelining = YES;
if (sself.headersFilter) {
request.allHTTPHeaderFields = sself.headersFilter(url, [sself allHTTPHeaderFields]);
}
else {
request.allHTTPHeaderFields = [sself allHTTPHeaderFields];
}
SDWebImageDownloaderOperation *operation = [[sself.operationClass alloc] initWithRequest:request inSession:sself.session options:options];
operation.shouldDecompressImages = sself.shouldDecompressImages;
if (sself.urlCredential) {
operation.credential = sself.urlCredential;
} else if (sself.username && sself.password) {
operation.credential = [NSURLCredential credentialWithUser:sself.username password:sself.password persistence:NSURLCredentialPersistenceForSession];
}
if (options & SDWebImageDownloaderHighPriority) {
operation.queuePriority = NSOperationQueuePriorityHigh;
} else if (options & SDWebImageDownloaderLowPriority) {
operation.queuePriority = NSOperationQueuePriorityLow;
}
if (sself.executionOrder == SDWebImageDownloaderLIFOExecutionOrder) {
// Emulate LIFO execution order by systematically adding new operations as last operation's dependency
[sself.lastAddedOperation addDependency:operation];
sself.lastAddedOperation = operation;
}
return operation;
}];
}
- (void)cancel:(nullable SDWebImageDownloadToken *)token {
NSURL *url = token.url;
if (!url) {
return;
}
LOCK(self.operationsLock);
SDWebImageDownloaderOperation *operation = [self.URLOperations objectForKey:url];
if (operation) {
BOOL canceled = [operation cancel:token.downloadOperationCancelToken];
if (canceled) {
[self.URLOperations removeObjectForKey:url];
}
}
UNLOCK(self.operationsLock);
}
- (nullable SDWebImageDownloadToken *)addProgressCallback:(SDWebImageDownloaderProgressBlock)progressBlock
completedBlock:(SDWebImageDownloaderCompletedBlock)completedBlock
forURL:(nullable NSURL *)url
createCallback:(SDWebImageDownloaderOperation *(^)(void))createCallback {
// The URL will be used as the key to the callbacks dictionary so it cannot be nil. If it is nil immediately call the completed block with no image or data.
if (url == nil) {
if (completedBlock != nil) {
completedBlock(nil, nil, nil, NO);
}
return nil;
}
LOCK(self.operationsLock);
SDWebImageDownloaderOperation *operation = [self.URLOperations objectForKey:url];
// There is a case that the operation may be marked as finished, but not been removed from `self.URLOperations`.
if (!operation || operation.isFinished) {
operation = createCallback();
__weak typeof(self) wself = self;
operation.completionBlock = ^{
__strong typeof(wself) sself = wself;
if (!sself) {
return;
}
LOCK(sself.operationsLock);
[sself.URLOperations removeObjectForKey:url];
UNLOCK(sself.operationsLock);
};
[self.URLOperations setObject:operation forKey:url];
// Add operation to operation queue only after all configuration done according to Apple's doc.
// `addOperation:` does not synchronously execute the `operation.completionBlock` so this will not cause deadlock.
