Fix high memory usage in Reader

Podfile

@@ -42,7 +42,7 @@ def aztec
 end
 
 def wordpress_ui
-  pod 'WordPressUI', '~> 1.12.5'
+  pod 'WordPressUI', '~> 1.14'
   # pod 'WordPressUI', git: 'https://github.com/wordpress-mobile/WordPressUI-iOS', tag: ''
   # pod 'WordPressUI', git: 'https://github.com/wordpress-mobile/WordPressUI-iOS', branch: ''
   # pod 'WordPressUI', git: 'https://github.com/wordpress-mobile/WordPressUI-iOS', commit: ''

Podfile.lock

@@ -519,7 +519,7 @@ PODS:
     - WordPressShared (~> 2.0-beta)
     - wpxmlrpc (~> 0.10)
   - WordPressShared (2.2.0)
-  - WordPressUI (1.12.5)
+  - WordPressUI (1.14.0)
   - WPMediaPicker (1.8.8)
   - wpxmlrpc (0.10.0)
   - Yoga (1.14.0)
@@ -614,7 +614,7 @@ DEPENDENCIES:
   - WordPressAuthenticator (~> 6.3-beta)
   - WordPressKit (~> 8.5)
   - WordPressShared (~> 2.2)
-  - WordPressUI (~> 1.12.5)
+  - WordPressUI (~> 1.14)
   - WPMediaPicker (~> 1.8.8)
   - Yoga (from `https://raw.githubusercontent.com/wordpress-mobile/gutenberg-mobile/v1.100.1/third-party-podspecs/Yoga.podspec.json`)
   - ZendeskSupportSDK (= 5.3.0)
@@ -882,7 +882,7 @@ SPEC CHECKSUMS:
   WordPressAuthenticator: 9bfb316cb165e1997b73aa94d92fadc991cc9725
   WordPressKit: f6943a6e927e9f57bc8793938af1e3a4c3adb614
   WordPressShared: 87f3ee89b0a3e83106106f13a8b71605fb8eb6d2
-  WordPressUI: c5be816f6c7b3392224ac21de9e521e89fa108ac
+  WordPressUI: 09b5477f8678446f27e651cccb6b6401bd19d9a3
   WPMediaPicker: 0d40b8d66b6dfdaa2d6a41e3be51249ff5898775
   wpxmlrpc: 68db063041e85d186db21f674adf08d9c70627fd
   Yoga: 5e12f4deb20582f86f6323e1cdff25f07afc87f6
@@ -895,6 +895,6 @@ SPEC CHECKSUMS:
   ZendeskSupportSDK: 3a8e508ab1d9dd22dc038df6c694466414e037ba
   ZIPFoundation: ae5b4b813d216d3bf0a148773267fff14bd51d37
 
-PODFILE CHECKSUM: bc29b8c7c29da0feaa4a5ed3dff2a805e1a06a93
+PODFILE CHECKSUM: e815177754512909cfd69c325e5898954f2e6525
 
 COCOAPODS: 1.12.1

WordPress/Classes/System/WordPressAppDelegate.swift

@@ -91,6 +91,7 @@ class WordPressAppDelegate: UIResponder, UIApplicationDelegate {
     func application(_ application: UIApplication, willFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? = nil) -> Bool {
         window = UIWindow(frame: UIScreen.main.bounds)
         AppAppearance.overrideAppearance()
+        MemoryCache.shared.register()
 
         // Start CrashLogging as soon as possible (in case a crash happens during startup)
         try? loggingStack.start()

WordPress/Classes/Utility/UIAlertControllerProxy.m

@@ -1,5 +1,4 @@
 #import "UIAlertControllerProxy.h"
-#import <WordPressUI/WordPressUI.h>
 #import "WordPress-Swift.h"
 
 

WordPress/Classes/Utility/WPError.m

@@ -1,7 +1,6 @@
 #import "WPError.h"
 #import "WPAccount.h"
 #import <WordPressShared/NSString+XMLExtensions.h>
-#import <WordPressUI/WordPressUI.h>
 #import <wpxmlrpc/WPXMLRPC.h>
 #import "WordPress-Swift.h"
 

