CHANGELOG.md

Nuke 8

Nuke 8.4.0

November 17, 2019

• Fix an issue with RoundedCorners image processor not respecting the Border parameter – 327, Eric Jensen
• Add an optional border parameter to the Circle processor – 327, Eric Jensen
• Add ImagePipelineObserving and DataLoaderObserving protocols to allow users to tap into the internal events of the subsystems to enable logging and other features – 322
• Deprecate Nuke.Image to avoid name clashes with SwiftUI.Image in the future , add PlatformImage instead – 321
• Make ImagePipeline more readable – 320
• Update demo project to use Swift Package Manager instead of CocoaPods – 319

Nuke 8.3.1

October 26, 2019

• Add dark mode support to the demo project – #307, Li Yu

Nuke 8.3.0

October 06, 2019

• Add processors option to ImagePipeline.Configuration – 300, Alessandro Vendruscolo
• Add queue option to loadImage and loadData methods of ImagePipeline – 304
• Add callbackQueue option to ImagePipeline.Configuration – 304

Nuke 8.2.0

September 20, 2019

• Add support for Mac Catalyst – #299, Jonathan Downing

Nuke 8.1.1

September 1, 2019

• Switch to a versioning scheme which is compatible with Swift Package Manager

Nuke 8.1

August 25, 2019

• Configure dispatch queues with proper QoS – #291, Michael Nisi
• Remove synchronization points in ImageDecoder which is not needed starting from iOS 10 – #277
• Add Swift Package Manager to Installation Guides
• Improve Travis CI setup: run tests on multiple Xcode versions, run thread safety tests, run SwiftLint validations, build demo project, validate Swift package – #279, #280, #281, #284, #285

Nuke 8.0.1

July 21, 2019

• Remove synchronization in ImageDecoder which is no longer needed – #277

Nuke 8.0

July 8, 2019

Nuke 8 is the most powerful, performant, and refined release yet. It contains major advancements it some areas and brings some great new features. One of the highlights of this release is the documentation which was rewritten from the ground up.

Cache processed images on disk · New built-in image processors · ImagePipeline v2 · Up to 30% faster main thread performance · Result type · Improved deduplication · os_signpost integration · Refined ImageRequest API · Smart decompression · Entirely new documentation

Most of the Nuke APIs are source compatible with Nuke 7. There is also a Nuke 8 Migration Guide to help with migration.

Image Processing

#227 Cache Processed Images on Disk

ImagePipeline now supports caching of processed images on disk. To enable this feature set isDataCacheForProcessedDataEnabled to true in the pipeline configuration and provide a dataCache. You can use a built-in DataCache introduced in Nuke 7.3 or write a custom one.

Image cache can significantly improve the user experience in the apps that use heavy image processors like Gaussian Blur.

#243 New Image Processors

Nuke now ships with a bunch of built-in image processors including:

• ImageProcessor.Resize
• ImageProcessor.RoundedCorners
• ImageProcessor.Circle
• ImageProcessor.GaussianBlur
• ImageProcessor.CoreImageFilter

There are also ImageProcessor.Anonymous to create one-off processors from closures and ImageProcessor.Composition to combine two or more processors.

#245 Simplified Processing API

Previously Nuke offered multiple different ways to add processors to the request. Now there is only one, which is also better than all of the previous versions:

let request = ImageRequest(
    url: URL(string: "http://..."),
    processors: [
        ImageProcessor.Resize(size: CGSize(width: 44, height: 44), crop: true),
        ImageProcessor.RoundedCorners(radius: 16)
    ]
)

Processors can also be set using a respective mutable processors property.

Notice that AnyImageProcessor is gone! You can simply use ImageProcessing protocol directly in places where previously you had to use a type-erased version.

#229 Smart Decompression

In the previous versions, decompression was part of the processing API and ImageDecompressor was the default processor set for each image request. This was mostly done to simplify implementation but it was confusing for the users.

In the new version, decompression runs automatically and it no longer a "processor". The new decompression is also smarter. It runs only when needed – when we know that image is still in a compressed format and wasn't decompressed by one of the image processors.

Decompression runs on a new separate imageDecompressingQueue. To disable decompression you can set a new isDecompressionEnabled pipeline configuration option to false.

#247 Avoiding Duplicated Work when Applying Processors

The pipeline avoids doing any duplicated work when loading images. Now it also avoids applying the same processors more than once. For example, let's take these two requests:

let url = URL(string: "http://example.com/image")
pipeline.loadImage(with: ImageRequest(url: url, processors: [
    ImageProcessor.Resize(size: CGSize(width: 44, height: 44)),
    ImageProcessor.GaussianBlur(radius: 8)
]))
pipeline.loadImage(with: ImageRequest(url: url, processors: [
    ImageProcessor.Resize(size: CGSize(width: 44, height: 44))
]))

Nuke will load the image data only once, resize the image once and apply the blur also only once. There is no duplicated work done at any stage. If any of the intermediate results are available in the data cache, they will be used.

ImagePipeline v2

Nuke 8 introduced a major new iteration of the ImagePipeline class. The class was introduced in Nuke 7 and it contained a lot of incidental complexity due to addition of progressive decoding and some other new features. In Nuke 8 it was rewritten to fully embrace progressive decoding. The new pipeline is smaller, simpler, easier to maintain, and more reliable.

It is also faster.

+30% Main Thread Performance

The image pipeline spends even less time on the main thread than any of the previous versions. It's up to 30% faster than Nuke 7.

#239 Load Image Data

Add a new ImagePipeline method to fetch original image data:

@discardableResult
public func loadData(with request: ImageRequest,
                     progress: ((_ completed: Int64, _ total: Int64) -> Void)? = nil,
                     completion: @escaping (Result<(data: Data, response: URLResponse?), ImagePipeline.Error>) -> Void) -> ImageTask

This method now powers ImagePreheater with destination .diskCache introduced in Nuke 7.4 (previously it was powered by a hacky internal API).

#245 Improved ImageRequest API

The rarely used options were extracted into the new ImageRequestOptions struct and the request initializer can now be used to customize all of the request parameters.

