/** * Copyright (c) 2015-present, Facebook, Inc. * All rights reserved. * * This source code is licensed under the BSD-style license found in the * LICENSE file in the root directory of this source tree. An additional grant * of patent rights can be found in the PATENTS file in the same directory. */ #import "RCTImageLoader.h" #import #import #import #import "RCTConvert.h" #import "RCTDefines.h" #import "RCTImageUtils.h" #import "RCTLog.h" #import "RCTNetworking.h" #import "RCTUtils.h" static NSString *const RCTErrorInvalidURI = @"E_INVALID_URI"; static NSString *const RCTErrorPrefetchFailure = @"E_PREFETCH_FAILURE"; @implementation UIImage (React) - (CAKeyframeAnimation *)reactKeyframeAnimation { return objc_getAssociatedObject(self, _cmd); } - (void)setReactKeyframeAnimation:(CAKeyframeAnimation *)reactKeyframeAnimation { objc_setAssociatedObject(self, @selector(reactKeyframeAnimation), reactKeyframeAnimation, OBJC_ASSOCIATION_COPY_NONATOMIC); } @end @implementation RCTImageLoader { NSArray> *_loaders; NSArray> *_decoders; NSOperationQueue *_imageDecodeQueue; dispatch_queue_t _URLCacheQueue; NSURLCache *_URLCache; NSMutableArray *_pendingTasks; NSInteger _activeTasks; NSMutableArray *_pendingDecodes; NSInteger _scheduledDecodes; NSUInteger _activeBytes; } @synthesize bridge = _bridge; RCT_EXPORT_MODULE() - (void)setUp { // Set defaults _maxConcurrentLoadingTasks = _maxConcurrentLoadingTasks ?: 4; _maxConcurrentDecodingTasks = _maxConcurrentDecodingTasks ?: 2; _maxConcurrentDecodingBytes = _maxConcurrentDecodingBytes ?: 30 * 1024 *1024; // 30MB _URLCacheQueue = dispatch_queue_create("com.facebook.react.ImageLoaderURLCacheQueue", DISPATCH_QUEUE_SERIAL); } - (id)imageURLLoaderForURL:(NSURL *)URL { if (!_maxConcurrentLoadingTasks) { [self setUp]; } if (!_loaders) { // Get loaders, sorted in reverse priority order (highest priority first) RCTAssert(_bridge, @"Bridge not set"); _loaders = [[_bridge modulesConformingToProtocol:@protocol(RCTImageURLLoader)] sortedArrayUsingComparator:^NSComparisonResult(id a, id b) { float priorityA = [a respondsToSelector:@selector(loaderPriority)] ? [a loaderPriority] : 0; float priorityB = [b respondsToSelector:@selector(loaderPriority)] ? [b loaderPriority] : 0; if (priorityA > priorityB) { return NSOrderedAscending; } else if (priorityA < priorityB) { return NSOrderedDescending; } else { return NSOrderedSame; } }]; } if (RCT_DEBUG) { // Check for handler conflicts float previousPriority = 0; id previousLoader = nil; for (id loader in _loaders) { float priority = [loader respondsToSelector:@selector(loaderPriority)] ? [loader loaderPriority] : 0; if (previousLoader && priority < previousPriority) { return previousLoader; } if ([loader canLoadImageURL:URL]) { if (previousLoader) { if (priority == previousPriority) { RCTLogError(@"The RCTImageURLLoaders %@ and %@ both reported that" " they can load the URL %@, and have equal priority" " (%g). This could result in non-deterministic behavior.", loader, previousLoader, URL, priority); } } else { previousLoader = loader; previousPriority = priority; } } } return previousLoader; } // Normal code path for (id loader in _loaders) { if ([loader canLoadImageURL:URL]) { return loader; } } return nil; } - (id)imageDataDecoderForData:(NSData *)data { if (!_maxConcurrentLoadingTasks) { [self setUp]; } if (!