Open Source Swift Library for Image Editing & Processing

Getting Started with Nuke 

The recommended way to install Nuke is using CocoaPods. Please add the following lines to your Podfile

pod "Nuke"
pod "Nuke-Alamofire-Plugin" # optional
pod "Nuke-AnimatedImage-Plugin" # optional 

Clone the latest sources using the following command.

$ git https://github.com/kean/Nuke.git 

Download & Use Images using Swift

The open source Nuke API provides a well-organized and effective way for downloading and using images inside your Swift apps. To fetch the images you need to pass the URL of the required image and then call the resume method. It will download the requested image in the background and will inform the response closure when it’s done.

// Load images directly using Async/Await
func loadImage() async throws {
    let response = try await pipeline.image(for: url, delegate: self)
}
    
// Use UI components provided by NukeUI mode
struct ContainerView: View {
    var body: some View {
        LazyImage(url: URL(string: "https://example.com/image.jpeg"))
    }
} 

Prefetch Image using Swift API

Prefetching is a very useful feature that enables users to download the image or other data ahead of time in anticipation of its use. The apps can download it and store it in the application’s network cache. Later when you need to view the image the response to your request will come back from the cache instead of the network. The open source API Nuke has included support for an exciting feature known as Prefetching images using Swift code. Please remember that Prefetching can takes up users' data and put extra pressure on the CPU as well as memory. To reduce this pressure you can choose only the disk cache as the prefetching destination.

inal class PrefetchingDemoViewController: UICollectionViewController {
    private let prefetcher = ImagePrefetcher()
    private var photos: [URL] = []

    override func viewDidLoad() {
        super.viewDidLoad()

        collectionView?.isPrefetchingEnabled = true
        collectionView?.prefetchDataSource = self
    }
}

extension PrefetchingDemoViewController: UICollectionViewDataSourcePrefetching {
    func collectionView(_ collectionView: UICollectionView, prefetchItemsAt indexPaths: [IndexPath]) {
        let urls = indexPaths.map { photos[$0.row] }
        prefetcher.startPrefetching(with: urls)
    }

    func collectionView(_ collectionView: UICollectionView, cancelPrefetchingForItemsAt indexPaths: [IndexPath]) {
        let urls = indexPaths.map { photos[$0.row] }
        prefetcher.stopPrefetching(with: urls)
    }
} 

Load and Cash Images via Swift

Image caching is a very useful method that improves application performance and end-user experience. The open source Nuke API enables software apps to automatically cache the downloaded images. Nuke relies on two built-in caching layers. The first one is used to store processed image, which is ready for display. It uses the LRU algorithm – the least recently used entries are removed first during the sweep. The 2^nd one uses HTTP Disk Cache to store the unprocessed image data. It is also possible to check the existence of the requested image in the cache.

let cache = pipeline.cache
let request = ImageRequest(url: URL(string: "https://example.com/image.jpeg")!)

cache.cachedImage(for: request) // From any cache layer
cache.cachedImage(for: request, caches: [.memory]) // Only memory
cache.cachedImage(for: request, caches: [.disk]) // Only disk (decodes data)

let data = cache.cachedData(for: request)
cache.containsData(for: request) // Fast contains check 

// Stores image in the memory cache and stores an encoded
// image in the disk cache
cache.storeCachedImage(ImageContainer(image: image), for: request)

cache.removeCachedImage(for: request)
cache.removeAll()