AlamofireImage Disk Cache not working
alamofire, alamofireimage, ios, swift
Solution
To reach your goal make your `NSURLCache` which you use as diskCache really custom to set your own expiration date for the stored images:
class DiskCache: NSURLCache {
private let constSecondsToKeepOnDisk = 30*24*60*60 // 30 days
override func storeCachedResponse(cachedResponse: NSCachedURLResponse, forRequest request: NSURLRequest) {
var customCachedResponse = cachedResponse
// Set custom Cache-Control for Image-Response
if let response = cachedResponse.response as? NSHTTPURLResponse,
let contentType = response.allHeaderFields["Content-Type"] as? String,
var newHeaders = response.allHeaderFields as? [String: String] where contentType.containsString("image") {
newHeaders["Cache-Control"] = "public, max-age=\(constSecondsToKeepOnDisk)"
if let url = response.URL, newResponse = NSHTTPURLResponse(URL: url, statusCode: response.statusCode, HTTPVersion: "HTTP/1.1", headerFields: newHeaders) {
customCachedResponse = NSCachedURLResponse(response: newResponse, data: cachedResponse.data, userInfo: cachedResponse.userInfo, storagePolicy: cachedResponse.storagePolicy)
}
}
super.storeCachedResponse(customCachedResponse, forRequest: request)
}
}
Instead of creating a new `ImageDownloader` every time you could reuse the shared instance to call the `downloadImage` method: `UIImageView.af_sharedImageDownloader.downloadImage(URLRequest: request)`
Problem
I want to use AlamofireImage to download images from an url and then cache it on the device disk space. I read several posts about this and found out that AlamofireImage supports this with the help of the ImageDownloader class. The most interesting information was given in this SO answer So I tried to set a custom NSURLCache for the ImageDownloader so that it would cache the images directly to the disk. I did that by setting the memory capacity to 0. Then I use this custom ImageDownloader to download an image. The folder that I specified for the disk path is created on the disk but unfortunately it stays empty and the image is not cached in any way. ** Edit:** It is important to notice that the cached responses are not saved in the folder in the caches directory but in a database file next to the folder. Can anybody tell me what I am doing wrong here? Thanks very much for reading! ``` func diskImageDownloader(diskSpaceMB: Int = 100) -> ImageDownloader { let diskCapacity = diskSpaceMB * 1024 * 1024 let diskCache = NSURLCache(memoryCapacity: 0, diskCapacity: diskCapacity, diskPath: "alamofireimage_disk_cache") let configuration = NSURLSessionConfiguration.defaultSessionConfiguration() configuration.URLCache = diskCache let downloader = ImageDownloader(configuration: configuration) UIImageView.af_sharedImageDownloader = downloader return downloader } func getProfileImage(atURL url: String, onComplete: SRServiceResponse<UIImage> -> Void) { guard let imageURL = NSURL(string: url) else { // TODO: Fail here return } let request = NSURLRequest(URL: imageURL) let imageDownloader = self.diskImageDownloader() imageDownloader.downloadImage(URLRequest: request) { (response) in switch response.result { case .Success(let image): // Do something case .Failure(let error): // Do something } } } ```