#255 filteredURL

You can now provide a filteredURL to be used as a key for caching in case the URL contains transient query parameters:

let request = ImageRequest(
    url: URL(string: "http://example.com/image.jpeg?token=123")!,
    options: ImageRequestOptions(
        filteredURL: "http://example.com/image.jpeg"
    )
)

#241 Adopt Result type

Adopt the Result type introduced in Swift 5. So instead of having a separate response and error parameters, the completion closure now has only one parameter - result.

public typealias Completion = (_ result: Result<ImageResponse, ImagePipeline.Error>) -> Void

Performance

Apart from the general performance improvements Nuke now also offers a great way to measure performance and gain visiblity into how the system behaves when loading images.

#250 Integrate os_signpost

Integrate os_signpost logs for measuring performance. To enable the logs set ImagePipeline.Configuration.isSignpostLoggingEnabled (static property) to true before accessing the shared pipeline.

With these logs, you have visibility into the image pipeline. For more information see WWDC 2018: Measuring Performance Using Logging which explains os_signpost in a great detail.

Documentation

All the documentation for Nuke was rewritten from scratch in Nuke 8. It's now more concise, clear, and it even features some fantastic illustrations:

The screenshots come the the reworked demo project. It gained new demos including Image Processing demo and also a way to change ImagePipeline configuration in runtime.

Misc

• Add a cleaner way to set ImageTask priority using a new priority property – #251
• [macOS] Implement image cost calculation for ImageCache – #236
• [watchOS] Add WKInterfaceImage support
• Future-proof Objective-C ImageDisplaying protocol by adding nuke_ prefixes to avoid clashes in Objective-C runtime
• Add convenience func decode(data: Data) -> Image? method with a default isFinal argument to ImageDecoding protocol – e3ca5e
• Add convenience func process(image: Image) -> Image? method to ImageProcessing protocol
• DataCache will now automatically re-create its root directory if it was deleted underneath it
• Add public flush method to DataCache

Nuke 7

Nuke 7.6.3

May 1, 2019

• Fix #226 ImageTask.setPriority(_:) sometimes crashes

Nuke 7.6.2

Apr 24, 2019

• Fix Thread Sanitizer warnings. The issue was related to unfair_lock usage which was introduced as a replacement for OSAtomic functions in Nuke 7.6. In order to fix the issue, unfair_lock was replaced with simple NSLock. The performance hit is pretty insignificant and definitely isn't worth introducing this additional level of complexity.

Nuke 7.6.1

Apr 13, 2019

• Fix SwiftPM 5.0 support by adding explicit platform version requirements – Vadim Shpakovski in #220
• Update Nuke 7 Migration Guide

Nuke 7.6

Apr 7, 2019

• Add Swift 5.0 support – Daniel Storm in #217
• Add SwiftPM 5.0 support – Vadim Shpakovski in #219
• Remove Swift 4.0 and Swift 4.1 support
• Remove iOS 9, tvOS 9, watchOS 2.0, macOS 10.10 and macOS 10.11 support
• Add a single Nuke target which can build the framework for any platform
• Replace deprecated OSAtomic functions with unfair_lock, there are no performance regressions

Nuke 7.5.2

Dec 26, 2018

• [macOS] Fix Nuke.loadImage image is not displayed when .fadeIn transition is used – #206
• Add .alwaysTransition flag to ImageLoadingOptions – @gabzsa in #201

Nuke 7.5.1

Nov 8, 2018

• Update Swift version in pbxproj to Swift 4.2, #199
• Update demo to Swift 4.2

Nuke 7.5

Oct 21, 2018

Additions

• #193 Add an option to ImageDecompressor to allow images to upscale, thanks to @drkibitz
• #197 Add a convenience initializer to ImageRequest which takes an image processor (ImageProcessing) as a parameter, thanks to @drkibitz

Improvements

• Add a guarantee that if you cancel ImageTask on the main thread, you won't receive any more callbacks (progress, completion)
• Improve internal Operation performance, images are loading up to 5% faster

Removals

Nuke 7 had a lot of API changes, to make the migration easier it shipped with Deprecated.swift file (536 line of code) which enabled Nuke 7 to be almost 100% source-compatible with Nuke 6. It's been 6 months since Nuke 7 release, so now it's finally a good time to remove all of this code.

Nuke 7.4.2

Oct 1, 2018

• #174 Fix an issue with an ImageView reuse logic where in rare cases a wrong image would be displayed, thanks to @michaelnisi

Nuke 7.4.1

Sep 25, 2018

• Disable automatic stopPreheating which was causing some issues

Nuke 7.4

Sep 22, 2018

Prefetching Improvements

• Add an ImagePreheater.Destination option to ImagePreheater. The default option is .memoryCache which works exactly the way ImagePreheater used to work before. The more interesting option is .diskCache. The preheater with .diskCache destination will skip image data decoding entirely to reduce CPU and memory usage. It will still load the image data and store it in disk caches to be used later.
• Add convenience func startPreheating(with urls: [URL]) function which creates requests with .low requests for you.
• ImagePreheater now automatically cancels all of the managed outstanding requests on deinit.
• Add UICollectionViewDataSourcePrefetching demo on iOS 10+. Nuke still supports iOS 9 so Preheat is also still around.

Other Changes

• #187 Fix an issue with progress handler reporting incorrect progress for resumed (206 Partial Content) downloads
• Remove enableExperimentalAggressiveDiskCaching function from ImagePipeline.Configuration, please use DataCache directly instead
• Update Performance Guide

Nuke 7.3.2

Jul 29, 2018

• #178 Fix TSan warning being triggered by performance optimization in ImageTask.cancel() (false positive)
• Fix an issue where a request (ImageRequest) with a default processor and a request with the same processor but set manually would have different cache keys

Nuke 7.3.1

Jul 20, 2018

• ImagePipeline now updates the priority of shared operations when the registered tasks get canceled (was previosuly only reacting to added tasks)
• Fix an issue where didFinishCollectingMetrics closure wasn't called for the tasks completed with images found in memory cache and the tasks canceled before they got a chance to run. Now every created tasks gets a corresponding didFinishCollectingMetrics call.

