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;
  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.schema.NormalizedNode;
  35 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  36 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeWriter;
  37 import org.opendaylight.yangtools.yang.data.codec.xml.XMLStreamNormalizedNodeStreamWriter;
  38 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  39 import org.opendaylight.yangtools.yang.model.api.SchemaPath;
  40 import org.slf4j.Logger;
  41 import org.slf4j.LoggerFactory;
  42 import org.w3c.dom.Document;
  43 import org.w3c.dom.Element;
  44
  45 /**
  46  * Abstract class for processing and preparing data.
  47  *
  48  */
  49 abstract class AbstractNotificationsData {
  50     private static final Logger LOG = LoggerFactory.getLogger(AbstractNotificationsData.class);
  51     private static final TransformerFactory TF = TransformerFactory.newInstance();
  52     private static final XMLOutputFactory OF = XMLOutputFactory.newInstance();
  53
  54     private TransactionChainHandler transactionChainHandler;
  55     protected SchemaContextHandler schemaHandler;
  56     private String localName;
  57
  58     /**
  59      * Transaction chain for delete data in DS on close().
  60      *
  61      * @param transactionChainHandler creating new write transaction for delete data on close
  62      * @param schemaHandler for formatting notifications
  63      */
  64     @SuppressWarnings("checkstyle:hiddenField")
  65     public void setCloseVars(final TransactionChainHandler transactionChainHandler,
  66             final SchemaContextHandler schemaHandler) {
  67         this.transactionChainHandler = transactionChainHandler;
  68         this.schemaHandler = schemaHandler;
  69     }
  70
  71     /**
  72      * Delete data in DS.
  73      */
  74     protected void deleteDataInDS() throws Exception {
  75         final DOMTransactionChain transactionChain = this.transactionChainHandler.get();
  76         final DOMDataTreeWriteTransaction wTx = transactionChain.newWriteOnlyTransaction();
  77         wTx.delete(LogicalDatastoreType.OPERATIONAL, Rfc8040.restconfStateStreamPath(this.localName));
  78         wTx.commit().get();
  79         transactionChain.close();
  80     }
  81
  82     /**
  83      * Set localName of last path element of specific listener.
  84      *
  85      * @param localName
  86      *            local name
  87      */
  88     @SuppressWarnings("checkstyle:hiddenField")
  89     protected void setLocalNameOfPath(final String localName) {
  90         this.localName = localName;
  91     }
  92
  93     /**
  94      * Formats data specified by RFC3339.
  95      *
  96      * @param now time stamp
  97      * @return Data specified by RFC3339.
  98      */
  99     protected static String toRFC3339(final Instant now) {
 100         return DateTimeFormatter.ISO_OFFSET_DATE_TIME.format(OffsetDateTime.ofInstant(now, ZoneId.systemDefault()));
 101     }
 102
 103     /**
 104      * Creates {@link Document} document.
 105      *
 106      * @return {@link Document} document.
 107      */
 108     protected static Document createDocument() {
 109         return UntrustedXML.newDocumentBuilder().newDocument();
 110     }
 111
 112     /**
 113      * Write normalized node to {@link DOMResult}.
 114      *
 115      * @param normalized
 116      *            data
 117      * @param context
 118      *            actual schema context
 119      * @param schemaPath
 120      *            schema path of data
 121      * @return {@link DOMResult}
 122      */
 123     protected DOMResult writeNormalizedNode(final NormalizedNode<?, ?> normalized, final EffectiveModelContext context,
 124             final SchemaPath schemaPath) throws IOException, XMLStreamException {
 125         final Document doc = UntrustedXML.newDocumentBuilder().newDocument();
 126         final DOMResult result = new DOMResult(doc);
 127         NormalizedNodeWriter normalizedNodeWriter = null;
 128         NormalizedNodeStreamWriter normalizedNodeStreamWriter = null;
 129         XMLStreamWriter writer = null;
 130
 131         try {
 132             writer = OF.createXMLStreamWriter(result);
 133             normalizedNodeStreamWriter = XMLStreamNormalizedNodeStreamWriter.create(writer, context, schemaPath);
 134             normalizedNodeWriter = NormalizedNodeWriter.forStreamWriter(normalizedNodeStreamWriter);
 135
 136             normalizedNodeWriter.write(normalized);
 137
 138             normalizedNodeWriter.flush();
 139         } finally {
 140             if (normalizedNodeWriter != null) {
 141                 normalizedNodeWriter.close();
 142             }
 143             if (normalizedNodeStreamWriter != null) {
 144                 normalizedNodeStreamWriter.close();
 145             }
 146             if (writer != null) {
 147                 writer.close();
 148             }
 149         }
 150
 151         return result;
 152     }
 153
 154     /**
 155      * Generating base element of every notification.
 156      *
 157      * @param doc
 158      *            base {@link Document}
 159      * @return element of {@link Document}
 160      */
 161     protected Element basePartDoc(final Document doc) {
 162         final Element notificationElement =
 163                 doc.createElementNS("urn:ietf:params:xml:ns:netconf:notification:1.0", "notification");
 164
 165         doc.appendChild(notificationElement);
 166
 167         final Element eventTimeElement = doc.createElement("eventTime");
 168         eventTimeElement.setTextContent(toRFC3339(Instant.now()));
 169         notificationElement.appendChild(eventTimeElement);
 170
 171         return notificationElement;
 172     }
 173
 174     /**
 175      * Generating of {@link Document} transforming to string.
 176      *
 177      * @param doc
 178      *            {@link Document} with data
 179      * @return - string from {@link Document}
 180      */
 181     protected String transformDoc(final Document doc) {
 182         final ByteArrayOutputStream out = new ByteArrayOutputStream();
 183
 184         try {
 185             final Transformer transformer = TF.newTransformer();
 186             transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "no");
 187             transformer.setOutputProperty(OutputKeys.METHOD, "xml");
 188             transformer.setOutputProperty(OutputKeys.INDENT, "yes");
 189             transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8");
 190             transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
 191             transformer.transform(new DOMSource(doc), new StreamResult(out));
 192         } catch (final TransformerException e) {
 193             // FIXME: this should raise an exception
 194             final String msg = "Error during transformation of Document into String";
 195             LOG.error(msg, e);
 196             return msg;
 197         }
 198
 199         return new String(out.toByteArray(), StandardCharsets.UTF_8);
 200     }
 201 }