restconf/restconf-nb-rfc8040/src/main/java/org/opendaylight/restconf/nb/rfc8040/rests/services/impl/SubscribeToStreamUtil.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.rests.services.impl;
   9
  10 import static com.google.common.base.Strings.isNullOrEmpty;
  11
  12 import java.net.URI;
  13 import java.util.HashMap;
  14 import java.util.Map;
  15 import java.util.concurrent.ExecutionException;
  16 import javax.ws.rs.core.UriBuilder;
  17 import javax.ws.rs.core.UriInfo;
  18 import org.eclipse.jdt.annotation.NonNull;
  19 import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
  20 import org.opendaylight.mdsal.dom.api.DOMDataBroker;
  21 import org.opendaylight.mdsal.dom.api.DOMDataTreeWriteOperations;
  22 import org.opendaylight.mdsal.dom.api.DOMDataTreeWriteTransaction;
  23 import org.opendaylight.restconf.common.errors.RestconfDocumentedException;
  24 import org.opendaylight.restconf.nb.rfc8040.NotificationQueryParams;
  25 import org.opendaylight.restconf.nb.rfc8040.Rfc8040;
  26 import org.opendaylight.restconf.nb.rfc8040.handlers.SchemaContextHandler;
  27 import org.opendaylight.restconf.nb.rfc8040.rests.services.impl.RestconfStreamsSubscriptionServiceImpl.HandlersHolder;
  28 import org.opendaylight.restconf.nb.rfc8040.rests.utils.RestconfStreamsConstants;
  29 import org.opendaylight.restconf.nb.rfc8040.streams.listeners.ListenerAdapter;
  30 import org.opendaylight.restconf.nb.rfc8040.streams.listeners.ListenersBroker;
  31 import org.opendaylight.restconf.nb.rfc8040.streams.listeners.NotificationListenerAdapter;
  32 import org.opendaylight.restconf.nb.rfc8040.utils.RestconfConstants;
  33 import org.opendaylight.restconf.nb.rfc8040.utils.mapping.RestconfMappingNodeUtil;
  34 import org.opendaylight.restconf.nb.rfc8040.utils.parser.IdentifierCodec;
  35 import org.opendaylight.yangtools.yang.common.ErrorTag;
  36 import org.opendaylight.yangtools.yang.common.ErrorType;
  37 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
  38 import org.opendaylight.yangtools.yang.model.api.EffectiveModelContext;
  39 import org.slf4j.Logger;
  40 import org.slf4j.LoggerFactory;
  41
  42 /**
  43  * Subscribe to stream util class.
  44  */
  45 abstract class SubscribeToStreamUtil {
  46     /**
  47      * Implementation of SubscribeToStreamUtil for Server-sent events.
  48      */
  49     private static final class ServerSentEvents extends SubscribeToStreamUtil {
  50         static final ServerSentEvents INSTANCE = new ServerSentEvents();
  51
  52         @Override
  53         public URI prepareUriByStreamName(final UriInfo uriInfo, final String streamName) {
  54             final UriBuilder uriBuilder = uriInfo.getBaseUriBuilder();
  55             return uriBuilder.replacePath(RestconfConstants.BASE_URI_PATTERN + '/'
  56                     + RestconfConstants.NOTIF + '/' + streamName).build();
  57         }
  58     }
  59
  60     /**
  61      * Implementation of SubscribeToStreamUtil for Web sockets.