Nuke 7.3

Jun 29, 2018

This release introduces new DataCache type and features some other improvements in custom data caching.

• Add new DataCache type - a cache backed by a local storage with an LRU cleanup policy. This type is a reworked version of the experimental data cache which was added in Nuke 7.0. It's now much simpler and also faster. It allows for reading and writing in parallel, it has a simple consistent API, and I hope it's going to be a please to use.

Migration note: The storage format - which is simply a bunch of files in a directory really - is backward compatible with the previous implementation. If you'd like the new cache to continue working with the same path, please create it with "com.github.kean.Nuke.DataCache" name and use the same filename generator that you were using before:

try? DataCache(name: "com.github.kean.Nuke.DataCache", filenameGenerator: filenameGenerator)

• #160 DataCache now has a default FilenameGenerator on Swift 4.2 which uses SHA1 hash function provided by CommonCrypto (CommonCrypto is not available on the previous version of Swift).

• #171 Fix a regression introduced in version 7.1. where experimental DataCache would not perform LRU data sweeps.

• Update DataCaching protocol. To store data you now need to implement a synchronous method func cachedData(for key: String) -> Data?. This change was necessary to make the data cache fit nicely in ImagePipeline infrastructure where each stage is managed by a separate OperationQueue and each operation respects the priority of the image requests associated with it.

• Add dataCachingQueue parameter to ImagePipeline.Configuration. The default maxConcurrentOperationCount is 2.

• Improve internal Operation type performance.

Nuke 7.2.1

Jun 18, 2018

Nuke's roadmap is now publicly available. Please feel free to contribute!

This update addresses tech debt introduces in version 7.1 and 7.2. All of the changes made in these version which improved deduplication are prerequisites for implementing smart prefetching which be able to skip decoding, load to data cache only, etc.

Enhancements

• Simpler and more efficient model for managing decoding and processing operations (including progressive ones). All operations now take the request priority into account. The processing operations are now created per processor, not per image loading session which leads to better performance.
• When subscribing to existing session which already started processing, pipeline will try to find existing processing operation.
• Update DFCache integration demo to use new DataCaching protocol
• Added "Default Image Pipeline" section and "Image Pipeline Overview" sections in README.
• Update "Third Party Libraries" guide to use new DataCaching protocol

Nuke 7.2

Jun 12, 2018

Additions

• #163 Add DataCaching protocol which can be used to implement custom data cache. It's not documented yet, the documentation going to be updated in 7.2.1.

Improvements

• Initial iOS 12.0, Swift 4.2 and Xcode 10 beta 1 support
• #167 ImagePipeline now uses OperationQueue instead of DispatchQueue for decoding images. The queue now respects ImageRequest priority. If the task is cancelled the operation added to a queue is also cancelled. The queue can be configured via ImagePipeline.Configuration.
• #167 ImagePipeline now updates processing operations' priority.

Fixes

• Fix a regression where in certain deduplication scenarios a wrong image would be saved in memory cache
• Fix MP4 demo project
• Improve test coverage, bring back DataCache (internal) tests

Nuke 7.1

May 27, 2018

Improvements

• Improve deduplication. Now when creating two requests (at roughly the same time) for the same images but with two different processors, the original image is going to be downloaded once (used to be twice in the previous implementation) and then two separate processors are going to be applied (if the processors are the same, the processing will be performed once).
• Greatly improved test coverage.

Fixes

• Fix an issue when setting custom loadKey for the request, the hashValue of the default key was still used.
• Fix warnings "Decoding failed with error code -1" when progressively decoding images. This was the result of ImageDecoder trying to decode incomplete progressive scans.
• Fix an issue where ImageDecoder could produce a bit more progressive scans than necessary.

Nuke 7.0.1

May 16, 2018

Additions

• Add a section in README about replacing GIFs with video formats (e.g. MP4, WebM)
• Add proof of concept in the demo project that demonstrates loading, caching and displaying short mp4 videos using Nuke

Fixes

• #161 Fix the contentModes not set when initializing an ImageLoadingOptions object

Nuke 7.0

May 10, 2018

Nuke 7 is the biggest release yet. It has a lot of massive new features, new performance improvements, and some API refinements. Check out new Nuke website to see quick videos showcasing some of the new features.

Nuke 7 is almost completely source-compatible with Nuke 6.

Progressive JPEG & WebP

Add support for progressive JPEG (built-in) and WebP (build by the Ryo Kosuge). See README for more info. See demo project to see it in action.

Add new ImageProcessing protocol which now takes an extra ImageProcessingContext parameter. One of its properties is scanNumber which allows you to do things like apply blur to progressive image scans reducing blur radius with each new scan ("progressive blur").

Resumable Downloads (HTTP Range Requests)

If the data task is terminated (either because of a failure or a cancellation) and the image was partially loaded, the next load will resume where it was left off. In many use cases resumable downloads are a massive improvement to user experience, especially on the mobile internet.

Resumable downloads require the server support for HTTP Range Requests. Nuke supports both validators (ETag and Last-Modified).

The resumable downloads are enabled by default. The resumable data is automatically stored in efficient memory cache. This is a good default, but future versions might add more customization options.

Loading Images into Views

Add a new set of powerful methods to load images into views. Here's one of those methods:

@discardableResult
public func loadImage(with request: ImageRequest,
                      options: ImageLoadingOptions = ImageLoadingOptions.shared,
                      into view: ImageDisplayingView,
                      progress: ImageTask.ProgressHandler? = nil,
                      completion: ImageTask.Completion? = nil) -> ImageTask?

You can now pass progress and completion closures as well as new ImageLoadingOptions struct which offers a range of options:

public struct ImageLoadingOptions {
    public static var shared = ImageLoadingOptions()
    public var placeholder: Image?
    public var transition: Transition?
    public var failureImage: Image?
    public var failureImageTransition: Transition?
    public var isPrepareForReuseEnabled = true
    public var pipeline: ImagePipeline?
    public var contentModes: ContentModes?

