Use DTD/XML Schema cache manager for completion

This PR uses like validation the cache manager to load the DTD/XML
Schema content model used for completion based on grammar, hover. It
should fix the performance problem of #397

Signed-off-by: azerr <[email protected]>

org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/extensions/contentmodel/model/ContentModelManager.java

@@ -10,6 +10,7 @@
  */
 package org.eclipse.lsp4xml.extensions.contentmodel.model;
 
+import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -22,6 +23,7 @@
 import org.eclipse.lsp4xml.extensions.contentmodel.uriresolver.XMLCacheResolverExtension;
 import org.eclipse.lsp4xml.extensions.contentmodel.uriresolver.XMLCatalogResolverExtension;
 import org.eclipse.lsp4xml.extensions.contentmodel.uriresolver.XMLFileAssociationResolverExtension;
+import org.eclipse.lsp4xml.uriresolver.CacheResourceDownloadingException;
 import org.eclipse.lsp4xml.uriresolver.URIResolverExtensionManager;
 import org.eclipse.lsp4xml.utils.URIUtils;
 
@@ -114,7 +116,23 @@ private CMDocument findCMDocument(String uri, String publicId, String systemId,
 			cmDocument = cmDocumentCache.get(key);
 		}
 		if (cmDocument == null) {
-			cmDocument = modelProvider.createCMDocument(key);
+			if (isCacheable && cacheResolverExtension.isUseCache()) {
+				// Try to load the DTD/XML Schema with the cache manager
+				try {
+					Path file = cacheResolverExtension.getCachedResource(key);
+					if (file != null) {
+						cmDocument = modelProvider.createCMDocument(file.toFile().getPath());
+					}
+				} catch (CacheResourceDownloadingException e) {
+					// the DTD/XML Schema is downloading
+					return null;
+				} catch (Exception e) {
+					// other error like network which is not available
+					cmDocument = modelProvider.createCMDocument(key);
+				}
+			} else {
+				cmDocument = modelProvider.createCMDocument(key);
+			}
 			if (isCacheable && cmDocument != null) {
 				cmDocumentCache.put(key, cmDocument);
 			}

org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/extensions/contentmodel/uriresolver/XMLCacheResolverExtension.java

@@ -17,6 +17,7 @@
 import org.apache.xerces.xni.XMLResourceIdentifier;
 import org.apache.xerces.xni.XNIException;
 import org.apache.xerces.xni.parser.XMLInputSource;
+import org.eclipse.lsp4xml.uriresolver.CacheResourceDownloadedException;
 import org.eclipse.lsp4xml.uriresolver.CacheResourcesManager;
 import org.eclipse.lsp4xml.uriresolver.URIResolverExtension;
 
@@ -44,18 +45,34 @@ public String resolve(String baseLocation, String publicId, String systemId) {
 	@Override
 	public XMLInputSource resolveEntity(XMLResourceIdentifier resourceIdentifier) throws XNIException, IOException {
 		String url = resourceIdentifier.getExpandedSystemId();
+		// Try to get the downloaded resource. In the case where the resource is
+		// downloading but takes too long, a CacheResourceDownloadingException is
+		// thrown.
+		Path file = getCachedResource(url);
+		if (file != null) {
+			// The resource was downloaded locally, use it.
+			XMLInputSource source = new XMLInputSource(resourceIdentifier);
+			source.setByteStream(Files.newInputStream(file));
+			return source;
+		}
+		return null;
+	}
+
+	/**
+	 * Returns the cached resource path from the given url and null otherwise.
+	 * 
+	 * @param url the url
+	 * @return the cached resource path from the given url and null otherwise.
+	 * @throws IOException
+	 * @throws CacheResourceDownloadedException throws when resource is downloading.
+	 */
+	public Path getCachedResource(String url) throws IOException, CacheResourceDownloadedException {
 		// Cache is used only for resource coming from "http(s)" or "ftp".
 		if (cacheResourcesManager.canUseCache(url)) {
 			// Try to get the downloaded resource. In the case where the resource is
 			// downloading but takes too long, a CacheResourceDownloadingException is
 			// thrown.
-			Path file = cacheResourcesManager.getResource(url);
-			if (file != null) {
-				// The resource was downloaded locally, use it.
-				XMLInputSource source = new XMLInputSource(resourceIdentifier);
-				source.setByteStream(Files.newInputStream(file));
-				return source;
-			}
+			return cacheResourcesManager.getResource(url);
 		}
 		return null;
 	}
@@ -70,4 +87,15 @@ public void setUseCache(boolean useCache) {
 		cacheResourcesManager.setUseCache(useCache);
 	}
 