_decoders) { // Get decoders, sorted in reverse priority order (highest priority first) RCTAssert(_bridge, @"Bridge not set"); _decoders = [[_bridge modulesConformingToProtocol:@protocol(RCTImageDataDecoder)] sortedArrayUsingComparator:^NSComparisonResult(id a, id b) { float priorityA = [a respondsToSelector:@selector(decoderPriority)] ? [a decoderPriority] : 0; float priorityB = [b respondsToSelector:@selector(decoderPriority)] ? [b decoderPriority] : 0; if (priorityA > priorityB) { return NSOrderedAscending; } else if (priorityA < priorityB) { return NSOrderedDescending; } else { return NSOrderedSame; } }]; } if (RCT_DEBUG) { // Check for handler conflicts float previousPriority = 0; id previousDecoder = nil; for (id decoder in _decoders) { float priority = [decoder respondsToSelector:@selector(decoderPriority)] ? [decoder decoderPriority] : 0; if (previousDecoder && priority < previousPriority) { return previousDecoder; } if ([decoder canDecodeImageData:data]) { if (previousDecoder) { if (priority == previousPriority) { RCTLogError(@"The RCTImageDataDecoders %@ and %@ both reported that" " they can decode the data , and" " have equal priority (%g). This could result in" " non-deterministic behavior.", decoder, previousDecoder, data, data.length, priority); } } else { previousDecoder = decoder; previousPriority = priority; } } } return previousDecoder; } // Normal code path for (id decoder in _decoders) { if ([decoder canDecodeImageData:data]) { return decoder; } } return nil; } static UIImage *RCTResizeImageIfNeeded(UIImage *image, CGSize size, CGFloat scale, RCTResizeMode resizeMode) { if (CGSizeEqualToSize(size, CGSizeZero) || CGSizeEqualToSize(image.size, CGSizeZero) || CGSizeEqualToSize(image.size, size)) { return image; } CAKeyframeAnimation *animation = image.reactKeyframeAnimation; CGRect targetSize = RCTTargetRect(image.size, size, scale, resizeMode); CGAffineTransform transform = RCTTransformFromTargetRect(image.size, targetSize); image = RCTTransformImage(image, size, scale, transform); image.reactKeyframeAnimation = animation; return image; } - (RCTImageLoaderCancellationBlock)loadImageWithTag:(NSString *)imageTag callback:(RCTImageLoaderCompletionBlock)callback { return [self loadImageWithTag:imageTag size:CGSizeZero scale:1 resizeMode:RCTResizeModeStretch progressBlock:nil completionBlock:callback]; } - (void)dequeueTasks { dispatch_async(_URLCacheQueue, ^{ // Remove completed tasks for (RCTNetworkTask *task in _pendingTasks.reverseObjectEnumerator) { switch (task.status) { case RCTNetworkTaskFinished: [_pendingTasks removeObject:task]; _activeTasks--; break; case RCTNetworkTaskPending: case RCTNetworkTaskInProgress: // Do nothing break; } } // Start queued decode NSInteger activeDecodes = _scheduledDecodes - _pendingDecodes.count; while (activeDecodes == 0 || (_activeBytes <= _maxConcurrentDecodingBytes && activeDecodes <= _maxConcurrentDecodingTasks)) { dispatch_block_t decodeBlock = _pendingDecodes.firstObject; if (decodeBlock) { [_pendingDecodes removeObjectAtIndex:0]; decodeBlock(); } else { break; } } // Start queued tasks for (RCTNetworkTask *task in _pendingTasks) { if (MAX(_activeTasks, _scheduledDecodes) >= _maxConcurrentLoadingTasks) { break; } if (task.status == RCTNetworkTaskPending) { [task start]; _activeTasks++; } } }); } /** * This returns either an image, or raw image data, depending on the loading * path taken. This is useful if you want to skip decoding, e.g. when preloading * the image, or retrieving metadata. */ - (RCTImageLoaderCancellationBlock)loadImageOrDataWithTag:(NSString *)imageTag size:(CGSize)size scale:(CGFloat)scale resizeMode:(RCTResizeMode)resizeMode progressBlock:(RCTImageLoaderProgressBlock)progressHandler completionBlock:(void (^)(NSError *error, id imageOrData))completionBlock { __block volatile uint32_t cancelled = 0; __block void(^cancelLoad)(void) = nil; __weak RCTImageLoader *weakSelf = self; void (^completionHandler)(NSError *error, id imageOrData) = ^(NSError *error, id imageOrData) { if ([NSThread isMainThread]) { // Most loaders do not return on the main thread, so caller is probably not // expecting it, and may do expensive post-processing in the callback dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{ if (!cancelled) { completionBlock(error, imageOrData); } }); } else if (!cancelled) { completionBlock(error, imageOrData); } }; if (imageTag.length == 0) { completionHandler(RCTErrorWithMessage(@"source.uri should not be an empty string"), nil); return ^{}; } // All access to URL cache must be serialized if (!