    /// Content modes to be used for each image type (placeholder, success, failure).
    public struct ContentModes {
        public var success: UIViewContentMode
        public var failure: UIViewContentMode
        public var placeholder: UIViewContentMode
    }

    /// An animated image transition.
    public struct Transition {
        public static func fadeIn(duration: TimeInterval, options: UIViewAnimationOptions = [.allowUserInteraction]) -> Transition
        public static func custom(_ closure: @escaping (ImageDisplayingView, Image) -> Void) -> Transition
    }
}

ImageView will now also automatically prepare itself for reuse (can be disabled via ImageLoadingOptions)

Instead of an ImageTarget protocol we now have a new simple ImageDisplaying protocol which relaxes the requirement what can be used as an image view (it's UIView & ImageDisplaying now). This achieves two things:

• You can now add support for more classes (e.g. MKAnnotationView by implementing ImageDisplaying protocol
• You can override the display(image: method in UIImageView subclasses (e.g. FLAnimatedImageView)

Image Pipeline

The previous Manager + Loading architecture (terrible naming, responsibilities are often confusing) was replaced with a new unified ImagePipeline class. ImagePipeline was built from the ground-up to support all of the powerful new features in Nuke 7 (progressive decoding, resumable downloads, performance metrics, etc).

There is also a new ImageTask class which feels the gap where user or pipeline needed to communicate between each other after the request was started. ImagePipeline and ImageTask offer a bunch of new features:

• To cancel the request you now simply need to call cancel() on the task (ImageTask) which is a bit more user-friendly than previous CancellationTokenSource infrastructure.
• ImageTask offers a new way to track progress (in addition to closures) - native Foundation.Progress (created lazily)
• ImageTask can be used to dynamically change the priority of the executing tasks (e.g. the user opens a new screen, you lower the priority of outstanding tasks)
• In ImagePipeline.Configuration you can now provide custom queues (OperationQueue) for data loading, decoding and processing (separate queue for each stage).
• You can set a custom shared ImagePipeline.

Animated Images (GIFs)

Add built-in support for animated images (everything expect the actual rendering). To enable rendering you're still going to need a third-party library (see FLAnimatedImage and Gifu plugins). The changes made in Nuke dramatically simplified those plugins making both of them essentially obsolete - they both now have 10-30 lines of code, you can just copy this code into your project.

Memory Cache Improvements

• Add new ImageCaching protocol for memory cache which now works with a new ImageRespone class. You can do much more intelligent things in your cache implementations now (e.g. make decisions on when to evict image based on HTTP headers).
• Improve cache write/hit/miss performance by 30% by getting rid of AnyHashable overhead. ImageRequest cacheKey and loadKey are now optional. If you use them, Nuke is going to use them instead of built-in internal ImageRequest.CacheKey and ImageRequest.LoadKey.
• Add TTL support in ImageCache

Aggressive Disk Cache (Experimental)

Add a completely new custom LRU disk cache which can be used for fast and reliable aggressive data caching (ignores HTTP cache control). The new cache lookups are up to 2x faster than URLCache lookups. You can enable it using pipeline's configuration:

When enabling disk cache you must provide a keyEncoder function which takes image request's url as a parameter and produces a key which can be used as a valid filename. The demo project uses sha1 to generate those keys.

$0.enableExperimentalAggressiveDiskCaching(keyEncoder: {
    guard let data = $0.cString(using: .utf8) else { return nil }
    return _nuke_sha1(data, UInt32(data.count))
})

The public API for disk cache and the API for using custom disk caches is going to be available in the future versions.

Existing API already allows you to use custom disk cache by implementing DataLoading protocol, but this is not the most straightforward option.

Performance Metrics

When optimizing performance, it's important to measure. Nuke collects detailed performance metrics during the execution of each image task:

ImagePipeline.shared.didFinishCollectingMetrics = { task, metrics in
    print(metrics)
}

(lldb) po metrics

Task Information {
    Task ID - 1
    Duration - 22:35:16.123 – 22:35:16.475 (0.352s)
    Was Cancelled - false
    Is Memory Cache Hit - false
    Was Subscribed To Existing Session - false
}
Session Information {
    Session ID - 1
    Total Duration - 0.351s
    Was Cancelled - false
}
Timeline {
    22:35:16.124 – 22:35:16.475 (0.351s) - Total
    ------------------------------------
    nil – nil (nil)                      - Check Disk Cache
    22:35:16.131 – 22:35:16.410 (0.278s) - Load Data
    22:35:16.410 – 22:35:16.468 (0.057s) - Decode
    22:35:16.469 – 22:35:16.474 (0.005s) - Process
}
Resumable Data {
    Was Resumed - nil
    Resumable Data Count - nil
    Server Confirmed Resume - nil
}

Other Changes

• ImagePreheater now checks ImageCache synchronously before creating tasks which makes it slightly more efficient.
• RateLimiter now uses the same sync queue as the ImagePipeline reducing a number of dispatched blocks
• Smarter RateLimiter which no longer attempt to execute pending tasks when the bucket isn't full resulting in idle dispatching of blocks. I've used a CountedSet to see how well it works in practice and it's perfect. Nice small win.
• Add ImageDecoderRegistry to configure decoders globally.
• Add ImageDecodingContext to provide as much information as needed to select a decoder.
• ImageTask.Completion now contains ImageResponse (image + URLResponse) instead of just plain image.

Deprecations

• CancellationToken, CancellationTokenSource - continued to be used internally, If you'd like to continue using cancellation tokens please consider copying this code into your project.
• DataDecoding, DataDecoder, DataDecoderComposition - replaced by a new image decoding infrastructure (ImageDecoding, ImageDecoder, ImageDecodingRegistry etc).
• Request renamed to ImageRequest.
• Deprecate Result type. It was only used in a single completion handler so it didn't really justify its existence. More importantly, I wasn't comfortable providing a public Result type as part of the framework.

