restconf/restconf-nb-rfc8040/src/main/java/org/opendaylight/restconf/nb/rfc8040/streams/listeners/AbstractNotificationsData.java

   1 /*
   2  * Copyright (c) 2016 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.restconf.nb.rfc8040.streams.listeners;
   9
  10 import java.io.ByteArrayOutputStream;
  11 import java.io.IOException;
  12 import java.nio.charset.StandardCharsets;
  13 import java.time.Instant;
  14 import java.time.OffsetDateTime;
  15 import java.time.ZoneId;
  16 import java.time.format.DateTimeFormatter;
  17 import javax.xml.stream.XMLOutputFactory;
  18 import javax.xml.stream.XMLStreamException;
  19 import javax.xml.stream.XMLStreamWriter;
  20 import javax.xml.transform.OutputKeys;
  21 import javax.xml.transform.Transformer;
  22 import javax.xml.transform.TransformerException;
  23 import javax.xml.transform.TransformerFactory;
  24 import javax.xml.transform.dom.DOMResult;
  25 import javax.xml.transform.dom.DOMSource;
  26 import javax.xml.transform.stream.StreamResult;
  27 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  28 import org.opendaylight.mdsal.dom.api.DOMDataTreeWriteTransaction;
  29 import org.opendaylight.mdsal.dom.api.DOMTransactionChain;
  30 import org.opendaylight.restconf.nb.rfc8040.Rfc8040.MonitoringModule;
  31 import org.opendaylight.restconf.nb.rfc8040.handlers.SchemaContextHandler;
  32 import org.opendaylight.restconf.nb.rfc8040.handlers.TransactionChainHandler;
  33 import org.opendaylight.restconf.nb.rfc8040.utils.parser.IdentifierCodec;
  34 import org.opendaylight.yangtools.util.xml.UntrustedXML;
  35 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  36 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  37 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  38 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeWriter;
  39 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  40 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  41 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  42 import org.slf4j.Logger;
  43 import org.slf4j.LoggerFactory;
  44 import org.w3c.dom.Document;
  45 import org.w3c.dom.Element;
  46
  47 /**
  48  * Abstract class for processing and preparing data.
  49  *
  50  */
  51 abstract class AbstractNotificationsData {
  52     private static final Logger LOG = LoggerFactory.getLogger(AbstractNotificationsData.class);
  53     private static final TransformerFactory TF = TransformerFactory.newInstance();
  54     private static final XMLOutputFactory OF = XMLOutputFactory.newInstance();
  55
  56     private TransactionChainHandler transactionChainHandler;
  57     protected SchemaContextHandler schemaHandler;
  58     private String localName;
  59
  60     /**
  61      * Transaction chain for delete data in DS on close().
  62      *
  63      * @param transactionChainHandler
  64      *            creating new write transaction for delete data on close
  65      * @param schemaHandler
  66      *            for getting schema to deserialize
  67      *            {@link MonitoringModule#PATH_TO_STREAM_WITHOUT_KEY} to
  68      *            {@link YangInstanceIdentifier}
  69      */
  70     @SuppressWarnings("checkstyle:hiddenField")
  71     public void setCloseVars(final TransactionChainHandler transactionChainHandler,
  72             final SchemaContextHandler schemaHandler) {
  73         this.transactionChainHandler = transactionChainHandler;
  74         this.schemaHandler = schemaHandler;
  75     }
  76
  77     /**
  78      * Delete data in DS.
  79      */
  80     protected void deleteDataInDS() throws Exception {
  81         final DOMTransactionChain transactionChain = this.transactionChainHandler.get();
  82         final DOMDataTreeWriteTransaction wTx = transactionChain.newWriteOnlyTransaction();
  83         wTx.delete(LogicalDatastoreType.OPERATIONAL, IdentifierCodec
  84                 .deserialize(MonitoringModule.PATH_TO_STREAM_WITHOUT_KEY + this.localName, this.schemaHandler.get()));
  85         wTx.commit().get();
  86         transactionChain.close();
  87     }
  88
  89     /**
  90      * Set localName of last path element of specific listener.