  62      */
  63     private static final class WebSockets extends SubscribeToStreamUtil {
  64         static final WebSockets INSTANCE = new WebSockets();
  65
  66         @Override
  67         public URI prepareUriByStreamName(final UriInfo uriInfo, final String streamName) {
  68             final String scheme = uriInfo.getAbsolutePath().getScheme();
  69             final UriBuilder uriBuilder = uriInfo.getBaseUriBuilder();
  70             switch (scheme) {
  71                 case "https":
  72                     // Secured HTTP goes to Secured WebSockets
  73                     uriBuilder.scheme("wss");
  74                     break;
  75                 case "http":
  76                 default:
  77                     // Unsecured HTTP and others go to unsecured WebSockets
  78                     uriBuilder.scheme("ws");
  79             }
  80             return uriBuilder.replacePath(RestconfConstants.BASE_URI_PATTERN + '/' + streamName).build();
  81         }
  82     }
  83
  84
  85     private static final Logger LOG = LoggerFactory.getLogger(SubscribeToStreamUtil.class);
  86
  87     SubscribeToStreamUtil() {
  88         // Hidden on purpose
  89     }
  90
  91     static SubscribeToStreamUtil serverSentEvents() {
  92         return ServerSentEvents.INSTANCE;
  93     }
  94
  95     static SubscribeToStreamUtil webSockets() {
  96         return WebSockets.INSTANCE;
  97     }
  98
  99     /**
 100      * Prepare URL from base name and stream name.
 101      *
 102      * @param uriInfo base URL information
 103      * @param streamName name of stream for create
 104      * @return final URL
 105      */
 106     abstract @NonNull URI prepareUriByStreamName(UriInfo uriInfo, String streamName);
 107
 108     /**
 109      * Register listener by streamName in identifier to listen to yang notifications, and put or delete information
 110      * about listener to DS according to ietf-restconf-monitoring.
 111      *
 112      * @param identifier              Name of the stream.
 113      * @param uriInfo                 URI information.
 114      * @param notificationQueryParams Query parameters of notification.
 115      * @param handlersHolder          Holder of handlers for notifications.
 116      * @return Stream location for listening.
 117      */
 118     final @NonNull URI subscribeToYangStream(final String identifier, final UriInfo uriInfo,
 119             final NotificationQueryParams notificationQueryParams, final HandlersHolder handlersHolder) {
 120         final String streamName = ListenersBroker.createStreamNameFromUri(identifier);
 121         if (isNullOrEmpty(streamName)) {
 122             throw new RestconfDocumentedException("Stream name is empty.", ErrorType.PROTOCOL, ErrorTag.INVALID_VALUE);
 123         }
 124
 125         final NotificationListenerAdapter notificationListenerAdapter = ListenersBroker.getInstance()
 126             .getNotificationListenerFor(streamName)
 127             .orElseThrow(() -> new RestconfDocumentedException(
 128                 String.format("Stream with name %s was not found.", streamName),
 129                 ErrorType.PROTOCOL, ErrorTag.UNKNOWN_ELEMENT));
 130
 131         final EffectiveModelContext schemaContext = handlersHolder.getSchemaHandler().get();
 132         final URI uri = prepareUriByStreamName(uriInfo, streamName);
 133         notificationListenerAdapter.setQueryParams(notificationQueryParams);
 134         notificationListenerAdapter.listen(handlersHolder.getNotificationServiceHandler());
 135         final DOMDataBroker dataBroker = handlersHolder.getDataBroker();
 136         notificationListenerAdapter.setCloseVars(dataBroker, handlersHolder.getSchemaHandler());
 137         final MapEntryNode mapToStreams = RestconfMappingNodeUtil.mapYangNotificationStreamByIetfRestconfMonitoring(
 138                     notificationListenerAdapter.getSchemaPath().lastNodeIdentifier(),
 139                     schemaContext.getNotifications(), notificationListenerAdapter.getStart(),
 140                     notificationListenerAdapter.getOutputType(), uri);
 141
 142         // FIXME: how does this correlate with the transaction notificationListenerAdapter.close() will do?
 143         final DOMDataTreeWriteTransaction writeTransaction = dataBroker.newWriteOnlyTransaction();
 144         writeDataToDS(writeTransaction, mapToStreams);
 145         submitData(writeTransaction);
 146         return uri;
 147     }
 148
 149     /**
 150      * Register listener by streamName in identifier to listen to data change notifications, and put or delete
 151      * information about listener to DS according to ietf-restconf-monitoring.
 152      *
 153      * @param identifier              Identifier as stream name.
 154      * @param uriInfo                 Base URI information.
 155      * @param notificationQueryParams Query parameters of notification.
 156      * @param handlersHolder          Holder of handlers for notifications.
 157      * @return Location for listening.