Nuke 6

Nuke 6.1.1

Apr 9, 2018

• Lower macOS deployment target to 10.10. #156.
• Improve README: add detailed Image Pipeline section, Performance section, rewrite Usage guide

Nuke 6.1

Feb 24, 2018

Features

• Add Request.Priority with 5 available options ranging from .veryLow to .veryHigh. One of the use cases of Request.Priority is to lower the priority of preheating requests. In case requests get deduplicated the task's priority is set to the highest priority of registered requests and gets updated when requests are added or removed from the task.

Improvements

• Fix warnings on Xcode 9.3 beta 3
• Loader implementation changed a bit, it is less clever now and is able to accommodate new features like request priorities
• Minor changes in style guide to make codebase more readable
• Switch to native NSLock, there doesn't seem to be any performance wins anymore when using pthread_mutex directly

Fixes

• #146 fix disk cache path for macOS, thanks to @willdahlberg

Nuke 6.0

Dec 23, 2017

About 8 months ago I finally started using Nuke in production. The project has matured from a playground for experimenting with Swift features to something that I rely on in my day's job.

There are three main areas of improvements in Nuke 6:

• Performance. Nuke 6 is fast! The primary loadImage(with:into:) method is now 1.5x faster thanks to performance improvements of CancellationToken, Manager, Request and Cache types. And it's not just main thread performance, many of the background operations were also optimized.
• API refinements. Some common operations that were surprisingly hard to do are not super easy. And there are no more implementation details leaking into a public API (e.g. classes like Deduplicator).
• Fixes some inconveniences like Thread Sanitizer warnings (false positives!). Improved compile time. Better documentation.

Features

• Implements progress reporting kean#81
• Scaling images is now super easy with new convenience Request initialisers (Request.init(url:targetSize:contentMode: and Request.init(urlRequest:targetSize:contentMode:)
• Add a way to add anonymous image processors to the request (Request.process(key:closure:) and Request.processed(key:closure:))
• Add Loader.Options which can be used to configure Loader (e.g. change maximum number of concurrent requests, disable deduplication or rate limiter, etc).

Improvements

• Improve performance of CancellationTokenSource, Loader, TaskQueue
• Improve Manager performance by reusing contexts objects between requests
• Improve Cache by ~30% for most operations (hits, misses, writes)
• Request now stores all of the parameters in the underlying reference typed container (it used to store just reference typed ones). The Request struct now only has a single property with a reference to an underlying container.
• Parallelize image processing for up to 2x performance boost in certain scenarios. Might increase memory usage. The default maximum number of concurrent tasks is 2 and can be configured using Loader.Options.
• Loader now always call completion on the main thread.
• Move URLResponse validation from DataDecoder to DataLoader
• Make use of some Swift 4 feature like nested types inside generic types.
• Improve compile time.
• Wrap Loader processing and decoding tasks into autoreleasepool which reduced memory footprint.

Fixes

• Get rid of Thread Sanitizer warnings in CancellationTokenSource (false positive)
• Replace Foundation.OperationQueue & custom Foundation.Operation subclass with a new Queue type. It's simpler, faster, and gets rid of pesky Thread Sanitizer warnings kean#141

Removed APIs

• Remove global loadImage(...) functions kean#142
• Remove static Request.loadKey(for:) and Request.cacheKey(for:) functions. The keys are now simply returned in Request's loadKey and cacheKey properties which are also no longer optional now.
• Remove Deduplicator class, make this functionality part of Loader. This has a number of benefits: reduced API surface, improves performance by reducing the number of queue switching, enables new features like progress reporting.
• Remove Scheduler, AsyncScheduler, Loader.Schedulers, DispatchQueueScheduler, OperationQueueScheduler. This whole infrastructure was way too excessive.
• Make RateLimiter private.
• DataLoader now works with URLRequest, not Request

Nuke 5

Nuke 5.2

Sep 1, 2017

Add support for both Swift 3.2 and 4.0.

Nuke 5.1.1

Jun 11, 2017

• Fix Swift 4 warnings
• Add DataDecoder.sharedUrlCache to easy access for shared URLCache object
• Add references to RxNuke
• Minor improvements under the hood

Nuke 5.1

Feb 23, 2017

• De facto Manager has already implemented Loading protocol in Nuke 5 (you could use it to load images directly w/o targets). Now it also conforms to Loading protocols which gives access to some convenience functions available in Loading extensions.
• Add static func targetSize(for view: UIView) -> CGSize method to Decompressor
• Simpler, faster Preheater
• Improved documentation

Nuke 5.0.1

Feb 2, 2017

• #116 Manager can now be used to load images w/o specifying a target
• Preheater is now initialized with Manager instead of object conforming to Loading protocol

Nuke 5.0

• Feb 1, 2017*

Overview

Nuke 5 is a relatively small release which removes some of the complexity from the framework.

One of the major changes is the removal of promisified API as well as Promise itself. Promises were briefly added in Nuke 4 as an effort to simplify async code. The major downsides of promises are compelex memory management, extra complexity for users unfamiliar with promises, complicated debugging, performance penalties. Ultimately I decided that promises were adding more problems that they were solving.

Changes

Removed promisified API and Promise itself

• Remove promisified API, use simple closures instead. For example, Loading protocol's method func loadImage(with request: Request, token: CancellationToken?) -> Promise<Image> was replaced with a method with a completion closure func loadImage(with request: Request, token: CancellationToken?, completion: @escaping (Result<Image>) -> Void). The same applies to DataLoading protocol.
• Remove Promise class
• Remove PromiseResolution<T> enum
• Remove Response typealias
• Add Result<T> enum which is now used as a replacement for PromiseResolution<T> (for instance, in Target protocol, etc)

Memory cache is now managed exclusively by Manager

• Remove memory cache from Loader
• Manager now not only reads, but also writes to Cache
• Manager now has new methods to load images w/o target (Nuke 5.0.1)

The reason behind this change is to reduce confusion about Cache usage. In previous versions the user had to pass Cache instance to both Loader (which was both reading and writing to cache asynchronously), and to Manager (which was just reading from the cache synchronously). In a new setup it's clear who's responsible for managing memory cache.

