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.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.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  39 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  40 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  41 import org.slf4j.Logger;
  42 import org.slf4j.LoggerFactory;
  43 import org.w3c.dom.Document;
  44 import org.w3c.dom.Element;
  45
  46 /**
  47  * Abstract class for processing and preparing data.
  48  *
  49  */
  50 abstract class AbstractNotificationsData {
  51     private static final Logger LOG = LoggerFactory.getLogger(AbstractNotificationsData.class);
  52     private static final TransformerFactory TF = TransformerFactory.newInstance();
  53     private static final XMLOutputFactory OF = XMLOutputFactory.newInstance();
  54
  55     private TransactionChainHandler transactionChainHandler;
  56     protected 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     @SuppressWarnings("checkstyle:hiddenField")
  70     public void setCloseVars(final TransactionChainHandler transactionChainHandler,
  71             final SchemaContextHandler schemaHandler) {
  72         this.transactionChainHandler = transactionChainHandler;
  73         this.schemaHandler = schemaHandler;
  74     }
  75
  76     /**
  77      * Delete data in DS.
  78      */
  79     protected void deleteDataInDS() throws Exception {
  80         try (DOMTransactionChain transactionChain = this.transactionChainHandler.get()) {
  81             final DOMDataTreeWriteTransaction wTx = transactionChain.newWriteOnlyTransaction();
  82             wTx.delete(LogicalDatastoreType.OPERATIONAL, MonitoringModule.restconfStateStreamPath(this.localName));
  83             wTx.commit().get();
  84         }
  85     }
  86
  87     /**
  88      * Set localName of last path element of specific listener.
  89      *
  90      * @param localName
  91      *            local name
  92      */
  93     @SuppressWarnings("checkstyle:hiddenField")
  94     protected void setLocalNameOfPath(final String localName) {
  95         this.localName = localName;
  96     }
  97
  98     /**
  99      * Formats data specified by RFC3339.
 100      *
 101      * @param now time stamp
 102      * @return Data specified by RFC3339.
 103      */
 104     protected static String toRFC3339(final Instant now) {
 105         return DateTimeFormatter.ISO_OFFSET_DATE_TIME.format(OffsetDateTime.ofInstant(now, ZoneId.systemDefault()));
 106     }
 107
 108     /**
 109      * Creates {@link Document} document.
 110      *
 111      * @return {@link Document} document.
 112      */
 113     protected static Document createDocument() {
 114         return UntrustedXML.newDocumentBuilder().newDocument();
 115     }
 116
 117     /**
 118      * Write normalized node to {@link DOMResult}.
 119      *
 120      * @param normalized
 121      *            data
 122      * @param context
 123      *            actual schema context
 124      * @param schemaPath
 125      *            schema path of data
 126      * @return {@link DOMResult}
 127      */
 128     protected DOMResult writeNormalizedNode(final NormalizedNode<?, ?> normalized, final EffectiveModelContext context,
 129             final SchemaPath schemaPath) throws IOException, XMLStreamException {
 130         final Document doc = UntrustedXML.newDocumentBuilder().newDocument();
 131         final DOMResult result = new DOMResult(doc);
 132         NormalizedNodeWriter normalizedNodeWriter = null;
 133         NormalizedNodeStreamWriter normalizedNodeStreamWriter = null;
 134         XMLStreamWriter writer = null;
 135
 136         try {
 137             writer = OF.createXMLStreamWriter(result);
 138             normalizedNodeStreamWriter = XMLStreamNormalizedNodeStreamWriter.create(writer, context, schemaPath);
 139             normalizedNodeWriter = NormalizedNodeWriter.forStreamWriter(normalizedNodeStreamWriter);
 140
 141             normalizedNodeWriter.write(normalized);
 142
 143             normalizedNodeWriter.flush();
 144         } finally {
 145             if (normalizedNodeWriter != null) {
 146                 normalizedNodeWriter.close();
 147             }
 148             if (normalizedNodeStreamWriter != null) {
 149                 normalizedNodeStreamWriter.close();
 150             }
 151             if (writer != null) {
 152                 writer.close();
 153             }
 154         }
 155
 156         return result;
 157     }
 158
 159     /**
 160      * Generating base element of every notification.
 161      *
 162      * @param doc
 163      *            base {@link Document}
 164      * @return element of {@link Document}
 165      */
 166     protected Element basePartDoc(final Document doc) {
 167         final Element notificationElement =
 168                 doc.createElementNS("urn:ietf:params:xml:ns:netconf:notification:1.0", "notification");
 169
 170         doc.appendChild(notificationElement);
 171
 172         final Element eventTimeElement = doc.createElement("eventTime");
 173         eventTimeElement.setTextContent(toRFC3339(Instant.now()));
 174         notificationElement.appendChild(eventTimeElement);
 175
 176         return notificationElement;
 177     }
 178
 179     /**
 180      * Generating of {@link Document} transforming to string.
 181      *
 182      * @param doc
 183      *            {@link Document} with data
 184      * @return - string from {@link Document}
 185      */
 186     protected String transformDoc(final Document doc) {
 187         final ByteArrayOutputStream out = new ByteArrayOutputStream();
 188
 189         try {
 190             final Transformer transformer = TF.newTransformer();
 191             transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "no");
 192             transformer.setOutputProperty(OutputKeys.METHOD, "xml");
 193             transformer.setOutputProperty(OutputKeys.INDENT, "yes");
 194             transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8");
 195             transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
 196             transformer.transform(new DOMSource(doc), new StreamResult(out));
 197         } catch (final TransformerException e) {
 198             // FIXME: this should raise an exception
 199             final String msg = "Error during transformation of Document into String";
 200             LOG.error(msg, e);
 201             return msg;
 202         }
 203
 204         return new String(out.toByteArray(), StandardCharsets.UTF_8);
 205     }
 206 }