bgp/config-loader-impl/src/main/java/org/opendaylight/protocol/bgp/config/loader/impl/ConfigLoaderImpl.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
   9 package org.opendaylight.protocol.bgp.config.loader.impl;
  10
  11 import static java.util.Objects.requireNonNull;
  12
  13 import java.io.File;
  14 import java.io.FileInputStream;
  15 import java.io.IOException;
  16 import java.io.InputStream;
  17 import java.net.URISyntaxException;
  18 import java.nio.file.WatchEvent;
  19 import java.nio.file.WatchKey;
  20 import java.nio.file.WatchService;
  21 import java.util.HashMap;
  22 import java.util.Map;
  23 import java.util.regex.Pattern;
  24 import javax.annotation.concurrent.GuardedBy;
  25 import javax.xml.parsers.ParserConfigurationException;
  26 import javax.xml.stream.XMLInputFactory;
  27 import javax.xml.stream.XMLStreamException;
  28 import javax.xml.stream.XMLStreamReader;
  29 import org.opendaylight.mdsal.binding.dom.codec.api.BindingNormalizedNodeSerializer;
  30 import org.opendaylight.protocol.bgp.config.loader.spi.ConfigFileProcessor;
  31 import org.opendaylight.protocol.bgp.config.loader.spi.ConfigLoader;
  32 import org.opendaylight.yangtools.concepts.AbstractRegistration;
  33 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  34 import org.opendaylight.yangtools.yang.data.api.schema.stream.NormalizedNodeStreamWriter;
  35 import org.opendaylight.yangtools.yang.data.codec.xml.XmlParserStream;
  36 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNormalizedNodeStreamWriter;
  37 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeResult;
  38 import org.opendaylight.yangtools.yang.model.api.SchemaContext;
  39 import org.opendaylight.yangtools.yang.model.api.SchemaNode;
  40 import org.opendaylight.yangtools.yang.model.util.SchemaContextUtil;
  41 import org.slf4j.Logger;
  42 import org.slf4j.LoggerFactory;
  43 import org.xml.sax.SAXException;
  44
  45 public final class ConfigLoaderImpl implements ConfigLoader, AutoCloseable {
  46     private static final Logger LOG = LoggerFactory.getLogger(ConfigLoaderImpl.class);
  47     private static final String INTERRUPTED = "InterruptedException";
  48     private static final String EXTENSION = "-.*\\.xml";
  49     private static final String INITIAL = "^";
  50     @GuardedBy("this")
  51     private final Map<String, ConfigFileProcessor> configServices = new HashMap<>();
  52     private final SchemaContext schemaContext;
  53     private final BindingNormalizedNodeSerializer bindingSerializer;
  54     private final String path;
  55     private final Thread watcherThread;
  56
  57     public ConfigLoaderImpl(final SchemaContext schemaContext, final BindingNormalizedNodeSerializer bindingSerializer,
  58         final String path, final WatchService watchService) {
  59         this.schemaContext = requireNonNull(schemaContext);
  60         this.bindingSerializer = requireNonNull(bindingSerializer);
  61         this.path = requireNonNull(path);
  62         requireNonNull(watchService);
  63         this.watcherThread = new Thread(new ConfigLoaderImplRunnable(watchService));
  64         this.watcherThread.start();
  65         LOG.info("Config Loader service initiated");
  66     }
  67
  68     private void handleConfigFile(final ConfigFileProcessor config, final String filename) {
  69         final NormalizedNode<?, ?> dto;
  70         try {
  71             dto = parseDefaultConfigFile(config, filename);
  72         } catch (final Exception e) {
  73             LOG.warn("Failed to parse config file {}", filename, e);
  74             return;
  75         }
  76         LOG.info("Loading initial config {}", filename);
  77         config.loadConfiguration(dto);
  78     }
  79
  80     private NormalizedNode<?, ?> parseDefaultConfigFile(final ConfigFileProcessor config, final String filename)
  81         throws IOException, XMLStreamException, ParserConfigurationException, SAXException, URISyntaxException {
  82         final NormalizedNodeResult result = new NormalizedNodeResult();
  83         final NormalizedNodeStreamWriter streamWriter = ImmutableNormalizedNodeStreamWriter.from(result);
  84
  85         final InputStream resourceAsStream = new FileInputStream(new File(this.path, filename));
  86         final XMLInputFactory factory = XMLInputFactory.newInstance();
  87         final XMLStreamReader reader = factory.createXMLStreamReader(resourceAsStream);
  88
  89         final SchemaNode schemaNode = SchemaContextUtil.findDataSchemaNode(this.schemaContext, config.getSchemaPath());
  90         final XmlParserStream xmlParser = XmlParserStream.create(streamWriter, this.schemaContext, schemaNode);
  91         xmlParser.parse(reader);
  92
  93         return result.getResult();
  94     }
  95
  96     @Override
  97     public synchronized AbstractRegistration registerConfigFile(final ConfigFileProcessor config) {
  98         final String pattern = INITIAL + config.getSchemaPath().getLastComponent().getLocalName() + EXTENSION;
  99         this.configServices.put(pattern, config);
 100
 101         final File[] fList = new File(this.path).listFiles();
 102         if (fList != null) {
 103             for (final File file : fList) {
 104                 if (file.isFile()) {
 105                     final String filename = file.getName();
 106                     if (Pattern.matches(pattern, filename)) {
 107                         handleConfigFile(config, filename);
 108                     }
 109                 }
 110             }
 111         }
 112
 113         return new AbstractRegistration() {
 114             @Override
 115             protected void removeRegistration() {
 116                 synchronized (ConfigLoaderImpl.this) {
 117                     ConfigLoaderImpl.this.configServices.remove(pattern);
 118                 }
 119             }
 120         };
 121     }
 122
 123     @Override
 124     public BindingNormalizedNodeSerializer getBindingNormalizedNodeSerializer() {
 125         return this.bindingSerializer;
 126     }
 127
 128
 129     @Override
 130     public void close() throws Exception {
 131         this.watcherThread.interrupt();
 132     }
 133
 134     private class ConfigLoaderImplRunnable implements Runnable {
 135         private final WatchService watchService;
 136
 137         ConfigLoaderImplRunnable(final WatchService watchService) {
 138             this.watchService = watchService;
 139         }
 140
 141         @Override
 142         public void run() {
 143             try {
 144                 while (!Thread.currentThread().isInterrupted()) {
 145                     handleChanges(this.watchService);
 146                 }
 147             } catch (final Exception e) {
 148                 LOG.warn(INTERRUPTED, e);
 149             }
 150         }
 151
 152         private synchronized void handleChanges(final WatchService watchService) {
 153             try {
 154                 final WatchKey key = watchService.take();
 155                 if (key != null) {
 156                     for (final WatchEvent<?> event : key.pollEvents()) {
 157                         handleEvent(event.context().toString());
 158                     }
 159                     final boolean reset = key.reset();
 160                     if (!reset) {
 161                         LOG.warn("Could not reset the watch key.");
 162                     }
 163                 }
 164             } catch (final InterruptedException e) {
 165                 LOG.warn(INTERRUPTED, e);
 166             }
 167         }
 168
 169         private synchronized void handleEvent(final String filename) {
 170             ConfigLoaderImpl.this.configServices.entrySet().stream()
 171                 .filter(entry -> Pattern.matches(entry.getKey(), filename)).
 172                 forEach(entry -> handleConfigFile(entry.getValue(), filename));
 173         }
 174     }
 175 }