Removed DataCaching and CachingDataLoader

Those two types were included in Nuke to make integrating third party caching libraries a bit easier. However, they were actually not that useful. Instead of using those types you could've just wrapped DataLoader yourself with a comparable amount of code and get much more control. For more info see Third Party Libraries: Using Other Caching Libraries.

Other Changes

• Loader constructor now provides a default value for DataDecoding object
• DataLoading protocol now works with a Nuke.Request and not URLRequest in case some extra info from URLRequest is required
• Reduce default URLCache disk capacity from 200 MB to 150 MB
• Reduce default maxConcurrentOperationCount of DataLoader from 8 to 6
• Shared objects (like Manager.shared) are now constants.
• Preheater is now initialized with Manager instead of Loading object
• Add new Third Party Libraries guide.
• Improved documentation

Nuke 4

Nuke 4.1.2

Oct 22, 2016

Bunch of improvements in built-in Promise:

• Promise now also uses new Lock - faster creation, faster locking
• Add convenience isPending, resolution, value and error properties
• Simpler implementation migrated from Pill.Promise*

*Nuke.Promise is a simplified variant of Pill.Promise (doesn't allow throws, adds completion, etc). The Promise is built into Nuke to avoid fetching external dependencies.

Nuke 4.1.1

Oct 4, 2016

• Fix deadlock in Cache - small typo, much embarrassment 😄 (kean/Nuke-Alamofire-Plugin#8)

Nuke 4.1 ⚡️

Oct 4, 2016

Nuke 4.1 is all about performance. Here are some notable performance improvements:

• loadImage(with:into:) method with a default config is 6.3x faster
• Cache operations (write/hit/miss) are from 3.1x to 4.5x faster

Nuke 4.0 focused on stability first, naturally there were some performance regressions. With the version 4.1 Nuke is again the fastest framework out there. The performance is ensured by a new set of performance tests.

If you're interested in the types of optimizations that were made check out recent commits. There is a lot of awesome stuff there!

Nuke 4.1 also includes a new Performance Guide and a collection of Tips and Tricks.

Other Changes

• Add convenience method loadImage(with url: URL, into target: AnyObject, handler: @escaping Handler) (more useful than anticipated).
• #88 Add convenience cancelRequest(for:) function
• Use @discardableResult in Promise where it makes sense
• Simplified Loader implementation
• Cache nodes are no longer deallocated recursively on removeAll() and deinit (I was hitting stack limit in benchmarks, it's impossible in real-world use).
• Fix: All Cache public trim() methods are now thread-safe too.

Nuke 4.0 🚀

Sep 19, 2016

Overview

Nuke 4 has fully adopted the new Swift 3 changes and conventions, including the new API Design Guidelines.

Nuke 3 was already a slim framework. Nuke 4 takes it a step further by simplifying almost all of its components.

Here's a few design principles adopted in Nuke 4:

• Protocol-Oriented Programming. Nuke 3 promised a lot of customization by providing a set of protocols for loading, caching, transforming images, etc. However, those protocols were vaguely defined and hard to implement in practice. Protocols in Nuke 4 are simple and precise, often consisting of a single method.
• Single Responsibility Principle. For example, instead of implementing preheating and deduplicating of equivalent requests in a single vague ImageManager class, those features were moved to separate classes (Preheater, Deduplicator). This makes core classes much easier to reason about.
• Principle of Least Astonishment. Nuke 3 had a several excessive protocols, classes and methods which are all gone now (ImageTask, ImageManagerConfiguration just to name a few). Those features are much easier to use now.
• Simpler Async. Image loading involves a lot of asynchronous code, managing it was a chore. Nuke 4 adopts two design patterns (Promise and CancellationToken) that solve most of those problems.

The adoption of those design principles resulted in a simpler, more testable, and more concise code base (which is now under 900 slocs, compared to AlamofireImage's 1426, and Kingfisher's whopping 2357).

I hope that Nuke 4 is going to be a pleasure to use. Thanks for your interest 😄

You can learn more about Nuke 4 in an in-depth Nuke 4 Migration Guide.

Highlighted New Features

LRU Memory Cache

Nuke 4 features a new custom LRU memory cache which replaced NSCache. The primary reason behind this change was the fact that NSCache is not LRU. The new Nuke.Cache has some other benefits like better performance, and more control which would enable some new advanced features in future versions.

Rate Limiter

There is a known problem with URLSession that it gets trashed pretty easily when you resume and cancel URLSessionTasks at a very high rate (say, scrolling a large collection view with images). Some frameworks combat this problem by simply never cancelling URLSessionTasks which are already in .running state. This is not an ideal solution, because it forces users to wait for cancelled requests for images which might never appear on the display.

Nuke has a better, classic solution for this problem - it introduces a new RateLimiter class which limits the rate at which URLSessionTasks are created. RateLimiter uses a token bucket algorithm. The implementation supports quick bursts of requests which can be executed without any delays when "the bucket is full". This is important to prevent the rate limiter from affecting "normal" requests flow. RateLimiter is enabled by default.

You can see RateLimiter in action in a new Rate Limiter Demo added in the sample project.

Toucan Plugin

Make sure to check out new Toucan plugin which provides a simple API for processing images. It supports resizing, cropping, rounded rect masking and more.