_URLCacheQueue) { [self setUp]; } dispatch_async(_URLCacheQueue, ^{ if (!_URLCache) { _URLCache = [[NSURLCache alloc] initWithMemoryCapacity:5 * 1024 * 1024 // 5MB diskCapacity:200 * 1024 * 1024 // 200MB diskPath:@"React/RCTImageDownloader"]; } RCTImageLoader *strongSelf = weakSelf; if (cancelled || !strongSelf) { return; } // Find suitable image URL loader NSURLRequest *request = [RCTConvert NSURLRequest:imageTag]; id loadHandler = [strongSelf imageURLLoaderForURL:request.URL]; if (loadHandler) { cancelLoad = [loadHandler loadImageForURL:request.URL size:size scale:scale resizeMode:resizeMode progressHandler:progressHandler completionHandler:completionHandler] ?: ^{}; return; } // Check if networking module is available if (RCT_DEBUG && ![_bridge respondsToSelector:@selector(networking)]) { RCTLogError(@"No suitable image URL loader found for %@. You may need to " " import the RCTNetwork library in order to load images.", imageTag); return; } // Check if networking module can load image if (RCT_DEBUG && ![_bridge.networking canHandleRequest:request]) { RCTLogError(@"No suitable image URL loader found for %@", imageTag); return; } // Use networking module to load image RCTURLRequestCompletionBlock processResponse = ^(NSURLResponse *response, NSData *data, NSError *error) { // Check for system errors if (error) { completionHandler(error, nil); return; } else if (!data) { completionHandler(RCTErrorWithMessage(@"Unknown image download error"), nil); return; } // Check for http errors if ([response isKindOfClass:[NSHTTPURLResponse class]]) { NSInteger statusCode = ((NSHTTPURLResponse *)response).statusCode; if (statusCode != 200) { completionHandler([[NSError alloc] initWithDomain:NSURLErrorDomain code:statusCode userInfo:nil], nil); return; } } // Call handler completionHandler(nil, data); }; // Add missing png extension if (request.URL.fileURL && request.URL.pathExtension.length == 0) { NSMutableURLRequest *mutableRequest = [request mutableCopy]; mutableRequest.URL = [NSURL fileURLWithPath:[request.URL.path stringByAppendingPathExtension:@"png"]]; request = mutableRequest; } // Check for cached response before reloading // TODO: move URL cache out of RCTImageLoader into its own module NSCachedURLResponse *cachedResponse = [_URLCache cachedResponseForRequest:request]; if (cachedResponse) { processResponse(cachedResponse.response, cachedResponse.data, nil); return; } // Download image RCTNetworkTask *task = [_bridge.networking networkTaskWithRequest:request completionBlock:^(NSURLResponse *response, NSData *data, NSError *error) { if (error) { completionHandler(error, nil); return; } dispatch_async(_URLCacheQueue, ^{ // Cache the response // TODO: move URL cache out of RCTImageLoader into its own module BOOL isHTTPRequest = [request.URL.scheme hasPrefix:@"http"]; [strongSelf->_URLCache storeCachedResponse: [[NSCachedURLResponse alloc] initWithResponse:response data:data userInfo:nil storagePolicy:isHTTPRequest ? NSURLCacheStorageAllowed: NSURLCacheStorageAllowedInMemoryOnly] forRequest:request]; // Process image data processResponse(response, data, nil); //clean up [weakSelf dequeueTasks]; }); }]; task.downloadProgressBlock = progressHandler; if (!