Refactor ETag cache API

source/net/filebot/Cache.java

@@ -45,9 +45,19 @@ public class Cache {
 	}
 
 	private final net.sf.ehcache.Cache cache;
+	private final CacheType cacheType;
 
-	public Cache(net.sf.ehcache.Cache cache) {
+	public Cache(net.sf.ehcache.Cache cache, CacheType cacheType) {
 		this.cache = cache;
+		this.cacheType = cacheType;
+	}
+
+	public String getName() {
+		return cache.getName();
+	}
+
+	public CacheType getCacheType() {
+		return cacheType;
 	}
 
 	public Object get(Object key) {
@@ -123,15 +133,15 @@ public class Cache {
 	}
 
 	public <V> TypedCache<V> typed(Function<Object, V> read, Function<V, Object> write) {
-		return new TypedCache<V>(cache, read, write);
+		return new TypedCache<V>(cache, cacheType, read, write);
 	}
 
 	public <V> TypedCache<V> cast(Class<V> cls) {
-		return new TypedCache<V>(cache, it -> cls.cast(it), it -> it);
+		return new TypedCache<V>(cache, cacheType, it -> cls.cast(it), it -> it);
 	}
 
 	public <V> TypedCache<List<V>> castList(Class<V> cls) {
-		return new TypedCache<List<V>>(cache, it -> it == null ? null : stream((Object[]) it).map(cls::cast).collect(toList()), it -> it == null ? null : it.toArray());
+		return new TypedCache<List<V>>(cache, cacheType, it -> it == null ? null : stream((Object[]) it).map(cls::cast).collect(toList()), it -> it == null ? null : it.toArray());
 	}
 
 	@SuppressWarnings("unchecked")
@@ -140,8 +150,8 @@ public class Cache {
 		private final Function<Object, V> read;
 		private final Function<V, Object> write;
 
-		public TypedCache(net.sf.ehcache.Cache cache, Function<Object, V> read, Function<V, Object> write) {
-			super(cache);
+		public TypedCache(net.sf.ehcache.Cache cache, CacheType cacheType, Function<Object, V> read, Function<V, Object> write) {
+			super(cache, cacheType);
 			this.read = read;
 			this.write = write;
 		}

source/net/filebot/CacheManager.java

@@ -42,7 +42,7 @@ public class CacheManager {
 		if (!manager.cacheExists(name)) {
 			manager.addCache(new net.sf.ehcache.Cache(type.getConfiguration(name)));
 		}
-		return new Cache(manager.getCache(name));
+		return new Cache(manager.getCache(name), type);
 	}
 
 	public synchronized void clearAll() {

source/net/filebot/CachedResource.java

@@ -15,6 +15,7 @@ import java.util.concurrent.Callable;
 import java.util.function.BiConsumer;
 import java.util.function.Consumer;
 import java.util.function.Function;
+import java.util.function.Predicate;
 import java.util.function.Supplier;
 
 import org.w3c.dom.Document;
@@ -189,21 +190,41 @@ public class CachedResource<K, R> implements Resource<R> {
 		};
 	}
 
+	public static Fetch fetchIfNoneMatch(Transform<URL, ?> key, Cache cache) {
+		// create cache with the same config
+		Cache etagStorage = Cache.getCache(cache.getName() + "_etag", cache.getCacheType());
+
+		// make sure value cache contains key, otherwise ignore previously stored etag
+		return fetchIfNoneMatch(url -> {
+			try {
+				return cache.get(key.transform(url)) == null ? null : etagStorage.get(key.transform(url));
+			} catch (Exception e) {
+				throw new RuntimeException(e);
+			}
+		}, (url, etag) -> {
+			try {
+				etagStorage.put(key.transform(url), etag);
+			} catch (Exception e) {
+				throw new RuntimeException(e);
+			}
+		});
+	}
+
 	public static Fetch fetchIfNoneMatch(Function<URL, Object> etagRetrieve, BiConsumer<URL, String> etagStore) {
 		return (url, lastModified) -> {
 			Object etagValue = etagRetrieve.apply(url);
 			debug.fine(WebRequest.log(url, lastModified, etagValue));
 			try {
-				return WebRequest.fetch(url, etagValue == null ? lastModified : 0, etagValue, null, storeETag(url, etagStore));
+				return WebRequest.fetch(url, etagValue == null ? lastModified : 0, etagValue, null, storeETag(url, etagStore, etag -> !etag.equals(etagValue)));
 			} catch (FileNotFoundException e) {
 				return fileNotFound(url, e);
 			}
 		};
 	}
 
-	private static Consumer<Map<String, List<String>>> storeETag(URL url, BiConsumer<URL, String> etagStore) {
+	private static Consumer<Map<String, List<String>>> storeETag(URL url, BiConsumer<URL, String> etagStore, Predicate<String> etagFilter) {
 		return (responseHeaders) -> {
-			WebRequest.getETag(responseHeaders).ifPresent(etag -> {
+			WebRequest.getETag(responseHeaders).filter(etagFilter).ifPresent(etag -> {
 				debug.finest(format("Store ETag: %s", etag));
 				etagStore.accept(url, etag);
 			});

source/net/filebot/web/TMDbClient.java

@@ -33,7 +33,6 @@ import javax.swing.Icon;
 
 import net.filebot.Cache;
 import net.filebot.CacheType;
-import net.filebot.CachedResource.Fetch;
 import net.filebot.Language;
 import net.filebot.ResourceManager;
 import net.filebot.web.TMDbClient.MovieInfo.MovieProperty;
@@ -297,11 +296,8 @@ public class TMDbClient implements MovieIdentificationService, ArtworkProvider {
 		String key = parameters.isEmpty() ? resource : resource + '?' + encodeParameters(parameters, true);
 		String cacheName = locale.getLanguage().isEmpty() ? getName() : getName() + "_" + locale;
 
-		Cache etagStorage = Cache.getCache(cacheName + "_etag", CacheType.Monthly);
 		Cache cache = Cache.getCache(cacheName, CacheType.Monthly);
-
-		Fetch fetchIfNoneMatch = fetchIfNoneMatch(url -> cache.get(key) == null ? null : etagStorage.get(key), (url, etag) -> etagStorage.put(key, etag));
-		Object json = cache.json(key, s -> getResource(s, locale)).fetch(withPermit(fetchIfNoneMatch, r -> limit.acquirePermit())).expire(Cache.ONE_WEEK).get();
+		Object json = cache.json(key, k -> getResource(k, locale)).fetch(withPermit(fetchIfNoneMatch(url -> key, cache), r -> limit.acquirePermit())).expire(Cache.ONE_WEEK).get();
 
 		if (asMap(json).isEmpty()) {
 			throw new FileNotFoundException(String.format("Resource is empty: %s => %s", json, getResource(key, locale)));