Disable XSD validation when xsi:schemaLocation doesn't declare the

namespace for the document element root.

See #951

Signed-off-by: azerr <azerr@redhat.com>

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/ContentModelPlugin.java

@@ -12,6 +12,8 @@
  */
 package org.eclipse.lemminx.extensions.contentmodel;
 
+import java.util.Objects;
+
 import org.eclipse.lemminx.dom.DOMDocument;
 import org.eclipse.lemminx.extensions.contentmodel.commands.XMLValidationAllFilesCommand;
 import org.eclipse.lemminx.extensions.contentmodel.commands.XMLValidationFileCommand;
@@ -24,6 +26,7 @@
 import org.eclipse.lemminx.extensions.contentmodel.participants.ContentModelTypeDefinitionParticipant;
 import org.eclipse.lemminx.extensions.contentmodel.participants.diagnostics.ContentModelDiagnosticsParticipant;
 import org.eclipse.lemminx.extensions.contentmodel.settings.ContentModelSettings;
+import org.eclipse.lemminx.extensions.contentmodel.settings.XMLValidationSettings;
 import org.eclipse.lemminx.services.IXMLDocumentProvider;
 import org.eclipse.lemminx.services.IXMLValidationService;
 import org.eclipse.lemminx.services.extensions.ICodeActionParticipant;
@@ -69,6 +72,8 @@ public class ContentModelPlugin implements IXMLExtension {
 
 	private ContentModelSettings cmSettings;
 
+	private XMLValidationSettings currentValidationSettings;
+
 	public ContentModelPlugin() {
 		completionParticipant = new ContentModelCompletionParticipant();
 		hoverParticipant = new ContentModelHoverParticipant();
@@ -105,6 +110,8 @@ private void updateSettings(ISaveContext saveContext) {
 		cmSettings = ContentModelSettings.getContentModelXMLSettings(initializationOptionsSettings);
 		if (cmSettings != null) {
 			updateSettings(cmSettings, saveContext);
+		} else {
+			currentValidationSettings = null;
 		}
 	}
 
@@ -144,6 +151,12 @@ private void updateSettings(ContentModelSettings settings, ISaveContext context)
 		// Update symbols
 		boolean showReferencedGrammars = settings.isShowReferencedGrammars();
 		symbolsProviderParticipant.setEnabled(showReferencedGrammars);
+		// Track if validation settings has changed
+		XMLValidationSettings oldValidationSettings = currentValidationSettings;
+		currentValidationSettings = cmSettings.getValidation();
+		if (oldValidationSettings != null && !Objects.equals(oldValidationSettings, currentValidationSettings)) {
+			context.collectDocumentToValidate(d -> true);
+		}
 	}
 
 	@Override

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/participants/diagnostics/XMLValidator.java

@@ -13,23 +13,31 @@
 package org.eclipse.lemminx.extensions.contentmodel.participants.diagnostics;
 
 import java.io.IOException;
+import java.io.InputStream;
 import java.io.StringReader;
+import java.net.URL;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.CancellationException;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import org.apache.xerces.impl.XMLEntityManager;
 import org.apache.xerces.parsers.SAXParser;
+import org.apache.xerces.util.URI.MalformedURIException;
 import org.apache.xerces.xni.grammars.XMLGrammarPool;
 import org.apache.xerces.xni.parser.XMLEntityResolver;
 import org.eclipse.lemminx.dom.DOMAttr;
 import org.eclipse.lemminx.dom.DOMDocument;
 import org.eclipse.lemminx.dom.DOMDocumentType;
 import org.eclipse.lemminx.dom.DOMElement;
+import org.eclipse.lemminx.dom.NoNamespaceSchemaLocation;
+import org.eclipse.lemminx.dom.SchemaLocationHint;
 import org.eclipse.lemminx.extensions.contentmodel.model.ContentModelManager;
 import org.eclipse.lemminx.extensions.contentmodel.participants.XMLSyntaxErrorCode;
+import org.eclipse.lemminx.extensions.contentmodel.settings.SchemaEnabled;
+import org.eclipse.lemminx.extensions.contentmodel.settings.XMLSchemaSettings;
 import org.eclipse.lemminx.extensions.contentmodel.settings.XMLValidationSettings;
 import org.eclipse.lemminx.services.extensions.diagnostics.LSPContentHandler;
 import org.eclipse.lemminx.uriresolver.CacheResourceDownloadingException;
@@ -82,19 +90,24 @@ public static void doDiagnostics(DOMDocument document, XMLEntityResolver entityR
 			// Add LSP content handler to stop XML parsing if monitor is canceled.
 			parser.setContentHandler(new LSPContentHandler(monitor));
 