Nuke 3

Nuke 3.2

Sep 8, 2016

• Swift 2.3 support
• Preheating is now thread-safe #75

Nuke 3.1.3

Jul 17, 2016

#72 Fix synchronization issue in ImageManager loader:task:didFinishWithImage... method

Nuke 3.1.2

Jul 14, 2016

• #71 ImageViewLoadingController now cancels tasks synchronously, thanks to @adomanico

Nuke 3.1.1

Jun 7, 2016

• Demo project update to support CocoaPods 1.0
• #69 Bitcode support for Carthage builds, thanks to @vincentsaluzzo

Nuke 3.1

Apr 15, 2016

• #64 Fix a performance regression: images are now decoded once per DataTask like they used to
• #65 Fix an issue custom on-disk cache (ImageDiskCaching) was called setData(_:response:forTask:) method when the error wasn't nil
• Add notifications for NSURLSessionTask state changes to enable activity indicators (based on kean/Nuke-Alamofire-Plugin#4)

Nuke 3.0

Mar 26, 2016

• Update for Swift 2.2
• Move ImagePreheatController to a standalone package Preheat
• Remove deprecated suspend method from ImageTask
• Remove ImageFilterGaussianBlur and Core Image helper functions which are now part of Core Image Integration Guide
• Cleanup project structure (as expected by SPM)
• Manager constructor now has a default value for configuration
• nk_setImageWith(URL:) method no longer resizes images by default, because resizing is not effective in most cases
• Remove nk_setImageWith(request:options:placeholder:) method, it's trivial
• ImageLoadingView default implementation no longer implements "Cross Dissolve" animations, use ImageViewLoadingOptions instead (see animations or handler property)
• Remove ImageViewDefaultAnimationDuration, use ImageViewLoadingOptions instead (see animations property)
• ImageDisplayingView protocol now has a single nk_displayImage(_) method instead of a nk_image property
• Remove nk_targetSize property from UI(NS)View extension

Nuke 2

Nuke 2.3

Mar 19, 2016

• #60 Add custom on-disk caching support (see ImageDiskCaching protocol)
• Reduce dynamic dispatch

Nuke 2.2

Mar 11, 2016

• ImageTask suspend method is deprecated, implementation does nothing
• ImageLoader now limits a number of concurrent NSURLSessionTasks
• Add maxConcurrentSessionTaskCount property to ImageLoaderConfiguration
• Add taskReusingEnabled property to ImageLoaderConfiguration
• Add Swift Package Manager support
• Update documentation

Nuke 2.1

Feb 27, 2016

• #57 ImageDecompressor now uses CGImageAlphaInfo.NoneSkipLast for opaque images
• Add ImageProcessorWithClosure that can be used for creating anonymous image filters
• ImageLoader ensures thread safety of image initializers by running decoders on a NSOperationQueue with maxConcurrentOperationCount=1. However, ImageDecoder class is now also made thread safe.

Nuke 2.0.1

Feb 10, 2016

• #53 ImageRequest no longer uses NSURLSessionTaskPriorityDefault, which requires CFNetwork that doesn't get added as a dependency automatically

Nuke 2.0

Feb 6, 2016

Nuke now has an official website!

Main Changes

• #48 Update according to Swift API Design Guidelines. All APIs now just feel right.
• Add UIImage extension with helper functions for Core Image: nk_filter(_:), etc.
• Add ImageFilterGaussianBlur as an example of a filter on top of Core Image framework
• Add ImageRequestMemoryCachePolicy enum that specifies the way Manager interacts with a memory cache; NSURLRequestCachePolicy no longer affects memory cache
• #17 Add priority to ImageRequest
• Add removeResponseForKey() method to ImageMemoryCaching protocol and the corresponding method to Manager
• Implement congestion control for ImageLoader that prevents NSURLSession trashing
• Simplify ImageLoaderDelegate by combining methods that were customizing processing in a single high-level method: imageLoader(_:processorFor:image:). Users now have more control over processing
• Add NSURLResponse? parameter to decode method from ImageDecoding protocol
• DataLoading protocol no longer has isLoadEquivalentRequest(_:toRequest) and isCacheEquivalentRequest(_:toRequest). Those methods are now part of ImageLoaderDelegate and they have default implementation
• ImageResponseInfo is now a struct
• Improved error reporting (codes are now stored in enum, more codes were added, error is now created with a failure reason)

UI Extensions Changes

• Move nk_ImageTask(_:didFinishWithResponse:options) method to ImageLoadingView protocol, that's really where it belongs to
• Add handler property to ImageViewLoadingOptions that allows you to completely override display/animate logic in ImageLoadingView
• Remove nk_prepareForReuse method from ImageLoadingView extensions (useless)
• Remove placeholder from ImageViewLoadingOptions, move it to a separate argument which is only available on ImageDisplayingViews
• Add animated, userInfo to ImageViewLoadingOptions
• ImageViewLoadingOptions is now nonull everywhere
• Add setImageWith(task:options:) method to ImageViewLoadingController

Other Changes

• If you add a completion handler for completed task, the response is now marked as isFastResponse = true
• Fix an issue that allowed incomplete image downloads to finish successfully when using built-in networking
• equivalentProcessors(rhs:lhs:) function is now private (and it also is renamed)
• Remove public isLoadEquivalentToRequest(_:) and isCacheEquivalentToRequest(_:) methods from ImageRequest extension
• Add ImageTaskProgress struct that represents load progress, move fractionCompleted property from ImageTask to ImageTaskProgress
• Remove public helper function allowsCaching from ImageRequest extension
• Remove deprecated XCPSetExecutionShouldContinueIndefinitely from playground

Nuke 1

Nuke 1.4

Jan 9, 2016

• #46 Add option to disable memory cache storage, thanks to @RuiAAPeres

Nuke 1.3

Dec 7, 2015

• Add Core Image Integration Guide
• Fill most of the blanks in the documentation
• #47 Fix target size rounding errors in image downscaling (Pyry Jahkola @pyrtsa)
• Add imageScale property to ImageDecoder class that returns scale to be used when creating UIImage (iOS, tvOS, watchOS only)
• Wrap each iteration in ProcessorComposition in an autoreleasepool

Nuke 1.2

Nov 15, 2015

• #20 Add preheating for UITableView (see ImagePreheatControllerForTableView class)
• #41 Enhanced tvOS support thanks to @joergbirkhold
• #39 UIImageView: ImageLoadingView extension no available on tvOS
• Add factory method for creating session tasks in DataLoader
• Improved documentation

Nuke 1.1.1

Oct 30, 2015

• #35 ImageDecompressor now uses 32 bpp, 8 bpc, CGImageAlphaInfo.PremultipliedLast pixel format which adds support for images in an obscure formats, including 16 bpc images.
• Improve docs

Nuke 1.1

Oct 23, 2015

• #25 Add tvOS support
• #33 Add app extensions support for OSX target (other targets were already supported)

Nuke 1.0

Oct 18, 2015

• #30 Add new protocols and extensions to make it easy to add full featured image loading capabilities to custom UI components. Here's how it works:

extension MKAnnotationView: ImageDisplayingView, ImageLoadingView {
    // That's it, you get default implementation of all the methods in ImageLoadingView protocol
    public var nk_image: UIImage? {
        get { return self.image }
        set { self.image = newValue }
    }
}

• #30 Add UIImageView extension instead of custom UIImageView subclass
• Back to the Mac! All new protocol and extensions for UI components (#30) are also available on a Mac, including new NSImageView extension.
• #26 Add getImageTaskWithCompletion(_:) method to Manager
• Add essential documentation
• Add handy extensions to ImageResponse

Nuke 0.x

Nuke 0.5.1

Oct 13, 2015

Nuke is now available almost everywhere. Also got rid of CocoaPods subspecs.

