restconf/sal-rest-connector/src/main/java/org/opendaylight/netconf/sal/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.netconf.sal.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.controller.md.sal.common.api.data.LogicalDatastoreType;
  28 import org.opendaylight.controller.md.sal.dom.api.DOMDataWriteTransaction;
  29 import org.opendaylight.restconf.Rfc8040.MonitoringModule;
  30 import org.opendaylight.restconf.handlers.SchemaContextHandler;
  31 import org.opendaylight.restconf.handlers.TransactionChainHandler;
  32 import org.opendaylight.restconf.parser.IdentifierCodec;
  33 import org.opendaylight.yangtools.util.xml.UntrustedXML;
  34 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  35 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  36 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  37 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeWriter;
  38 import org.opendaylight.yangtools.yang.data.impl.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  39 import org.opendaylight.yangtools.yang.data.impl.codec.xml.XmlDocumentUtils;
  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
  55     private TransactionChainHandler transactionChainHandler;
  56     private SchemaContextHandler schemaHandler;
  57     private String localName;
  58
  59     /**
  60      * Transaction chain for delete data in DS on close().
  61      *
  62      * @param transactionChainHandler
  63      *            creating new write transaction for delete data on close
  64      * @param schemaHandler
  65      *            for getting schema to deserialize
  66      *            {@link MonitoringModule#PATH_TO_STREAM_WITHOUT_KEY} to
  67      *            {@link YangInstanceIdentifier}
  68      */
  69     public void setCloseVars(final TransactionChainHandler transactionChainHandler,
  70             final SchemaContextHandler schemaHandler) {
  71         this.transactionChainHandler = transactionChainHandler;
  72         this.schemaHandler = schemaHandler;
  73     }
  74
  75     /**
  76      * Delete data in DS.
  77      */
  78     protected void deleteDataInDS() throws Exception {
  79         final DOMDataWriteTransaction wTx = this.transactionChainHandler.get().newWriteOnlyTransaction();
  80         wTx.delete(LogicalDatastoreType.OPERATIONAL, IdentifierCodec
  81                 .deserialize(MonitoringModule.PATH_TO_STREAM_WITHOUT_KEY + this.localName, this.schemaHandler.get()));
  82         wTx.submit().checkedGet();
  83     }
  84
  85     /**
  86      * Set localName of last path element of specific listener.
  87      *
  88      * @param localName
  89      *            local name
  90      */
  91     protected void setLocalNameOfPath(final String localName) {
  92         this.localName = localName;
  93     }
  94
  95     /**
  96      * Formats data specified by RFC3339.
  97      *
  98      * @param now time stamp
  99      * @return Data specified by RFC3339.
 100      */
 101     protected static String toRFC3339(final Instant now) {
 102         return DateTimeFormatter.ISO_OFFSET_DATE_TIME.format(OffsetDateTime.ofInstant(now, ZoneId.systemDefault()));
 103     }
 104
 105     /**
 106      * Creates {@link Document} document.
 107      *
 108      * @return {@link Document} document.
 109      */
 110     protected static Document createDocument() {
 111         return UntrustedXML.newDocumentBuilder().newDocument();
 112     }
 113
 114     /**
 115      * Write normalized node to {@link DOMResult}.
 116      *
 117      * @param normalized
 118      *            data
 119      * @param context
 120      *            actual schema context
 121      * @param schemaPath
 122      *            schema path of data
 123      * @return {@link DOMResult}
 124      */
 125     protected DOMResult writeNormalizedNode(final NormalizedNode<?, ?> normalized, final SchemaContext context,
 126             final SchemaPath schemaPath) throws IOException, XMLStreamException {
 127         final XMLOutputFactory xmlFactory = XMLOutputFactory.newFactory();
 128         final Document doc = XmlDocumentUtils.getDocument();
 129         final DOMResult result = new DOMResult(doc);
 130         NormalizedNodeWriter normalizedNodeWriter = null;
 131         NormalizedNodeStreamWriter normalizedNodeStreamWriter = null;
 132         XMLStreamWriter writer = null;
 133
 134         try {
 135             writer = xmlFactory.createXMLStreamWriter(result);
 136             normalizedNodeStreamWriter = XMLStreamNormalizedNodeStreamWriter.create(writer, context, schemaPath);
 137             normalizedNodeWriter = NormalizedNodeWriter.forStreamWriter(normalizedNodeStreamWriter);
 138
 139             normalizedNodeWriter.write(normalized);
 140
 141             normalizedNodeWriter.flush();
 142         } finally {
 143             if (normalizedNodeWriter != null) {
 144                 normalizedNodeWriter.close();
 145             }
 146             if (normalizedNodeStreamWriter != null) {
 147                 normalizedNodeStreamWriter.close();
 148             }
 149             if (writer != null) {
 150                 writer.close();
 151             }
 152         }
 153
 154         return result;
 155     }
 156
 157     /**
 158      * Generating base element of every notification.
 159      *
 160      * @param doc
 161      *            base {@link Document}
 162      * @return element of {@link Document}
 163      */
 164     protected Element basePartDoc(final Document doc) {
 165         final Element notificationElement =
 166                 doc.createElementNS("urn:ietf:params:xml:ns:netconf:notification:1.0", "notification");
 167
 168         doc.appendChild(notificationElement);
 169
 170         final Element eventTimeElement = doc.createElement("eventTime");
 171         eventTimeElement.setTextContent(toRFC3339(Instant.now()));
 172         notificationElement.appendChild(eventTimeElement);
 173
 174         return notificationElement;
 175     }
 176
 177     /**
 178      * Generating of {@link Document} transforming to string.
 179      *
 180      * @param doc
 181      *            {@link Document} with data
 182      * @return - string from {@link Document}
 183      */
 184     protected String transformDoc(final Document doc) {
 185         final ByteArrayOutputStream out = new ByteArrayOutputStream();
 186
 187         try {
 188             final Transformer transformer = TF.newTransformer();
 189             transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "no");
 190             transformer.setOutputProperty(OutputKeys.METHOD, "xml");
 191             transformer.setOutputProperty(OutputKeys.INDENT, "yes");
 192             transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8");
 193             transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
 194             transformer.transform(new DOMSource(doc), new StreamResult(out));
 195         } catch (TransformerException e) {
 196             // FIXME: this should raise an exception
 197             final String msg = "Error during transformation of Document into String";
 198             LOG.error(msg, e);
 199             return msg;
 200         }
 201
 202         return new String(out.toByteArray(), StandardCharsets.UTF_8);
 203     }
 204 }