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 static com.google.common.base.Preconditions.checkState;
  20 import static java.lang.String.format;
  21
  22 import com.google.common.base.Charsets;
  23 import com.google.common.io.CharStreams;
  24 import com.google.common.primitives.UnsignedInts;
  25 import com.google.inject.Inject;
  26 import io.fd.honeycomb.binding.init.ProviderTrait;
  27 import io.fd.honeycomb.data.init.ShutdownHandler;
  28 import io.fd.vpp.jvpp.JVppRegistry;
  29 import io.fd.vpp.jvpp.JVppRegistryImpl;
  30 import io.fd.vpp.jvpp.VppJNIConnection;
  31 import java.io.BufferedInputStream;
  32 import java.io.IOException;
  33 import java.io.InputStreamReader;
  34 import org.slf4j.Logger;
  35 import org.slf4j.LoggerFactory;
  36
  37 /**
  38  * Provides JVppRegistry. Must be a singleton due to shutdown hook usage. Registers shutdown hook to disconnect from
  39  * VPP.
  40  */
  41 public final class JVppRegistryProvider extends ProviderTrait<JVppRegistry> {
  42
  43     private static final Logger LOG = LoggerFactory.getLogger(JVppRegistryProvider.class);
  44
  45     @Inject
  46     private VppConfigAttributes config;
  47     @Inject
  48     private ShutdownHandler shutdownHandler;
  49
  50     private long connectedVppPid;
  51
  52     @Override
  53     protected JVppRegistry create() {
  54         final JVppRegistry registry;
  55         try {
  56             if (config.apiSegmentPrefix.isPresent()) {
  57                 // TODO(VPP-1342): JVppRegistryImpl requires full SHM region name
  58                 final String shmName = String.format("/%s-vpe-api", config.apiSegmentPrefix.get());
  59                 registry = new JVppRegistryImpl(config.jvppConnectionName, shmName);
  60             } else {
  61                 registry = new JVppRegistryImpl(config.jvppConnectionName);
  62             }
  63             connectedVppPid = initConnectedVppPid(registry);
  64             shutdownHandler.register("jvpp-registry", () -> {
  65                 // Closing JVpp connection with shutdown hook to erase the connection from VPP so HC will be able
  66                 // to connect next time. If JVM is force closed, this will not be executed and VPP connection
  67                 // with name from config will stay open and prevent next startup of HC to success
  68
  69                 LOG.info("Disconnecting from VPP");
  70
  71                 // Handles restart honeycomb service or restart vpp service
  72                 // this tells whether vpp that was honeycomb connected to is running(true) or some other instance of vpp is
  73                 // running(false). This happens when honeycomb is restarted together with vpp using && ,therefore vpp restarts
  74                 // before honeycomb shutdown starts, and keepalive does not have enough time to trigger therefore vpp
  75                 // status listener says that vpp is running. This condition prevents honeycomb to invoke disconnect on different vpp
  76                 // instance than it was connected to, which would ultimately lead to vpp being in state that is unresponsive
  77                 // to connection attempts.
  78                 if (isConnectedVppRunning(connectedVppPid)) {
  79                     registry.close();
  80                     LOG.info("Successfully disconnected from VPP as {}", config.jvppConnectionName);
  81                 } else {
  82                     // Handles restart vpp && honeycomb service
  83                     LOG.info("VPP instance used for jvpp connection is not alive anymore, no need to disconnect");
  84                 }
  85             });
  86         } catch (IOException e) {
  87             throw new IllegalStateException("Unable to open VPP management connection", e);
  88         }
  89         LOG.info("JVpp connection opened successfully as: {}", config.jvppConnectionName);
  90         return registry;
  91     }
  92
  93     /**
  94      * Tells whether vpp instance that was used for connection is still running
  95      */
  96     private static boolean isConnectedVppRunning(final long connectedVppPid) {
  97         try {
  98             final Process process = Runtime.getRuntime().exec(format("ps -eo pid|grep %s", connectedVppPid));
  99
 100             final BufferedInputStream input = new BufferedInputStream(process.getInputStream());
 101             final String processOut = CharStreams.toString(new InputStreamReader(input, Charsets.UTF_8));
 102             return processOut.trim().contains(String.valueOf(connectedVppPid));
 103         } catch (IOException e) {
 104             throw new IllegalStateException(e);
 105         }
 106     }
 107
 108     /**
 109      * Read process id of currently connected vpp
 110      */
 111     private static long initConnectedVppPid(final JVppRegistry jVppRegistry) {
 112         checkState(jVppRegistry.getConnection() instanceof VppJNIConnection, "Connection is not %s", VppJNIConnection.class);
 113         final VppJNIConnection jniConnection = VppJNIConnection.class.cast(jVppRegistry.getConnection());
 114         final VppJNIConnection.ConnectionInfo jniConnectionInfo = VppJNIConnection.ConnectionInfo.class.cast(
 115                 jniConnection.getConnectionInfo());
 116
 117         return UnsignedInts.toLong(jniConnectionInfo.pid);
 118     }
 119 }