New Supported Platforms

• CocoaPods, Nuke, watchOS
• CocoaPods, Nuke, OSX
• CocoaPods, NukeAlamofirePlugin, watchOS
• CocoaPods, NukeAlamofirePlugin, OSX
• Carthage, Nuke, watchOS
• Carthage, Nuke, OSX
• Carthage, NukeAlamofirePlugin, iOS
• Carthage, NukeAlamofirePlugin, watchOS
• Carthage, NukeAlamofirePlugin, OSX

Repo Changes

• Remove Nuke/Alamofire subspec, move sources to separate repo Nuke-Alamofire-Plugin
• Remove Nuke/GIF subspec, move sources to separate repo Nuke-AnimatedImage-Plugin

Code Changes

• #9, #19 ImageTask now has a closure for progress instead of NSProgress
• Rename ImageLoadingDelegate to ImageLoadingManager
• Add ImageLoaderDelegate with factory method to construct image decompressor, and shouldProcessImage(_:) method
• Make ImageRequest extensions public
• Make ImageTask constructor public; Annotate abstract methods.

Nuke 0.5

Oct 9, 2015

This is a pre-1.0 version, first major release which is going to be available soon.

Major

• #18 ImageTask can now be suspended (see suspend() method). Add suspendLoadingForImageTask(_:) method to ImageLoading protocol
• #24 ImageRequest can now be initialized with NSURLRequest. ImageDataLoading imageDataTaskWithURL(_:progressHandler:completionHandler:) method changed to imageDataTaskWithRequest(_:progressHandler:completionHandler:). First parameter is ImageRequest, return value change from NSURLSessionDataTask to NSURLSessionTask.
• ImageLoader no longer limits number of concurrent NSURLSessionTasks (which had several drawbacks)
• Add base ImagePreheatingController class
• Multiple preheating improvements: significantly simplified implementation; visible index paths are now subtracted from preheat window; performance improvements.

Minor

• BUGFIX: When subscribing to an existing NSURLSessionTask user was receiving progress callback with invalid totalUnitCount
• Add public equivalentProcessors(lhs:rhs:) -> Bool function that works on optional processors
• Add essential documentation

Nuke 0.4

Oct 4, 2015

Major

• Make ImageLoading protocol and ImageLoader class public
• Make ImageManager cachedResponseForRequest(_:) and storeResponse(_:forRequest:) methods public
• Make ImageRequestKey class and ImageRequestKeyOwner protocol public
• Remove unused ImageManaging and ImagePreheating protocols

Minor

• #13 BUGFIX: Crash on 32-bit iOS simulator on Mac with 16Gb+ of RAM (@RuiAAPeres)
• BUGFIX: Processing operation might not get cancelled in certain situations
• ImageProcessing protocol now provides default implementation for isEquivalentToProcessor(_:) method including separate implementation for processors that also conform to Equatable protocol.
• Add identifier: Int property to ImageTask
• ImageRequestKey now relies on Hashable and Equatable implementation provided by NSObject
• ImageMemoryCaching protocol now works with ImageRequestKey class

Plumbing

• Adopt multiple Swift best practices (tons of them in fact)
• ImageManager is now fully responsible for memory caching and preheating, doesn't delegate any work to ImageLoader (simplifies its implementation and limits dependencies)
• Remove ImageRequestKeyType enum
• Rename ImageManagerLoader to ImageLoader
• Simply ImageManagerLoader (now ImageLoader) implementation
• Add multiple unit tests

Nuke 0.3.1

Sep 22, 2015

#10 Fix Carthage build

Nuke 0.3

Sep 21, 2015

• ImageTask now acts like a promise
• ImageManager.shared is now a property instead of a method
• ImageTask progress is now created lazily
• Add maxConcurrentTaskCount to ImageManagerConfiguration
• Move taskWithURL method to ImageManaging extension
• Add ImagePreheating protocol
• Multiple improvements across the board

Nuke 0.2.2

Sep 20, 2015

• Add limited Carthage support (doesn't feature FLAnimatedImage and Alamofire integration yet, you'll have to stick with CocoaPods for that)
• ImageTask resume() and cancel() methods now return Self
• ImageTask completion property is now public
• Minor implementation improvements

Nuke 0.2.1

Sep 19, 2015

• Add ImageCollectionViewPreheatingController (yep)
• Add Image Preheating Guide
• Add preheating demo

Nuke 0.2

Sep 18, 2015

Major

• Optional Alamofire integration via 'Nuke/Alamofire' subspec
• Optional FLAnimatedImage integration via 'Nuke/GIF' subspec
• More concise API
• Add image filters to ImageRequest
• Add ImageManaging protocol
• Add ImageDecoderComposition
• Add ImageProcessorComposition
• watchOS
• Add convenience functions that forward calls to the shared manager

Minor

• Use ErrorType
• Add removeAllCachedImages method
• ImageRequest userInfo is now Any? so that you can pass anything including closures
• ImageResponseInfo now has userInfo: Any? property
• ImageResponseInfo is now a struct
• CachedImageResponse renamed to ImageCachedResponse; userInfo is now Any?
• Multiple improvements across the board

Nuke 0

Mar 11, 2015

• Initial commit