+	/**
+	 * Returns <code>true</code> if cache must be used, <code>false</code>
+	 * otherwise.
+	 * 
+	 * @return <code>true</code> if cache must be used, <code>false</code>
+	 *         otherwise.
+	 */
+	public boolean isUseCache() {
+		return cacheResourcesManager.isUseCache();
+	}
+
 }

org.eclipse.lsp4xml/src/test/java/org/eclipse/lsp4xml/extensions/contentmodel/DTDCompletionWithCacheExtensionsTest.java

@@ -0,0 +1,72 @@
+/**
+ *  Copyright (c) 2019 Red Hat, Inc. and others.
+ *  All rights reserved. This program and the accompanying materials
+ *  are made available under the terms of the Eclipse Public License v2.0
+ *  which accompanies this distribution, and is available at
+ *  http://www.eclipse.org/legal/epl-v20.html
+ *
+ *  Contributors:
+ *  Red Hat Inc. - initial API and implementation
+ */
+package org.eclipse.lsp4xml.extensions.contentmodel;
+
+import static org.eclipse.lsp4xml.XMLAssert.c;
+import static org.eclipse.lsp4xml.XMLAssert.te;
+
+import java.io.FileOutputStream;
+import java.nio.channels.Channels;
+import java.nio.channels.ReadableByteChannel;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.function.Consumer;
+
+import org.eclipse.lsp4xml.AbstractCacheBasedTest;
+import org.eclipse.lsp4xml.XMLAssert;
+import org.eclipse.lsp4xml.extensions.contentmodel.model.ContentModelManager;
+import org.eclipse.lsp4xml.services.XMLLanguageService;
+import org.junit.Test;
+
+/**
+ * Test with DTD completion and cache.
+ * 
+ * @author Angelo ZERR
+ *
+ */
+public class DTDCompletionWithCacheExtensionsTest extends AbstractCacheBasedTest {
+
+	@Test
+	public void dtdCache() throws Exception {
+		Consumer<XMLLanguageService> configuration = ls -> {
+			ContentModelManager contentModelManager = ls.getComponent(ContentModelManager.class);
+			// Use cache on file system
+			contentModelManager.setUseCache(true);
+		};
+
+		// Copy the svg.dtd in the cache folder
+		Path expectedLocation = TEST_WORK_DIRECTORY
+				.resolve("cache/http/www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd");
+		// Download resource in a temporary file
+		Files.createDirectories(expectedLocation.getParent());
+		Path path = Files.createFile(expectedLocation);
+
+		try (ReadableByteChannel rbc = Channels
+				.newChannel(DTDCompletionWithCacheExtensionsTest.class.getResourceAsStream("/dtd/svg.dtd"));
+				FileOutputStream fos = new FileOutputStream(path.toFile())) {
+			fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+		}
+
+		// Execute completion based on svg.dtd by using the cache manager
+		String fileURI = "test.xml";
+		String xml = "<?xml version=\"1.0\" standalone=\"no\" ?>\r\n" + //
+				"<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 1.0//EN\" \"http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd\">\r\n"
+				+ //
+				"<svg xmlns=\"http://www.w3.org/2000/svg\">\r\n" + //
+				"    <animate attributeName=\"foo\">\r\n" + //
+				"        |\r\n"; // <- completion";
+
+		XMLLanguageService ls = new XMLLanguageService();
+		XMLAssert.testCompletionFor(ls, xml, null, configuration, fileURI, null, true,
+				c("desc", te(4, 8, 4, 8, "<desc></desc>"), "desc"));
+	}
+
+}