WordPress/Classes/Utility/WPWebViewController.m

@@ -5,7 +5,6 @@
 #import "Constants.h"
 #import "WPError.h"
 #import "WPStyleGuide+WebView.h"
-#import <WordPressUI/WordPressUI.h>
 #import <WordPressShared/UIDevice+Helpers.h>
 #import "WordPress-Swift.h"
 

WordPress/Classes/ViewRelated/Blog/SharingAuthorizationHelper.m

@@ -4,8 +4,6 @@
 #import "BlogService.h"
 #import "SVProgressHUD+Dismiss.h"
 
-#import <WordPressUI/WordPressUI.h>
-
 #import "WordPress-Swift.h"
 
 

WordPress/Classes/ViewRelated/Blog/SharingConnectionsViewController.m

@@ -5,7 +5,6 @@
 #import "SharingDetailViewController.h"
 #import "SharingAuthorizationHelper.h"
 #import <WordPressShared/WPTableViewCell.h>
-#import <WordPressUI/WordPressUI.h>
 #import "WordPress-Swift.h"
 
 

WordPress/Classes/ViewRelated/Blog/SharingDetailViewController.m

@@ -4,7 +4,6 @@
 #import "SVProgressHUD+Dismiss.h"
 #import "SharingAuthorizationHelper.h"
 #import <WordPressShared/WPTableViewCell.h>
-#import <WordPressUI/WordPressUI.h>
 #import "WordPress-Swift.h"
 
 

WordPress/Classes/ViewRelated/Comments/EditCommentViewController.m

@@ -2,7 +2,6 @@
 #import "CommentService.h"
 #import "CoreDataStack.h"
 
-#import <WordPressUI/WordPressUI.h>
 #import "WordPress-Swift.h"
 
 

WordPress/Classes/ViewRelated/Me/Views/Header/MeHeaderView.m

@@ -1,6 +1,5 @@
 #import "MeHeaderView.h"
 #import "Blog.h"
-#import <WordPressUI/WordPressUI.h>
 #import "WordPress-Swift.h"
 
 

WordPress/Classes/ViewRelated/Media/AnimatedImageCache.swift

@@ -3,17 +3,13 @@ import UIKit
 /// AnimatedImageCache is an image + animated gif data cache used in
 /// CachedAnimatedImageView. It should be accessed via the `shared` singleton.
 ///
-class AnimatedImageCache {
+final class AnimatedImageCache {
 
     // MARK: Singleton
 
     static let shared: AnimatedImageCache = AnimatedImageCache()
-    private init() {
-        NotificationCenter.default.addObserver(self,
-                                               selector: #selector(AnimatedImageCache.handleMemoryWarning),
-                                               name: UIApplication.didReceiveMemoryWarningNotification,
-                                               object: nil)
-    }
+
+    private init() {}
 
     // MARK: Private fields
 
@@ -23,50 +19,30 @@ class AnimatedImageCache {
         return session
     }()
 
-    fileprivate static var cache: NSCache<AnyObject, AnyObject> = {
-        let cache = NSCache<AnyObject, AnyObject>()
-        cache.totalCostLimit = totalCostLimit()
-
-        let bcf = ByteCountFormatter()
-        bcf.allowedUnits = [.useMB]
-        bcf.countStyle = .file
-        let cacheSizeinMB = bcf.string(fromByteCount: Int64(totalCostLimit()))
-
-        return cache
-    }()
-
     // MARK: Instance methods
 
-    @objc func handleMemoryWarning() {
-        clearCache()
-    }
-
-    func clearCache() {
-        AnimatedImageCache.cache.removeAllObjects()
+    func cacheData(data: Data, url: URL?) {
+        guard let url else { return }
+        let key = url.absoluteString + Constants.keyDataSuffix
+        MemoryCache.shared.setData(data, forKey: key)
     }
 
     func cachedData(url: URL?) -> Data? {
-        guard let key = url else {
-            return nil
-        }
-        return AnimatedImageCache.cache.object(forKey: key as AnyObject) as? Data
+        guard let url else { return nil }
+        let key = url.absoluteString + Constants.keyDataSuffix
+        return MemoryCache.shared.geData(forKey: key)
     }
 