_pendingTasks) { _pendingTasks = [NSMutableArray new]; } [_pendingTasks addObject:task]; if (MAX(_activeTasks, _scheduledDecodes) < _maxConcurrentLoadingTasks) { [task start]; _activeTasks++; } cancelLoad = ^{ [task cancel]; [weakSelf dequeueTasks]; }; }); return ^{ if (cancelLoad) { cancelLoad(); } OSAtomicOr32Barrier(1, &cancelled); }; } - (RCTImageLoaderCancellationBlock)loadImageWithTag:(NSString *)imageTag size:(CGSize)size scale:(CGFloat)scale resizeMode:(RCTResizeMode)resizeMode progressBlock:(RCTImageLoaderProgressBlock)progressHandler completionBlock:(RCTImageLoaderCompletionBlock)completionBlock { return [self loadImageWithoutClipping:imageTag size:size scale:scale resizeMode:resizeMode progressBlock:progressHandler completionBlock:^(NSError *error, UIImage *image) { completionBlock(error, RCTResizeImageIfNeeded(image, size, scale, resizeMode)); }]; } - (RCTImageLoaderCancellationBlock)loadImageWithoutClipping:(NSString *)imageTag size:(CGSize)size scale:(CGFloat)scale resizeMode:(RCTResizeMode)resizeMode progressBlock:(RCTImageLoaderProgressBlock)progressHandler completionBlock:(RCTImageLoaderCompletionBlock)completionBlock { __block volatile uint32_t cancelled = 0; __block void(^cancelLoad)(void) = nil; __weak RCTImageLoader *weakSelf = self; void (^completionHandler)(NSError *error, id imageOrData) = ^(NSError *error, id imageOrData) { if (!cancelled) { if (!imageOrData || [imageOrData isKindOfClass:[UIImage class]]) { completionBlock(error, imageOrData); } else { cancelLoad = [weakSelf decodeImageDataWithoutClipping:imageOrData size:size scale:scale resizeMode:resizeMode completionBlock:completionBlock] ?: ^{}; } } }; cancelLoad = [self loadImageOrDataWithTag:imageTag size:size scale:scale resizeMode:resizeMode progressBlock:progressHandler completionBlock:completionHandler] ?: ^{}; return ^{ if (cancelLoad) { cancelLoad(); } OSAtomicOr32Barrier(1, &cancelled); }; } - (RCTImageLoaderCancellationBlock)decodeImageData:(NSData *)data size:(CGSize)size scale:(CGFloat)scale resizeMode:(RCTResizeMode)resizeMode completionBlock:(RCTImageLoaderCompletionBlock)completionBlock { return [self decodeImageDataWithoutClipping:data size:size scale:scale resizeMode:resizeMode completionBlock:^(NSError *error, UIImage *image) { completionBlock(error, RCTResizeImageIfNeeded(image, size, scale, resizeMode)); }]; } - (RCTImageLoaderCancellationBlock)decodeImageDataWithoutClipping:(NSData *)data size:(CGSize)size scale:(CGFloat)scale resizeMode:(RCTResizeMode)resizeMode completionBlock:(RCTImageLoaderCompletionBlock)completionBlock { if (data.length == 0) { completionBlock(RCTErrorWithMessage(@"No image data"), nil); return ^{}; } __block volatile uint32_t cancelled = 0; void (^completionHandler)(NSError *, UIImage *) = ^(NSError *error, UIImage *image) { if ([NSThread isMainThread]) { // Most loaders do not return on the main thread, so caller is probably not // expecting it, and may do expensive post-processing in the callback dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{ if (!cancelled) { completionBlock(error, image); } }); } else if (!cancelled) { completionBlock(error, image); } }; id imageDecoder = [self imageDataDecoderForData:data]; if (imageDecoder) { return [imageDecoder decodeImageData:data size:size scale:scale resizeMode:resizeMode completionHandler:completionHandler]; } else { if (!_URLCacheQueue) { [self setUp]; } dispatch_async(_URLCacheQueue, ^{ dispatch_block_t decodeBlock = ^{ // Calculate the size, in bytes, that the decompressed image will require NSInteger decodedImageBytes = (size.width * scale) * (size.height * scale) * 4; // Mark these bytes as in-use _activeBytes += decodedImageBytes; // Do actual decompression on a concurrent background queue dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{ if (!cancelled) { // Decompress the image data (this may be CPU and memory intensive) UIImage *image = RCTDecodeImageWithData(data, size, scale, resizeMode); #if RCT_DEV CGSize imagePixelSize = RCTSizeInPixels(image.size, image.scale); CGSize screenPixelSize = RCTSizeInPixels(RCTScreenSize(), RCTScreenScale()); if (imagePixelSize.width * imagePixelSize.height > screenPixelSize.width * screenPixelSize.height) { RCTLogInfo(@"[PERF ASSETS] Loading image at size %@, which is larger " "than the screen size %@", NSStringFromCGSize(imagePixelSize), NSStringFromCGSize(screenPixelSize)); } #endif if (image) { completionHandler(nil, image); } else { NSString *errorMessage = [NSString stringWithFormat:@"Error decoding image data ", data, data.length]; NSError *finalError = RCTErrorWithMessage(errorMessage); completionHandler(finalError, nil); } } // We're no longer retaining the uncompressed data, so now we'll mark // the decoding as complete so that the loading task queue can resume. dispatch_async(_URLCacheQueue, ^{ _scheduledDecodes--; _activeBytes -= decodedImageBytes; [self dequeueTasks]; }); }); }; // The decode operation retains the compressed image data until it's // complete, so we'll mark it as having started, in order to block // further image loads from happening until we're done with the data. _scheduledDecodes++; if (!_pendingDecodes) { _pendingDecodes = [NSMutableArray new]; } NSInteger activeDecodes = _scheduledDecodes - _pendingDecodes.count - 1; if (activeDecodes == 0 || (_activeBytes <= _maxConcurrentDecodingBytes && activeDecodes <= _maxConcurrentDecodingTasks)) { decodeBlock(); } else { [_pendingDecodes addObject:decodeBlock]; } }); return ^{ OSAtomicOr32Barrier(1, &cancelled); }; } } - (RCTImageLoaderCancellationBlock)getImageSize:(NSString *)imageTag block:(void(^)(NSError *error, CGSize size))completionBlock { return [self loadImageOrDataWithTag:imageTag size:CGSizeZero scale:1 resizeMode:RCTResizeModeStretch progressBlock:nil completionBlock:^(NSError *error, id imageOrData) { CGSize size; if ([imageOrData isKindOfClass:[NSData class]]) { NSDictionary *meta = RCTGetImageMetadata(imageOrData); size = (CGSize){ [meta[(id)kCGImagePropertyPixelWidth] doubleValue], [meta[(id)kCGImagePropertyPixelHeight] doubleValue], }; } else { UIImage *image = imageOrData; size = (CGSize){ image.size.width * image.scale, image.size.height * image.scale, }; } completionBlock(error, size); }]; } #pragma mark - Bridged methods RCT_EXPORT_METHOD(prefetchImage:(NSString *)uri resolve:(RCTPromiseResolveBlock)resolve reject:(RCTPromiseRejectBlock)reject) { if (!uri.length) { reject(RCTErrorInvalidURI, @"Cannot prefetch an image for an empty URI", nil); return; } [_bridge.imageLoader loadImageWithTag:uri callback:^(NSError *error, UIImage *image) { if (error) { reject(RCTErrorPrefetchFailure, nil, error); return; } resolve(@YES); }]; } #pragma mark - RCTURLRequestHandler - (BOOL)canHandleRequest:(NSURLRequest *)request { NSURL *requestURL = request.URL; for (id loader in _loaders) { // Don't use RCTImageURLLoader protocol for modules that already conform to // RCTURLRequestHandler as it's inefficient to decode an image and then // convert it back into data if (![loader conformsToProtocol:@protocol(RCTURLRequestHandler)] && [loader canLoadImageURL:requestURL]) { return YES; } } return NO; } - (id)sendRequest:(NSURLRequest *)request withDelegate:(id)delegate { __block RCTImageLoaderCancellationBlock requestToken; requestToken = [self loadImageWithTag:request.URL.absoluteString callback:^(NSError *error, UIImage *image) { if (error) { [delegate URLRequest:requestToken didCompleteWithError:error]; return; } NSString *mimeType = nil; NSData *imageData = nil; if (RCTImageHasAlpha(image.CGImage)) { mimeType = @"image/png"; imageData = UIImagePNGRepresentation(image); } else { mimeType = @"image/jpeg"; imageData = UIImageJPEGRepresentation(image, 1.0); } NSURLResponse *response = [[NSURLResponse alloc] initWithURL:request.URL MIMEType:mimeType expectedContentLength:imageData.length textEncodingName:nil]; [delegate URLRequest:requestToken didReceiveResponse:response]; [delegate URLRequest:requestToken didReceiveData:imageData]; [delegate URLRequest:requestToken didCompleteWithError:nil]; }]; return requestToken; } - (void)cancelRequest:(id)requestToken { if (requestToken) { ((RCTImageLoaderCancellationBlock)requestToken)(); } } @end @implementation RCTBridge (RCTImageLoader) - (RCTImageLoader *)imageLoader { return [self moduleForClass:[RCTImageLoader class]]; } @end