SDWebImage/SDWebImage/SDWebImageDownloader.h

250 lines
9.1 KiB
Objective-C

/*
* 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 <Foundation/Foundation.h>
#import "SDWebImageCompat.h"
#import "SDWebImageOperation.h"
typedef NS_OPTIONS(NSUInteger, SDWebImageDownloaderOptions) {
SDWebImageDownloaderLowPriority = 1 << 0,
SDWebImageDownloaderProgressiveDownload = 1 << 1,
/**
* By default, request prevent the use of NSURLCache. With this flag, NSURLCache
* is used with default policies.
*/
SDWebImageDownloaderUseNSURLCache = 1 << 2,
/**
* Call completion block with nil image/imageData if the image was read from NSURLCache
* (to be combined with `SDWebImageDownloaderUseNSURLCache`).
*/
SDWebImageDownloaderIgnoreCachedResponse = 1 << 3,
/**
* In iOS 4+, continue the download of the image if the app goes to background. This is achieved by asking the system for
* extra time in background to let the request finish. If the background task expires the operation will be cancelled.
*/
SDWebImageDownloaderContinueInBackground = 1 << 4,
/**
* Handles cookies stored in NSHTTPCookieStore by setting
* NSMutableURLRequest.HTTPShouldHandleCookies = YES;
*/
SDWebImageDownloaderHandleCookies = 1 << 5,
/**
* Enable to allow untrusted SSL certificates.
* Useful for testing purposes. Use with caution in production.
*/
SDWebImageDownloaderAllowInvalidSSLCertificates = 1 << 6,
/**
* Put the image in the high priority queue.
*/
SDWebImageDownloaderHighPriority = 1 << 7,
/**
* Scale down the image
*/
SDWebImageDownloaderScaleDownLargeImages = 1 << 8,
};
typedef NS_ENUM(NSInteger, SDWebImageDownloaderExecutionOrder) {
/**
* Default value. All download operations will execute in queue style (first-in-first-out).
*/
SDWebImageDownloaderFIFOExecutionOrder,
/**
* All download operations will execute in stack style (last-in-first-out).
*/
SDWebImageDownloaderLIFOExecutionOrder
};
FOUNDATION_EXPORT NSString * _Nonnull const SDWebImageDownloadStartNotification;
FOUNDATION_EXPORT NSString * _Nonnull const SDWebImageDownloadStopNotification;
typedef void(^SDWebImageDownloaderProgressBlock)(NSInteger receivedSize, NSInteger expectedSize, NSURL * _Nullable targetURL);
typedef void(^SDWebImageDownloaderCompletedBlock)(UIImage * _Nullable image, NSData * _Nullable data, NSError * _Nullable error, BOOL finished);
typedef NSDictionary<NSString *, NSString *> SDHTTPHeadersDictionary;
typedef NSMutableDictionary<NSString *, NSString *> SDHTTPHeadersMutableDictionary;
typedef SDHTTPHeadersDictionary * _Nullable (^SDWebImageDownloaderHeadersFilterBlock)(NSURL * _Nullable url, SDHTTPHeadersDictionary * _Nullable headers);
/**
* A token associated with each download. Can be used to cancel a download
*/
@interface SDWebImageDownloadToken : NSObject
@property (nonatomic, strong, nullable) NSURL *url;
@property (nonatomic, strong, nullable) id downloadOperationCancelToken;
@end
/**
* Asynchronous downloader dedicated and optimized for image loading.
*/
@interface SDWebImageDownloader : NSObject
/**
* Decompressing images that are downloaded and cached can improve performance but can consume lot of memory.
* Defaults to YES. Set this to NO if you are experiencing a crash due to excessive memory consumption.
*/
@property (assign, nonatomic) BOOL shouldDecompressImages;
/**
* The maximum number of concurrent downloads
*/
@property (assign, nonatomic) NSInteger maxConcurrentDownloads;
/**
* Shows the current amount of downloads that still need to be downloaded
*/
@property (readonly, nonatomic) NSUInteger currentDownloadCount;
/**
* The timeout value (in seconds) for the download operation. Default: 15.0.
*/
@property (assign, nonatomic) NSTimeInterval downloadTimeout;
/**
* The configuration in use by the internal NSURLSession.
* Mutating this object directly has no effect.
*
* @see createNewSessionWithConfiguration:
*/
@property (readonly, nonatomic, nonnull) NSURLSessionConfiguration *sessionConfiguration;
/**
* Changes download operations execution order. Default value is `SDWebImageDownloaderFIFOExecutionOrder`.