-			boolean hasSchemaGrammar = document.hasSchemaLocation() || document.hasNoNamespaceSchemaLocation()
-					|| hasExternalSchemaGrammar(document);
-			boolean hasGrammar = document.hasDTD() || hasSchemaGrammar || document.hasExternalGrammar();
-			// If diagnostics for Schema preference is enabled
-			if ((validationSettings == null) || validationSettings.isSchema()) {
+			// warn if XML document is not bound to a grammar according the settings
+			warnNoGrammar(document, diagnostics, validationSettings);
+			// Update external grammar location (file association)
+			updateExternalGrammarLocation(document, parser);
 
-				updateExternalGrammarLocation(document, parser);
-				parser.setFeature("http://apache.org/xml/features/validation/schema", hasSchemaGrammar); //$NON-NLS-1$
+			boolean hasSchemaLocation = document.hasSchemaLocation();
+			boolean hasNoNamespaceSchemaLocation = document.hasNoNamespaceSchemaLocation();
+			boolean hasSchemaGrammar = hasSchemaLocation || hasNoNamespaceSchemaLocation
+					|| hasExternalSchemaGrammar(document);
+			boolean schemaValidationEnabled = (hasSchemaGrammar
+					&& isSchemaValidationEnabled(document, validationSettings)
+					|| (hasNoNamespaceSchemaLocation
+							&& isNoNamespaceSchemaValidationEnabled(document, validationSettings)));
+			parser.setFeature("http://apache.org/xml/features/validation/schema", schemaValidationEnabled); //$NON-NLS-1$
 
-				// warn if XML document is not bound to a grammar according the settings
-				warnNoGrammar(document, diagnostics, validationSettings);
-			} else {
-				hasGrammar = false; // validation for Schema was disabled
+			boolean hasGrammar = document.hasDTD() || hasSchemaGrammar || document.hasExternalGrammar();
+			if (hasSchemaGrammar && !schemaValidationEnabled) {
+				hasGrammar = false;
 			}
 			parser.setFeature("http://xml.org/sax/features/validation", hasGrammar); //$NON-NLS-1$
 
@@ -114,6 +127,125 @@ public static void doDiagnostics(DOMDocument document, XMLEntityResolver entityR
 		}
 	}
 
