gerrit.fd Code Review - hc2vpp.git/blob

   1 /*
   2  * Copyright (c) 2016 Cisco and/or its affiliates.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package io.fd.hc2vpp.common.integration;
  18
  19 import com.google.common.base.Charsets;
  20 import com.google.common.io.CharStreams;
  21 import com.google.common.primitives.UnsignedInts;
  22 import com.google.inject.Inject;
  23 import io.fd.honeycomb.binding.init.ProviderTrait;
  24 import io.fd.honeycomb.data.init.ShutdownHandler;
  25 import io.fd.vpp.jvpp.JVppRegistry;
  26 import io.fd.vpp.jvpp.JVppRegistryImpl;
  27 import io.fd.vpp.jvpp.VppJNIConnection;
  28 import org.slf4j.Logger;
  29 import org.slf4j.LoggerFactory;
  30
  31 import java.io.BufferedInputStream;
  32 import java.io.IOException;
  33 import java.io.InputStreamReader;
  34
  35 import static com.google.common.base.Preconditions.checkState;
  36 import static java.lang.String.format;
  37
  38 /**
  39  * Provides JVppRegistry. Must be a singleton due to shutdown hook usage. Registers shutdown hook to disconnect from
  40  * VPP.
  41  */
  42 public final class JVppRegistryProvider extends ProviderTrait<JVppRegistry> {
  43
  44     private static final Logger LOG = LoggerFactory.getLogger(JVppRegistryProvider.class);
  45
  46     @Inject
  47     private VppConfigAttributes config;
  48     @Inject
  49     private ShutdownHandler shutdownHandler;
  50
  51     private long connectedVppPid;
  52
  53     @Override
  54     protected JVppRegistry create() {
  55         final JVppRegistry registry;
  56         try {
  57             registry = new JVppRegistryImpl(config.jvppConnectionName);
  58             connectedVppPid = initConnectedVppPid(registry);
  59             shutdownHandler.register("jvpp-registry", () -> {
  60                 // Closing JVpp connection with shutdown hook to erase the connection from VPP so HC will be able
  61                 // to connect next time. If JVM is force closed, this will not be executed and VPP connection
  62                 // with name from config will stay open and prevent next startup of HC to success
  63
  64                 LOG.info("Disconnecting from VPP");
  65
  66                 // Handles restart honeycomb service or restart vpp service
  67                 // this tells whether vpp that was honeycomb connected to is running(true) or some other instance of vpp is
  68                 // running(false). This happens when honeycomb is restarted together with vpp using && ,therefore vpp restarts
  69                 // before honeycomb shutdown starts, and keepalive does not have enough time to trigger therefore vpp
  70                 // status listener says that vpp is running. This condition prevents honeycomb to invoke disconnect on different vpp
  71                 // instance than it was connected to, which would ultimately lead to vpp being in state that is unresponsive
  72                 // to connection attempts.
  73                 if (isConnectedVppRunning(connectedVppPid)) {
  74                     registry.close();
  75                     LOG.info("Successfully disconnected from VPP as {}", config.jvppConnectionName);
  76                 } else {
  77                     // Handles restart vpp && honeycomb service
  78                     LOG.info("VPP instance used for jvpp connection is not alive anymore, no need to disconnect");
  79                 }
  80             });
  81         } catch (IOException e) {
  82             throw new IllegalStateException("Unable to open VPP management connection", e);
  83         }
  84         LOG.info("JVpp connection opened successfully as: {}", config.jvppConnectionName);
  85         return registry;
  86     }
  87
  88     /**
  89      * Tells whether vpp instance that was used for connection is still running
  90      */
  91     private static boolean isConnectedVppRunning(final long connectedVppPid) {
  92         try {
  93             final Process process = Runtime.getRuntime().exec(format("ps -eo pid|grep %s", connectedVppPid));
  94
  95             final BufferedInputStream input = new BufferedInputStream(process.getInputStream());
  96             final String processOut = CharStreams.toString(new InputStreamReader(input, Charsets.UTF_8));
  97             return processOut.trim().contains(String.valueOf(connectedVppPid));
  98         } catch (IOException e) {
  99             throw new IllegalStateException(e);
 100         }
 101     }
 102
 103     /**
 104      * Read process id of currently connected vpp
 105      */
 106     private static long initConnectedVppPid(final JVppRegistry jVppRegistry) {
 107         checkState(jVppRegistry.getConnection() instanceof VppJNIConnection, "Connection is not %s", VppJNIConnection.class);
 108         final VppJNIConnection jniConnection = VppJNIConnection.class.cast(jVppRegistry.getConnection());
 109         final VppJNIConnection.ConnectionInfo jniConnectionInfo = VppJNIConnection.ConnectionInfo.class.cast(
 110                 jniConnection.getConnectionInfo());
 111
 112         return UnsignedInts.toLong(jniConnectionInfo.pid);
 113     }
 114 }