Java tutorial
/* * Copyright (c) 2016 Brocade Communications Systems, Inc. and others. All rights reserved. * * This program and the accompanying materials are made available under the * terms of the Eclipse Public License v1.0 which accompanies this distribution, * and is available at http://www.eclipse.org/legal/epl-v10.html */ package org.opendaylight.controller.blueprint.ext; import com.google.common.base.Optional; import com.google.common.base.Strings; import com.google.common.io.Resources; import java.io.IOException; import java.io.InputStream; import java.net.URISyntaxException; import java.net.URL; import javax.xml.parsers.ParserConfigurationException; import javax.xml.stream.XMLStreamException; import org.opendaylight.mdsal.binding.dom.codec.api.BindingNormalizedNodeSerializer; import org.opendaylight.mdsal.dom.api.DOMSchemaService; import org.opendaylight.yangtools.util.xml.UntrustedXML; import org.opendaylight.yangtools.yang.binding.DataObject; import org.opendaylight.yangtools.yang.common.QName; import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier; import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode; import org.opendaylight.yangtools.yang.model.api.DataSchemaNode; import org.opendaylight.yangtools.yang.model.api.Module; import org.opendaylight.yangtools.yang.model.api.SchemaContext; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.w3c.dom.Document; import org.xml.sax.SAXException; /** * DataObject XML file reader used by {@link DataStoreAppConfigMetadata}. * Available as a standalone class to make it easy to write unit tests which can * catch malformed default "clustered-app-conf" config data XML files in * downstream projects. * * @author Thomas Pantelis (originally; re-factored by Michael Vorburger.ch) */ public class DataStoreAppConfigDefaultXMLReader<T extends DataObject> { private static final Logger LOG = LoggerFactory.getLogger(DataStoreAppConfigDefaultXMLReader.class); private final String logName; private final String defaultAppConfigFileName; private final DOMSchemaService schemaService; private final BindingNormalizedNodeSerializer bindingSerializer; private final BindingContext bindingContext; private final ConfigURLProvider inputStreamProvider; @FunctionalInterface public interface FallbackConfigProvider { NormalizedNode<?, ?> get(SchemaContext schemaContext, DataSchemaNode dataSchema) throws IOException, XMLStreamException, ParserConfigurationException, SAXException, URISyntaxException; } @FunctionalInterface public interface ConfigURLProvider { Optional<URL> getURL(String appConfigFileName) throws IOException; } public DataStoreAppConfigDefaultXMLReader(final String logName, final String defaultAppConfigFileName, final DOMSchemaService schemaService, final BindingNormalizedNodeSerializer bindingSerializer, final BindingContext bindingContext, final ConfigURLProvider inputStreamProvider) { this.logName = logName; this.defaultAppConfigFileName = defaultAppConfigFileName; this.schemaService = schemaService; this.bindingSerializer = bindingSerializer; this.bindingContext = bindingContext; this.inputStreamProvider = inputStreamProvider; } public DataStoreAppConfigDefaultXMLReader(final Class<?> testClass, final String defaultAppConfigFileName, final DOMSchemaService schemaService, final BindingNormalizedNodeSerializer bindingSerializer, final Class<T> klass) { this(testClass.getName(), defaultAppConfigFileName, schemaService, bindingSerializer, BindingContext.create(testClass.getName(), klass, null), appConfigFileName -> Optional.of(getURL(testClass, defaultAppConfigFileName))); } private static URL getURL(final Class<?