+	private static boolean isSchemaValidationEnabled(DOMDocument document, XMLValidationSettings validationSettings) {
+		if (validationSettings == null) {
+			return true;
+		}
+		SchemaEnabled enabled = SchemaEnabled.always;
+		XMLSchemaSettings schemaSettings = validationSettings.getSchema();
+		if (schemaSettings != null && schemaSettings.getEnabled() != null) {
+			enabled = schemaSettings.getEnabled();
+		}
+		switch (enabled) {
+		case always:
+			return true;
+		case never:
+			return false;
+		case onValidSchema:
+			return isValidSchemaLocation(document);
+		default:
+			return true;
+		}
+	}
+
+	/**
+	 * Returns true if the given DOM document declares a xsi:schemaLocation hint for
+	 * the document root element is valid and false otherwise.
+	 * 
+	 * The xsi:schemaLocation is valid if:
+	 * 
+	 * <ul>
+	 * <li>xsi:schemaLocation defines an URI for the namespace of the document
+	 * element.</li>
+	 * <li>the URI can be opened</li>
+	 * </ul>
+	 * 
+	 * @param document the DOM document.
+	 * @return true if the given DOM document declares a xsi:schemaLocation hint for
+	 *         the document root element is valid and false otherwise.
+	 */
+	private static boolean isValidSchemaLocation(DOMDocument document) {
+		if (!document.hasSchemaLocation()) {
+			return false;
+		}
+		String namespaceURI = document.getNamespaceURI();
+		SchemaLocationHint hint = document.getSchemaLocation().getLocationHint(namespaceURI);
+		if (hint == null) {
+			return false;
+		}
+		String location = hint.getHint();
+		return isValidLocation(document.getDocumentURI(), location);
+	}
+
+	private static boolean isNoNamespaceSchemaValidationEnabled(DOMDocument document,
+			XMLValidationSettings validationSettings) {
+		if (validationSettings == null) {
+			return true;
+		}
+		SchemaEnabled enabled = SchemaEnabled.always;
+		XMLSchemaSettings schemaSettings = validationSettings.getSchema();
+		if (schemaSettings != null && schemaSettings.getEnabled() != null) {
+			enabled = schemaSettings.getEnabled();
+		}
+		switch (enabled) {
+		case always:
+			return true;
+		case never:
+			return false;
+		case onValidSchema:
+			return isValidNoNamespaceSchemaLocation(document);
+		default:
+			return true;
+		}
+	}
+
+	/**
+	 * Returns true if the given DOM document declares a
+	 * xsi:noNamespaceSchemaLocation which is valid and false otherwise.
+	 * 
+	 * The xsi:noNamespaceSchemaLocation is valid if:
+	 * 
+	 * <ul>
+	 * <li>xsi:noNamespaceSchemaLocation defines an URI.</li>
+	 * <li>the URI can be opened</li>
+	 * </ul>
+	 * 
+	 * @param document the DOM document.
+	 * @return true if the given DOM document declares a xsi:schemaLocation hint for
+	 *         the document root element is valid and false otherwise.
+	 */
+	private static boolean isValidNoNamespaceSchemaLocation(DOMDocument document) {
+		NoNamespaceSchemaLocation noNamespaceSchemaLocation = document.getNoNamespaceSchemaLocation();
+		if (noNamespaceSchemaLocation == null) {
+			return false;
+		}
+		String location = noNamespaceSchemaLocation.getLocation();
+		return isValidLocation(document.getDocumentURI(), location);
+	}
+
+	private static boolean isValidLocation(String documentURI, String location) {
+		String resolvedLocation = getResolvedLocation(documentURI, location);
+		if (resolvedLocation == null) {
+			return false;
+		}
+		try (InputStream is = new URL(resolvedLocation).openStream()) {
+			return true;
+		} catch (Exception e) {
+			return false;
+		}
+	}
+
+	private static String getResolvedLocation(String documentURI, String location) {
+		if (StringUtils.isBlank(location)) {
+			return null;
+		}
+		try {
+			return XMLEntityManager.expandSystemId(location, documentURI, false);
+		} catch (MalformedURIException e) {
+			return location;
+		}
+	}
+
 	private static boolean hasExternalSchemaGrammar(DOMDocument document) {
 		if (document.getExternalGrammarFromNamespaceURI() != null) {
 			return true;

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/settings/SchemaEnabled.java

@@ -0,0 +1,17 @@
+/**
+ *  Copyright (c) 2021 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
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ *  Contributors:
+ *  Red Hat Inc. - initial API and implementation
+ */
+package org.eclipse.lemminx.extensions.contentmodel.settings;
+
+public enum SchemaEnabled {
+	always, never, onValidSchema;
+}

org.eclipse.lemminx/src/main/java/org/eclipse/lemminx/extensions/contentmodel/settings/XMLSchemaSettings.java

@@ -0,0 +1,56 @@
+/**
+ *  Copyright (c) 2021 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
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ *  Contributors:
+ *  Red Hat Inc. - initial API and implementation
+ */
+package org.eclipse.lemminx.extensions.contentmodel.settings;
+
+/**
+ * XML Schema settings.
+ *
+ */
+public class XMLSchemaSettings {
+
+	public XMLSchemaSettings() {
+		setEnabled(SchemaEnabled.always);
+	}
+
+	private SchemaEnabled enabled;
+
+	public void setEnabled(SchemaEnabled enabled) {
+		this.enabled = enabled;
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((enabled == null) ? 0 : enabled.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		XMLSchemaSettings other = (XMLSchemaSettings) obj;
+		if (enabled != other.enabled)
+			return false;
+		return true;
+	}
+
+	public SchemaEnabled getEnabled() {
+		return enabled;
+	}
+}