     func cacheStaticImage(url: URL?, image: UIImage?) {
-        guard let url = url,
-            let image = image else {
-                return
-        }
+        guard let url, let image else { return }
         let key = url.absoluteString + Constants.keyStaticImageSuffix
-        AnimatedImageCache.cache.setObject(image as AnyObject, forKey: key as AnyObject)
+        MemoryCache.shared.setImage(image, forKey: key)
     }
 
     func cachedStaticImage(url: URL?) -> UIImage? {
-        guard let url = url else {
-            return nil
-        }
+        guard let url else { return nil }
         let key = url.absoluteString + Constants.keyStaticImageSuffix
-        return AnimatedImageCache.cache.object(forKey: key as AnyObject) as? UIImage
+        return MemoryCache.shared.getImage(forKey: key)
     }
 
     func animatedImage(_ urlRequest: URLRequest,
@@ -81,7 +57,7 @@ class AnimatedImageCache {
 
         let task = session.dataTask(with: urlRequest, completionHandler: { [weak self] (data, response, error) in
             //check if view is still here
-            guard let _ = self else {
+            guard let self = self else {
                 return
             }
             // check if there is an error
@@ -101,13 +77,8 @@ class AnimatedImageCache {
 
             let staticImage = UIImage(data: data)
             if let key = urlRequest.url {
-                let dataByteCost = AnimatedImageCache.byteCost(for: data)
-                AnimatedImageCache.cache.setObject(data as NSData, forKey: key as NSURL, cost: dataByteCost)
-
-                // Creating a static image from GIF data is an expensive op, so let's try to do it once...
-                let imageByteCost = AnimatedImageCache.byteCost(for: staticImage)
-                let imageKey = key.absoluteString + Constants.keyStaticImageSuffix
-                AnimatedImageCache.cache.setObject(staticImage as AnyObject, forKey: imageKey as AnyObject, cost: imageByteCost)
+                self.cacheData(data: data, url: key)
+                self.cacheStaticImage(url: key, image: staticImage)
             }
             success?(data, staticImage)
         })
@@ -117,38 +88,11 @@ class AnimatedImageCache {
     }
 }
 
-// MARK: - Private Helpers
-
-private extension AnimatedImageCache {
-    static func byteCost(for image: UIImage?) -> Int {
-        guard let image = image, let imageRef = image.cgImage else {
-            return 0
-        }
-        return imageRef.bytesPerRow * imageRef.height // Cost in bytes
-    }
-
-    static func byteCost(for data: Data?) -> Int {
-        guard let data = data else {
-            return 0
-        }
-        return data.count // Cost in bytes
-    }
-
-    static func totalCostLimit() -> Int {
-        let physicalMemory = ProcessInfo.processInfo.physicalMemory
-        let cacheRatio = physicalMemory <= (Constants.memory512MB) ? Constants.smallCacheRatio : Constants.largeCacheRatio
-        let cacheLimit = physicalMemory / UInt64(1 / cacheRatio)
-        return cacheLimit > UInt64(Int.max) ? Int.max : Int(cacheLimit)
-    }
-}
-
 // MARK: - Constants
 
 private extension AnimatedImageCache {
     struct Constants {
+        static let keyDataSuffix = "_data"
         static let keyStaticImageSuffix = "_static_image"
-        static let memory512MB: UInt64 = 1024 * 1024 * 512 // 512 Mb
-        static let smallCacheRatio: CGFloat = 0.1
-        static let largeCacheRatio: CGFloat = 0.2
     }
 }

