restconf/restconf-nb-rfc8040/src/main/java/org/opendaylight/restconf/nb/rfc8040/streams/websockets/WebSocketFactory.java

   1 /*
   2  * Copyright © 2019 FRINX s.r.o. 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.restconf.nb.rfc8040.streams.websockets;
  10
  11 import java.util.Optional;
  12 import java.util.concurrent.ScheduledExecutorService;
  13 import javax.servlet.http.HttpServletResponse;
  14 import org.eclipse.jetty.websocket.servlet.ServletUpgradeRequest;
  15 import org.eclipse.jetty.websocket.servlet.ServletUpgradeResponse;
  16 import org.eclipse.jetty.websocket.servlet.WebSocketCreator;
  17 import org.opendaylight.restconf.nb.rfc8040.streams.listeners.BaseListenerInterface;
  18 import org.opendaylight.restconf.nb.rfc8040.streams.listeners.ListenersBroker;
  19 import org.slf4j.Logger;
  20 import org.slf4j.LoggerFactory;
  21
  22 /**
  23  * Factory that is used for creation of new web-sockets based on HTTP/HTTPS upgrade request.
  24  */
  25 class WebSocketFactory implements WebSocketCreator {
  26
  27     private static final Logger LOG = LoggerFactory.getLogger(WebSocketFactory.class);
  28
  29     private final ScheduledExecutorService executorService;
  30     private final ListenersBroker listenersBroker = ListenersBroker.getInstance();
  31     private final int maximumFragmentLength;
  32     private final int heartbeatInterval;
  33
  34     /**
  35      * Creation of the web-socket factory.
  36      *
  37      * @param executorService       Executor for creation of threads for controlling of web-socket sessions.
  38      * @param maximumFragmentLength Maximum web-socket fragment length in number of Unicode code units (characters)
  39      *                              (exceeded message length leads to fragmentation of messages).
  40      * @param heartbeatInterval     Interval in milliseconds between sending of ping control frames.
  41      */
  42     WebSocketFactory(final ScheduledExecutorService executorService, final int maximumFragmentLength,
  43             final int heartbeatInterval) {
  44         this.executorService = executorService;
  45         this.maximumFragmentLength = maximumFragmentLength;
  46         this.heartbeatInterval = heartbeatInterval;
  47     }
  48
  49     /**
  50      * Creation of the new web-socket based on input HTTP/HTTPS upgrade request. Web-socket is created only if the
  51      * data listener for input URI can be found (results in status code 101); otherwise status code 404 is set
  52      * in upgrade response.
  53      *
  54      * @param servletUpgradeRequest  Upgrade request.
  55      * @param servletUpgradeResponse Upgrade response.
  56      * @return Created web-socket instance or {@code null} if the web-socket cannot be created.
  57      */
  58     @Override
  59     public Object createWebSocket(final ServletUpgradeRequest servletUpgradeRequest,
  60             final ServletUpgradeResponse servletUpgradeResponse) {
  61         final String requestUri = servletUpgradeRequest.getRequestURI().getRawPath();
  62         final String streamName = ListenersBroker.createStreamNameFromUri(requestUri);
  63
  64         final Optional<BaseListenerInterface> listener = listenersBroker.getListenerFor(streamName);
  65         if (listener.isPresent()) {
  66             LOG.debug("Listener for stream with name {} has been found, web-socket session handler will be created.",
  67                     streamName);
  68             servletUpgradeResponse.setSuccess(true);
  69             servletUpgradeResponse.setStatusCode(HttpServletResponse.SC_SWITCHING_PROTOCOLS);
  70             // note: every web-socket manages PING process individually because this approach scales better than sending
  71             // of PING frames at once over all web-socket sessions
  72             return new WebSocketSessionHandler(executorService, listener.get(), maximumFragmentLength,
  73                     heartbeatInterval);
  74         } else {
  75             LOG.debug("Listener for stream with name {} was not found.", streamName);
  76             servletUpgradeResponse.setSuccess(false);
  77             servletUpgradeResponse.setStatusCode(HttpServletResponse.SC_NOT_FOUND);
  78             return null;
  79         }
  80     }
  81 }