[self.downloadQueue addOperation:operation];
}
UNLOCK(self.operationsLock);
id downloadOperationCancelToken = [operation addHandlersForProgress:progressBlock completed:completedBlock];
SDWebImageDownloadToken *token = [SDWebImageDownloadToken new];
token.downloadOperation = operation;
token.url = url;
token.downloadOperationCancelToken = downloadOperationCancelToken;
return token;
}
- (void)setSuspended:(BOOL)suspended {
self.downloadQueue.suspended = suspended;
}
- (void)cancelAllDownloads {
[self.downloadQueue cancelAllOperations];
}
#pragma mark Helper methods
- (SDWebImageDownloaderOperation *)operationWithTask:(NSURLSessionTask *)task {
SDWebImageDownloaderOperation *returnOperation = nil;
for (SDWebImageDownloaderOperation *operation in self.downloadQueue.operations) {
if (operation.dataTask.taskIdentifier == task.taskIdentifier) {
returnOperation = operation;
break;
}
}
return returnOperation;
}
#pragma mark NSURLSessionDataDelegate
- (void)URLSession:(NSURLSession *)session
dataTask:(NSURLSessionDataTask *)dataTask
didReceiveResponse:(NSURLResponse *)response
completionHandler:(void (^)(NSURLSessionResponseDisposition disposition))completionHandler {
// Identify the operation that runs this task and pass it the delegate method
SDWebImageDownloaderOperation *dataOperation = [self operationWithTask:dataTask];
if ([dataOperation respondsToSelector:@selector(URLSession:dataTask:didReceiveResponse:completionHandler:)]) {
[dataOperation URLSession:session dataTask:dataTask didReceiveResponse:response completionHandler:completionHandler];
} else {
if (completionHandler) {
completionHandler(NSURLSessionResponseAllow);
}
}
}
- (void)URLSession:(NSURLSession *)session dataTask:(NSURLSessionDataTask *)dataTask didReceiveData:(NSData *)data {
// Identify the operation that runs this task and pass it the delegate method
SDWebImageDownloaderOperation *dataOperation = [self operationWithTask:dataTask];
if ([dataOperation respondsToSelector:@selector(URLSession:dataTask:didReceiveData:)]) {
[dataOperation URLSession:session dataTask:dataTask didReceiveData:data];
}
}
- (void)URLSession:(NSURLSession *)session
dataTask:(NSURLSessionDataTask *)dataTask
willCacheResponse:(NSCachedURLResponse *)proposedResponse
completionHandler:(void (^)(NSCachedURLResponse *cachedResponse))completionHandler {
// Identify the operation that runs this task and pass it the delegate method
SDWebImageDownloaderOperation *dataOperation = [self operationWithTask:dataTask];
if ([dataOperation respondsToSelector:@selector(URLSession:dataTask:willCacheResponse:completionHandler:)]) {
[dataOperation URLSession:session dataTask:dataTask willCacheResponse:proposedResponse completionHandler:completionHandler];
} else {
if (completionHandler) {
completionHandler(proposedResponse);
}
}
}
#pragma mark NSURLSessionTaskDelegate
- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error {
// Identify the operation that runs this task and pass it the delegate method
SDWebImageDownloaderOperation *dataOperation = [self operationWithTask:task];
if ([dataOperation respondsToSelector:@selector(URLSession:task:didCompleteWithError:)]) {
[dataOperation URLSession:session task:task didCompleteWithError:error];
}
}
- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task willPerformHTTPRedirection:(NSHTTPURLResponse *)response newRequest:(NSURLRequest *)request completionHandler:(void (^)(NSURLRequest * _Nullable))completionHandler {
// Identify the operation that runs this task and pass it the delegate method
SDWebImageDownloaderOperation *dataOperation = [self operationWithTask:task];
if ([dataOperation respondsToSelector:@selector(URLSession:task:willPerformHTTPRedirection:newRequest:completionHandler:)]) {
[dataOperation URLSession:session task:task willPerformHTTPRedirection:response newRequest:request completionHandler:completionHandler];
} else {
if (completionHandler) {
completionHandler(request);
}
}
}
- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didReceiveChallenge:(NSURLAuthenticationChallenge *)challenge completionHandler:(void (^)(NSURLSessionAuthChallengeDisposition disposition, NSURLCredential *credential))completionHandler {
// Identify the operation that runs this task and pass it the delegate method
SDWebImageDownloaderOperation *dataOperation = [self operationWithTask:task];
if ([dataOperation respondsToSelector:@selector(URLSession:task:didReceiveChallenge:completionHandler:)]) {
[dataOperation URLSession:session task:task didReceiveChallenge:challenge completionHandler:completionHandler];
} else {
if (completionHandler) {
completionHandler(NSURLSessionAuthChallengePerformDefaultHandling, nil);
}
}
}
@end