*/
@property (assign, nonatomic) SDWebImageDownloaderExecutionOrder executionOrder;
/**
* Singleton method, returns the shared instance
*
* @return global shared instance of downloader class
*/
+ (nonnull instancetype)sharedDownloader;
/**
* Set the default URL credential to be set for request operations.
*/
@property (strong, nonatomic, nullable) NSURLCredential *urlCredential;
/**
* Set username
*/
@property (strong, nonatomic, nullable) NSString *username;
/**
* Set password
*/
@property (strong, nonatomic, nullable) NSString *password;
/**
* Set filter to pick headers for downloading image HTTP request.
*
* This block will be invoked for each downloading image request, returned
* NSDictionary will be used as headers in corresponding HTTP request.
*/
@property (nonatomic, copy, nullable) SDWebImageDownloaderHeadersFilterBlock headersFilter;
/**
* Creates an instance of a downloader with specified session configuration.
* *Note*: `timeoutIntervalForRequest` is going to be overwritten.
* @return new instance of downloader class
*/
- (nonnull instancetype)initWithSessionConfiguration:(nullable NSURLSessionConfiguration *)sessionConfiguration NS_DESIGNATED_INITIALIZER;
/**
* Set a value for a HTTP header to be appended to each download HTTP request.
*
* @param value The value for the header field. Use `nil` value to remove the header.
* @param field The name of the header field to set.
*/
- (void)setValue:(nullable NSString *)value forHTTPHeaderField:(nullable NSString *)field;
/**
* Returns the value of the specified HTTP header field.
*
* @return The value associated with the header field field, or `nil` if there is no corresponding header field.
*/
- (nullable NSString *)valueForHTTPHeaderField:(nullable NSString *)field;
/**
* Sets a subclass of `SDWebImageDownloaderOperation` as the default
* `NSOperation` to be used each time SDWebImage constructs a request
* operation to download an image.
*
* @param operationClass The subclass of `SDWebImageDownloaderOperation` to set
* as default. Passing `nil` will revert to `SDWebImageDownloaderOperation`.
*/
- (void)setOperationClass:(nullable Class)operationClass;
/**
* Creates a SDWebImageDownloader async downloader instance with a given URL
*
* The delegate will be informed when the image is finish downloaded or an error has happen.
*
* @see SDWebImageDownloaderDelegate
*
* @param url The URL to the image to download
* @param options The options to be used for this download
* @param progressBlock A block called repeatedly while the image is downloading
* @note the progress block is executed on a background queue
* @param completedBlock A block called once the download is completed.
* If the download succeeded, the image parameter is set, in case of error,
* error parameter is set with the error. The last parameter is always YES
* if SDWebImageDownloaderProgressiveDownload isn't use. With the
* SDWebImageDownloaderProgressiveDownload option, this block is called
* repeatedly with the partial image object and the finished argument set to NO
* before to be called a last time with the full image and finished argument
* set to YES. In case of error, the finished argument is always YES.
*
* @return A token (SDWebImageDownloadToken) that can be passed to -cancel: to cancel this operation
*/
- (nullable SDWebImageDownloadToken *)downloadImageWithURL:(nullable NSURL *)url
options:(SDWebImageDownloaderOptions)options
progress:(nullable SDWebImageDownloaderProgressBlock)progressBlock
completed:(nullable SDWebImageDownloaderCompletedBlock)completedBlock;
/**
* Cancels a download that was previously queued using -downloadImageWithURL:options:progress:completed:
*
* @param token The token received from -downloadImageWithURL:options:progress:completed: that should be canceled.
*/
- (void)cancel:(nullable SDWebImageDownloadToken *)token;
/**
* Sets the download queue suspension state
*/
- (void)setSuspended:(BOOL)suspended;
/**
* Cancels all download operations in the queue
*/
- (void)cancelAllDownloads;
/**
* Forces SDWebImageDownloader to create and use a new NSURLSession that is
* initialized with the given configuration.
* *Note*: All existing download operations in the queue will be cancelled.
* *Note*: `timeoutIntervalForRequest` is going to be overwritten.
*
* @param sessionConfiguration The configuration to use for the new NSURLSession
*/
- (void)createNewSessionWithConfiguration:(nonnull NSURLSessionConfiguration *)sessionConfiguration;
@end