Cache unavailable URI's

Fixes eclipse-lemminx#201

Signed-off-by: Nikolas Komonen <[email protected]>

org.eclipse.lsp4xml/pom.xml

@@ -103,5 +103,10 @@
 			<artifactId>junit</artifactId>
 			<scope>test</scope>
 		</dependency>
+		<dependency>
+			<groupId>com.github.ben-manes.caffeine</groupId>
+			<artifactId>caffeine</artifactId>
+			<version>2.5.5</version>
+		</dependency>
 	</dependencies>
 </project>

org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/uriresolver/CacheResourcesManager.java

@@ -27,9 +27,13 @@
 import java.util.HashMap;
 import java.util.Map;
 import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.TimeUnit;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import com.github.benmanes.caffeine.cache.Cache;
+import com.github.benmanes.caffeine.cache.Caffeine;
+
 import org.eclipse.lsp4xml.utils.FilesUtils;
 import org.eclipse.lsp4xml.utils.URIUtils;
 
@@ -38,6 +42,10 @@
  *
  */
 public class CacheResourcesManager {
+	private final Cache<String, Boolean> unavailableURICache = Caffeine.newBuilder()
+																			   .expireAfterWrite(1, TimeUnit.MINUTES)
+																			   .maximumSize(100)
+																			   .build();
 
 	private static final String CACHE_PATH = "cache";
 	private static final Logger LOGGER = Logger.getLogger(CacheResourcesManager.class.getName());
@@ -83,10 +91,16 @@ public CacheResourcesManager() {
 	}
 
 	public Path getResource(final String resourceURI) throws IOException {
+		LOGGER.info("DELETE THIS !@#");
 		Path resourceCachePath = getResourceCachePath(resourceURI);
 		if (Files.exists(resourceCachePath)) {
 			return resourceCachePath;
 		}
+
+		if(unavailableURICache.getIfPresent(resourceURI) != null) {
+			return null;
+		}
+
 		CompletableFuture<Path> f = null;
 		synchronized (resourcesLoading) {
 			if (resourcesLoading.containsKey(resourceURI)) {
@@ -139,11 +153,12 @@ private CompletableFuture<Path> downloadResource(final String resourceURI, Path
 				LOGGER.info("Downloaded " + resourceURI + " to " + resourceCachePath + " in " + elapsed + "ms");
 			} catch (Exception e) {
 				// Do nothing
+				unavailableURICache.put(resourceURI, true);
 				Throwable rootCause = getRootCause(e);
 				String error = "[" + rootCause.getClass().getTypeName() + "] " + rootCause.getMessage();
 				LOGGER.log(Level.SEVERE,
 						"Error while downloading " + resourceURI + " to " + resourceCachePath + " : " + error);
-				throw new CacheResourceDownloadedException("Error while downloading '" + resourceURI + "'.", e);
+				throw new CacheResourceDownloadedException("Error while downloading '" + resourceURI + "' to " + resourceCachePath + ".", e);
 			} finally {
 				synchronized (resourcesLoading) {
 					resourcesLoading.remove(resourceURI);

org.eclipse.lsp4xml/src/test/java/org/eclipse/lsp4xml/uriresolver/CacheResourcesManagerTest.java

@@ -12,6 +12,9 @@
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+
+import java.io.IOException;
 
 import org.junit.Test;
 
@@ -32,4 +35,9 @@ private void testCanUseCache(boolean useCacheEnabled) {
 		assertFalse(cacheResourcesManager.canUseCache("file:///foo"));
 	}
 
+	@Test
+	public void testUnavailableCache() {
+
+	}
+
 }