  91      *
  92      * @param localName
  93      *            local name
  94      */
  95     @SuppressWarnings("checkstyle:hiddenField")
  96     protected void setLocalNameOfPath(final String localName) {
  97         this.localName = localName;
  98     }
  99
 100     /**
 101      * Formats data specified by RFC3339.
 102      *
 103      * @param now time stamp
 104      * @return Data specified by RFC3339.
 105      */
 106     protected static String toRFC3339(final Instant now) {
 107         return DateTimeFormatter.ISO_OFFSET_DATE_TIME.format(OffsetDateTime.ofInstant(now, ZoneId.systemDefault()));
 108     }
 109
 110     /**
 111      * Creates {@link Document} document.
 112      *
 113      * @return {@link Document} document.
 114      */
 115     protected static Document createDocument() {
 116         return UntrustedXML.newDocumentBuilder().newDocument();
 117     }
 118
 119     /**
 120      * Write normalized node to {@link DOMResult}.
 121      *
 122      * @param normalized
 123      *            data
 124      * @param context
 125      *            actual schema context
 126      * @param schemaPath
 127      *            schema path of data
 128      * @return {@link DOMResult}
 129      */
 130     protected DOMResult writeNormalizedNode(final NormalizedNode<?, ?> normalized, final SchemaContext context,
 131             final SchemaPath schemaPath) throws IOException, XMLStreamException {
 132         final Document doc = UntrustedXML.newDocumentBuilder().newDocument();
 133         final DOMResult result = new DOMResult(doc);
 134         NormalizedNodeWriter normalizedNodeWriter = null;
 135         NormalizedNodeStreamWriter normalizedNodeStreamWriter = null;
 136         XMLStreamWriter writer = null;
 137
 138         try {
 139             writer = OF.createXMLStreamWriter(result);
 140             normalizedNodeStreamWriter = XMLStreamNormalizedNodeStreamWriter.create(writer, context, schemaPath);
 141             normalizedNodeWriter = NormalizedNodeWriter.forStreamWriter(normalizedNodeStreamWriter);
 142
 143             normalizedNodeWriter.write(normalized);
 144
 145             normalizedNodeWriter.flush();
 146         } finally {
 147             if (normalizedNodeWriter != null) {
 148                 normalizedNodeWriter.close();
 149             }
 150             if (normalizedNodeStreamWriter != null) {
 151                 normalizedNodeStreamWriter.close();
 152             }
 153             if (writer != null) {
 154                 writer.close();
 155             }
 156         }
 157
 158         return result;
 159     }
 160
 161     /**
 162      * Generating base element of every notification.
 163      *
 164      * @param doc
 165      *            base {@link Document}
 166      * @return element of {@link Document}
 167      */
 168     protected Element basePartDoc(final Document doc) {
 169         final Element notificationElement =
 170                 doc.createElementNS("urn:ietf:params:xml:ns:netconf:notification:1.0", "notification");
 171
 172         doc.appendChild(notificationElement);
 173
 174         final Element eventTimeElement = doc.createElement("eventTime");
 175         eventTimeElement.setTextContent(toRFC3339(Instant.now()));
 176         notificationElement.appendChild(eventTimeElement);
 177
 178         return notificationElement;
 179     }
 180
 181     /**
 182      * Generating of {@link Document} transforming to string.
 183      *
 184      * @param doc
 185      *            {@link Document} with data
 186      * @return - string from {@link Document}
 187      */
 188     protected String transformDoc(final Document doc) {
 189         final ByteArrayOutputStream out = new ByteArrayOutputStream();
 190
 191         try {
 192             final Transformer transformer = TF.newTransformer();
 193             transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "no");
 194             transformer.setOutputProperty(OutputKeys.METHOD, "xml");
 195             transformer.setOutputProperty(OutputKeys.INDENT, "yes");
 196             transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8");
 197             transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
 198             transformer.transform(new DOMSource(doc), new StreamResult(out));
 199         } catch (final TransformerException e) {
 200             // FIXME: this should raise an exception
 201             final String msg = "Error during transformation of Document into String";
 202             LOG.error(msg, e);
 203             return msg;
 204         }
 205
 206         return new String(out.toByteArray(), StandardCharsets.UTF_8);
 207     }
 208 }