react-native/Libraries/Image/RCTImageLoader.m

453 lines
15 KiB
Objective-C

/**
* 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 <libkern/OSAtomic.h>
#import <UIKit/UIKit.h>
#import "RCTConvert.h"
#import "RCTDefines.h"
#import "RCTImageUtils.h"
#import "RCTLog.h"
#import "RCTNetworking.h"
#import "RCTUtils.h"
@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<id<RCTImageURLLoader>> *_loaders;
NSArray<id<RCTImageDataDecoder>> *_decoders;
dispatch_queue_t _URLCacheQueue;
NSURLCache *_URLCache;
}
@synthesize bridge = _bridge;
RCT_EXPORT_MODULE()
- (void)setUp
{
// Get image loaders and decoders
NSMutableArray<id<RCTImageURLLoader>> *loaders = [NSMutableArray array];
NSMutableArray<id<RCTImageDataDecoder>> *decoders = [NSMutableArray array];
for (Class moduleClass in _bridge.moduleClasses) {
if ([moduleClass conformsToProtocol:@protocol(RCTImageURLLoader)]) {
[loaders addObject:[_bridge moduleForClass:moduleClass]];
}
if ([moduleClass conformsToProtocol:@protocol(RCTImageDataDecoder)]) {
[decoders addObject:[_bridge moduleForClass:moduleClass]];
}
}
// Sort loaders in reverse priority order (highest priority first)
[loaders sortUsingComparator:^NSComparisonResult(id<RCTImageURLLoader> a, id<RCTImageURLLoader> 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;
}
}];
// Sort decoders in reverse priority order (highest priority first)
[decoders sortUsingComparator:^NSComparisonResult(id<RCTImageDataDecoder> a, id<RCTImageDataDecoder> 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;
}
}];
_loaders = loaders;
_decoders = decoders;
}
- (id<RCTImageURLLoader>)imageURLLoaderForURL:(NSURL *)URL
{
if (!_loaders) {
[self setUp];
}
if (RCT_DEBUG) {
// Check for handler conflicts
float previousPriority = 0;
id<RCTImageURLLoader> previousLoader = nil;
for (id<RCTImageURLLoader> 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<RCTImageURLLoader> loader in _loaders) {
if ([loader canLoadImageURL:URL]) {
return loader;
}
}
return nil;
}
- (id<RCTImageDataDecoder>)imageDataDecoderForData:(NSData *)data
{
if (!_decoders) {
[self setUp];
}
if (RCT_DEBUG) {
// Check for handler conflicts
float previousPriority = 0;
id<RCTImageDataDecoder> previousDecoder = nil;
for (id<RCTImageDataDecoder> 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 <NSData %p; %tu bytes>, 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<RCTImageDataDecoder> decoder in _decoders) {
if ([decoder canDecodeImageData:data]) {
return decoder;
}
}
return nil;
}
- (RCTImageLoaderCancellationBlock)loadImageWithTag:(NSString *)imageTag
callback:(RCTImageLoaderCompletionBlock)callback
{
return [self loadImageWithTag:imageTag
size:CGSizeZero
scale:1
resizeMode:UIViewContentModeScaleToFill
progressBlock:nil
completionBlock:callback];
}
- (RCTImageLoaderCancellationBlock)loadImageWithTag:(NSString *)imageTag
size:(CGSize)size
scale:(CGFloat)scale
resizeMode:(UIViewContentMode)resizeMode
progressBlock:(RCTImageLoaderProgressBlock)progressHandler
completionBlock:(RCTImageLoaderCompletionBlock)completionBlock
{
__block volatile uint32_t cancelled = 0;
__block void(^cancelLoad)(void) = nil;
__weak RCTImageLoader *weakSelf = self;
RCTImageLoaderCompletionBlock completionHandler = ^(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);
}
};
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) {
_URLCacheQueue = dispatch_queue_create("com.facebook.react.ImageLoaderURLCacheQueue", DISPATCH_QUEUE_SERIAL);
}
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<RCTImageURLLoader> 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 RCTNetworking 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
__block RCTImageLoaderCancellationBlock cancelDecode = nil;
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;
}
}
// Decode image
cancelDecode = [strongSelf decodeImageData:data
size:size
scale:scale
resizeMode:resizeMode
completionBlock:completionHandler];
};
// 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);
});
}];
task.downloadProgressBlock = progressHandler;
[task start];
cancelLoad = ^{
[task cancel];
if (cancelDecode) {
cancelDecode();
}
};
});
return ^{
if (cancelLoad) {
cancelLoad();
}
OSAtomicOr32Barrier(1, &cancelled);
};
}
- (RCTImageLoaderCancellationBlock)decodeImageData:(NSData *)data
size:(CGSize)size
scale:(CGFloat)scale
resizeMode:(UIViewContentMode)resizeMode
completionBlock:(RCTImageLoaderCompletionBlock)completionHandler
{
if (data.length == 0) {
completionHandler(RCTErrorWithMessage(@"No image data"), nil);
return ^{};
}
id<RCTImageDataDecoder> imageDecoder = [self imageDataDecoderForData:data];
if (imageDecoder) {
return [imageDecoder decodeImageData:data
size:size
scale:scale
resizeMode:resizeMode
completionHandler:completionHandler];
} else {
__block volatile uint32_t cancelled = 0;
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
if (cancelled) {
return;
}
UIImage *image = RCTDecodeImageWithData(data, size, scale, resizeMode);
if (image) {
completionHandler(nil, image);
} else {
NSString *errorMessage = [NSString stringWithFormat:@"Error decoding image data <NSData %p; %tu bytes>", data, data.length];
NSError *finalError = RCTErrorWithMessage(errorMessage);
completionHandler(finalError, nil);
}
});
return ^{
OSAtomicOr32Barrier(1, &cancelled);
};
}
}
#pragma mark - RCTURLRequestHandler
- (BOOL)canHandleRequest:(NSURLRequest *)request
{
return [self imageURLLoaderForURL:request.URL] != nil;
}
- (id)sendRequest:(NSURLRequest *)request withDelegate:(id<RCTURLRequestDelegate>)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