Start FeedIconDownloader.

Evergreen.xcodeproj/project.pbxproj

@@ -7,6 +7,7 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		8426118A1FCB67AA0086A189 /* FeedIconDownloader.swift in Sources */ = {isa = PBXBuildFile; fileRef = 842611891FCB67AA0086A189 /* FeedIconDownloader.swift */; };
 		842E45CE1ED8C308000A8B52 /* AppNotifications.swift in Sources */ = {isa = PBXBuildFile; fileRef = 842E45CD1ED8C308000A8B52 /* AppNotifications.swift */; };
 		842E45DD1ED8C54B000A8B52 /* Browser.swift in Sources */ = {isa = PBXBuildFile; fileRef = 842E45DC1ED8C54B000A8B52 /* Browser.swift */; };
 		842E45E31ED8C681000A8B52 /* KeyboardDelegateProtocol.swift in Sources */ = {isa = PBXBuildFile; fileRef = 842E45E21ED8C681000A8B52 /* KeyboardDelegateProtocol.swift */; };
@@ -403,6 +404,7 @@
 /* End PBXCopyFilesBuildPhase section */
 
 /* Begin PBXFileReference section */
+		842611891FCB67AA0086A189 /* FeedIconDownloader.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = FeedIconDownloader.swift; sourceTree = "<group>"; };
 		842E45CD1ED8C308000A8B52 /* AppNotifications.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; name = AppNotifications.swift; path = Evergreen/AppNotifications.swift; sourceTree = "<group>"; };
 		842E45DC1ED8C54B000A8B52 /* Browser.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; name = Browser.swift; path = Evergreen/Browser.swift; sourceTree = "<group>"; };
 		842E45E21ED8C681000A8B52 /* KeyboardDelegateProtocol.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = KeyboardDelegateProtocol.swift; sourceTree = "<group>"; };
@@ -567,6 +569,7 @@
 			children = (
 				845213221FCA5B10003B6E93 /* ImageDownloader.swift */,
 				84E850851FCB60CE0072EA88 /* AuthorAvatarDownloader.swift */,
+				842611891FCB67AA0086A189 /* FeedIconDownloader.swift */,
 			);
 			name = Images;
 			path = Evergreen/Images;
@@ -1349,6 +1352,7 @@
 				849A97651ED9EB96007D329B /* SidebarTreeControllerDelegate.swift in Sources */,
 				849A97671ED9EB96007D329B /* UnreadCountView.swift in Sources */,
 				84AFBB3C1FBE76D800BA41CF /* PanicButtonWindowController.swift in Sources */,
+				8426118A1FCB67AA0086A189 /* FeedIconDownloader.swift in Sources */,
 				84E95D241FB1087500552D99 /* ArticlePasteboardWriter.swift in Sources */,
 				84A6B6961FB8DBD2006754AC /* DinosaursWindowController.swift in Sources */,
 				849A975B1ED9EB0D007D329B /* ArticleUtilities.swift in Sources */,

Evergreen/Images/FeedIconDownloader.swift

@@ -0,0 +1,119 @@
+//
+//  FeedIconDownloader.swift
+//  Evergreen
+//
+//  Created by Brent Simmons on 11/26/17.
+//  Copyright © 2017 Ranchero Software. All rights reserved.
+//
+
+import Cocoa
+import Data
+import RSWeb
+import RSParser
+
+public final class FeedIconDownloader {
+
+	private let imageDownloader: ImageDownloader
+	private var homePageToIconURLCache = [String: String]()
+
+	init(imageDownloader: ImageDownloader) {
+
+		self.imageDownloader = imageDownloader
+	}
+
+	func icon(for feed: Feed) -> NSImage? {
+
+		if let iconURL = feed.iconURL {
+			return icon(forURL: iconURL)
+		}
+
+		if let homePageURL = feed.homePageURL {
+			return icon(forHomePageURL: homePageURL)
+		}
+
+		return nil
+	}
+
+	func icon(forHomePageURL homePageURL: String) -> NSImage? {
+
+		if let iconURL = cachedIconURL(for: homePageURL) {
+			return icon(forURL: iconURL)
+		}
+		
+		findIconURLForHomePageURL(homePageURL)
+		return nil
+	}
+
+	func icon(forURL url: String) -> NSImage? {
+
+		return imageDownloader.image(for: url)
+	}
+}
+
+private extension FeedIconDownloader {
+
+	func cachedIconURL(for homePageURL: String) -> String? {
+
+		return homePageToIconURLCache[homePageURL]
+	}
+
+	func cacheIconURL(for homePageURL: String, _ iconURL: String) {
+
+		homePageToIconURLCache[homePageURL] = iconURL
+	}
+
+	func findIconURLForHomePageURL(_ homePageURL: String) {
+
+		guard let url = URL(string: homePageURL) else {
+			return
+		}
+
+		downloadUsingCache(url) { (data, response, error) in
+
+			if let data = data, !data.isEmpty, let response = response, response.statusIsOK, error == nil {
+
+				let parserData = ParserData(url: homePageURL, data: data)
+				let metadata = RSHTMLMetadataParser.htmlMetadata(with: parserData)
+				self.pullIconURL(from: metadata, homePageURL: homePageURL)
+				return
+			}
+
+			if let error = error {
+				appDelegate.logMessage("Error finding icon url at \(homePageURL): \(error)", type: .warning)
+			}
+		}
+	}
+
+	func pullIconURL(from metadata: RSHTMLMetadata, homePageURL: String) {
+
+		if let openGraphImageURL = largestOpenGraphImageURL(from: metadata) {
+			cacheIconURL(for: homePageURL, openGraphImageURL)
+			return
+		}
+
+		if let twitterImageURL = metadata.twitterProperties.imageURL {
+			cacheIconURL(for: homePageURL, twitterImageURL)
+		}
+	}
+
+	func largestOpenGraphImageURL(from metadata: RSHTMLMetadata) -> String? {
+
+		guard let openGraphImages = metadata.openGraphProperties?.images else {
+			return nil
+		}
+
+		var bestImage: RSHTMLOpenGraphImage? = nil
+
+		for image in openGraphImages {
+			if bestImage == nil {
+				bestImage = image
+				continue
+			}
+			if image.height > bestImage!.height && image.width > bestImage!.width {
+				bestImage = image
+			}
+		}
+
+		return bestImage?.secureURL ?? bestImage?.url
+	}
+}

Frameworks/RSWeb/RSWeb/OneShotDownload.swift

@@ -114,8 +114,8 @@ private final class DownloadWithCacheManager {
 
 	static let shared = DownloadWithCacheManager()
 	private var cache = WebCache()
-	private static let timeToLive: TimeInterval = 5 * 60 // five minutes
-	private static let cleanupInterval: TimeInterval = 20 * 60 // 20 minutes
+	private static let timeToLive: TimeInterval = 10 * 60 // 10 minutes
+	private static let cleanupInterval: TimeInterval = 30 * 60 // 30 minutes
 
 	func download(_ url: URL, _ callback: @escaping OneShotDownloadCallback) {