 158      */
 159     final URI subscribeToDataStream(final String identifier, final UriInfo uriInfo,
 160             final NotificationQueryParams notificationQueryParams, final HandlersHolder handlersHolder) {
 161         final Map<String, String> mapOfValues = mapValuesFromUri(identifier);
 162
 163         final String datastoreParam = mapOfValues.get(RestconfStreamsConstants.DATASTORE_PARAM_NAME);
 164         if (isNullOrEmpty(datastoreParam)) {
 165             final String message = "Stream name does not contain datastore value (pattern /datastore=)";
 166             LOG.debug(message);
 167             throw new RestconfDocumentedException(message, ErrorType.APPLICATION, ErrorTag.MISSING_ATTRIBUTE);
 168         }
 169
 170         // FIXME: this is kept only for compatibility, we are not using this parameter
 171         if (isNullOrEmpty(mapOfValues.get(RestconfStreamsConstants.SCOPE_PARAM_NAME))) {
 172             final String message = "Stream name does not contain scope value (pattern /scope=)";
 173             LOG.warn(message);
 174             throw new RestconfDocumentedException(message, ErrorType.APPLICATION, ErrorTag.MISSING_ATTRIBUTE);
 175         }
 176
 177         final String streamName = ListenersBroker.createStreamNameFromUri(identifier);
 178         final ListenerAdapter listener = ListenersBroker.getInstance().getDataChangeListenerFor(streamName)
 179             .orElseThrow(() -> new RestconfDocumentedException("No listener found for stream " + streamName,
 180                 ErrorType.APPLICATION, ErrorTag.DATA_MISSING));
 181         listener.setQueryParams(notificationQueryParams);
 182
 183         final DOMDataBroker dataBroker = handlersHolder.getDataBroker();
 184         final SchemaContextHandler schemaHandler = handlersHolder.getSchemaHandler();
 185         listener.setCloseVars(dataBroker, schemaHandler);
 186         listener.listen(dataBroker, LogicalDatastoreType.valueOf(datastoreParam));
 187
 188         final URI uri = prepareUriByStreamName(uriInfo, streamName);
 189         final EffectiveModelContext schemaContext = schemaHandler.get();
 190         final String serializedPath = IdentifierCodec.serialize(listener.getPath(), schemaContext);
 191
 192         final MapEntryNode mapToStreams =
 193             RestconfMappingNodeUtil.mapDataChangeNotificationStreamByIetfRestconfMonitoring(listener.getPath(),
 194                 listener.getStart(), listener.getOutputType(), uri, schemaContext, serializedPath);
 195         final DOMDataTreeWriteTransaction writeTransaction = dataBroker.newWriteOnlyTransaction();
 196         writeDataToDS(writeTransaction, mapToStreams);
 197         submitData(writeTransaction);
 198         return uri;
 199     }
 200
 201     // FIXME: callers are utter duplicates, refactor them
 202     private static void writeDataToDS(final DOMDataTreeWriteOperations tx, final MapEntryNode mapToStreams) {
 203         // FIXME: use put() here
 204         tx.merge(LogicalDatastoreType.OPERATIONAL, Rfc8040.restconfStateStreamPath(mapToStreams.getIdentifier()),
 205             mapToStreams);
 206     }
 207
 208     private static void submitData(final DOMDataTreeWriteTransaction readWriteTransaction) {
 209         try {
 210             readWriteTransaction.commit().get();
 211         } catch (final InterruptedException | ExecutionException e) {
 212             throw new RestconfDocumentedException("Problem while putting data to DS.", e);
 213         }
 214     }
 215
 216     /**
 217      * Prepare map of URI parameter-values.
 218      *
 219      * @param identifier String identification of URI.
 220      * @return Map od URI parameters and values.
 221      */
 222     private static Map<String, String> mapValuesFromUri(final String identifier) {
 223         final HashMap<String, String> result = new HashMap<>();
 224         for (final String token : RestconfConstants.SLASH_SPLITTER.split(identifier)) {
 225             final String[] paramToken = token.split("=");
 226             if (paramToken.length == 2) {
 227                 result.put(paramToken[0], paramToken[1]);
 228             }
 229         }
 230         return result;
 231     }
 232 }