WordPress/Classes/ViewRelated/Media/MemoryCache.swift

@@ -0,0 +1,118 @@
+import Foundation
+import AlamofireImage
+import WordPressUI
+import SDWebImage
+
+final class MemoryCache {
+    /// A shared image cache used by the entire system.
+    static let shared = MemoryCache()
+
+    private let cache = NSCache<NSString, AnyObject>()
+
+    private init() {
+        self.cache.totalCostLimit = 256_000_000 // 256 MB
+
+        NotificationCenter.default.addObserver(self, selector: #selector(didReceiveMemoryWarning), name: UIApplication.didReceiveMemoryWarningNotification, object: nil)
+    }
+
+    @objc private func didReceiveMemoryWarning() {
+        cache.removeAllObjects()
+    }
+
+    // MARK: - UIImage
+
+    func setImage(_ image: UIImage, forKey key: String) {
+        cache.setObject(image, forKey: key as NSString, cost: Int(image.sd_memoryCost))
+    }
+
+    func getImage(forKey key: String) -> UIImage? {
+        cache.object(forKey: key as NSString) as? UIImage
+    }
+
+    func removeImage(forKey key: String) {
+        cache.removeObject(forKey: key as NSString)
+    }
+
+    // MARK: - Data
+
+    func setData(_ data: Data, forKey key: String) {
+        cache.setObject(data as NSData, forKey: key as NSString, cost: data.count)
+    }
+
+    func geData(forKey key: String) -> Data? {
+        cache.object(forKey: key as NSString) as? Data
+    }
+
+    func removeData(forKey key: String) {
+        cache.removeObject(forKey: key as NSString)
+    }
+}
+
+extension MemoryCache {
+    /// Registers the cache with all the image loading systems used by the app.
+    func register() {
+        // WordPressUI
+        WordPressUI.ImageCache.shared = WordpressUICacheAdapter(cache: .shared)
+
+        // AlamofireImage
+        UIImageView.af_sharedImageDownloader = AlamofireImage.ImageDownloader(
+            imageCache: AlamofireImageCacheAdapter(cache: .shared)
+        )
+
+        // WordPress.AnimatedImageCache uses WordPress.MemoryCache directly
+    }
+}
+
+private struct WordpressUICacheAdapter: WordPressUI.ImageCaching {
+    let cache: MemoryCache
+
+    func setImage(_ image: UIImage, forKey key: String) {
+        cache.setImage(image, forKey: key)
+    }
+
+    func getImage(forKey key: String) -> UIImage? {
+        cache.getImage(forKey: key)
+    }
+}
+
+private struct AlamofireImageCacheAdapter: AlamofireImage.ImageRequestCache {
+    let cache: MemoryCache
+
+    func image(for request: URLRequest, withIdentifier identifier: String?) -> AlamofireImage.Image? {
+        image(withIdentifier: cacheKey(for: request, identifier: identifier))
+    }
+
+    func add(_ image: AlamofireImage.Image, for request: URLRequest, withIdentifier identifier: String?) {
+        add(image, withIdentifier: cacheKey(for: request, identifier: identifier))
+    }
+
+    func removeImage(for request: URLRequest, withIdentifier identifier: String?) -> Bool {
+        removeImage(withIdentifier: cacheKey(for: request, identifier: identifier))
+    }
+
+    func image(withIdentifier identifier: String) -> AlamofireImage.Image? {
+        cache.getImage(forKey: identifier)
+    }
+
+    func add(_ image: AlamofireImage.Image, withIdentifier identifier: String) {
+        cache.setImage(image, forKey: identifier)
+    }
+
+    func removeImage(withIdentifier identifier: String) -> Bool {
+        cache.removeImage(forKey: identifier)
+        return true
+    }
+
+    func removeAllImages() -> Bool {
+        // Do nothing (the app decides when to remove images)
+        return true
+    }
+
+    private func cacheKey(for request: URLRequest, identifier: String?) -> String {
+        var key = request.url?.absoluteString ?? ""
+        if let identifier = identifier {
+            key += "-\(identifier)"
+        }
+        return key
+    }
+}

WordPress/Classes/ViewRelated/Menus/MenusViewController.m

@@ -14,7 +14,6 @@
 #import "WordPress-Swift.h"
 #import <WordPressShared/WPFontManager.h>
 #import <WordPressShared/WPStyleGuide.h>
-#import <WordPressUI/WordPressUI.h>
 
 
 

WordPress/Classes/ViewRelated/Post/FeaturedImageViewController.m

@@ -2,7 +2,6 @@
 
 #import "Media.h"
 #import "WordPress-Swift.h"
-#import <WordPressUI/WordPressUI.h>
 
 
 @interface FeaturedImageViewController ()