> testClass, final String defaultAppConfigFileName) { return Resources.getResource(testClass, defaultAppConfigFileName); } public T createDefaultInstance() throws ConfigXMLReaderException, ParserConfigurationException, XMLStreamException, IOException, SAXException, URISyntaxException { return createDefaultInstance((schemaContext, dataSchema) -> { throw new IllegalArgumentException("Failed to read XML " + "(not creating model from defaults as runtime would, for better clarity in tests)"); }); } @SuppressWarnings("unchecked") public T createDefaultInstance(final FallbackConfigProvider fallback) throws ConfigXMLReaderException, URISyntaxException, ParserConfigurationException, XMLStreamException, SAXException, IOException { YangInstanceIdentifier yangPath = bindingSerializer.toYangInstanceIdentifier(bindingContext.appConfigPath); LOG.debug("{}: Creating app config instance from path {}, Qname: {}", logName, yangPath, bindingContext.bindingQName); checkNotNull(schemaService, "%s: Could not obtain the SchemaService OSGi service", logName); SchemaContext schemaContext = schemaService.getGlobalContext(); Module module = schemaContext.findModule(bindingContext.bindingQName.getModule()).orElse(null); checkNotNull(module, "%s: Could not obtain the module schema for namespace %s, revision %s", logName, bindingContext.bindingQName.getNamespace(), bindingContext.bindingQName.getRevision()); DataSchemaNode dataSchema = module.getDataChildByName(bindingContext.bindingQName); checkNotNull(dataSchema, "%s: Could not obtain the schema for %s", logName, bindingContext.bindingQName); checkCondition(bindingContext.schemaType.isAssignableFrom(dataSchema.getClass()), "%s: Expected schema type %s for %s but actual type is %s", logName, bindingContext.schemaType, bindingContext.bindingQName, dataSchema.getClass()); NormalizedNode<?, ?> dataNode = parsePossibleDefaultAppConfigXMLFile(schemaContext, dataSchema); if (dataNode == null) { dataNode = fallback.get(schemaService.getGlobalContext(), dataSchema); } DataObject appConfig = bindingSerializer.fromNormalizedNode(yangPath, dataNode).getValue(); // This shouldn't happen but need to handle it in case... checkNotNull(appConfig, "%s: Could not create instance for app config binding %s", logName, bindingContext.appConfigBindingClass); return (T) appConfig; } private static void checkNotNull(final Object reference, final String errorMessageFormat, final Object... formatArgs) throws ConfigXMLReaderException { checkCondition(reference != null, errorMessageFormat, formatArgs); } private static void checkCondition(final boolean expression, final String errorMessageFormat, final Object... formatArgs) throws ConfigXMLReaderException { if (!expression) { throw new ConfigXMLReaderException(String.format(errorMessageFormat, formatArgs)); } } private NormalizedNode<?, ?> parsePossibleDefaultAppConfigXMLFile(final SchemaContext schemaContext, final DataSchemaNode dataSchema) throws ConfigXMLReaderException { String appConfigFileName = defaultAppConfigFileName; if (Strings.isNullOrEmpty(appConfigFileName)) { String moduleName = findYangModuleName(bindingContext.bindingQName, schemaContext); appConfigFileName = moduleName + "_" + bindingContext.bindingQName.getLocalName() + ".xml"; } Optional<URL> optionalURL; try { optionalURL = inputStreamProvider.getURL(appConfigFileName); } catch (final IOException e) { String msg = String.format("%s: Could not getURL()", logName); LOG.error(msg, e); throw new ConfigXMLReaderException(msg, e); } if (!optionalURL.isPresent()) { return null; } URL url = optionalURL.get(); try (InputStream is = url.openStream()) { Document root = UntrustedXML.newDocumentBuilder().parse(is); NormalizedNode<?, ?> dataNode = bindingContext.parseDataElement(root.getDocumentElement(), dataSchema, schemaContext); LOG.debug("{}: Parsed data node: {}", logName, dataNode); return dataNode; } catch (final IOException | SAXException | XMLStreamException | ParserConfigurationException | URISyntaxException e) { String msg = String.format("%s: Could not read/parse app config %s", logName, url); LOG.error(msg, e); throw new ConfigXMLReaderException(msg, e); } } private String findYangModuleName(final QName qname, final SchemaContext schemaContext) throws ConfigXMLReaderException { for (Module m : schemaContext.getModules()) { if (qname.getModule().equals(m.getQNameModule())) { return m.getName(); } } throw new ConfigXMLReaderException( String.format("%s: Could not find yang module for QName %s", logName, qname)); } }