library/impl/src/main/java/org/opendaylight/ovsdb/lib/jsonrpc/JsonRpcEndpoint.java

   1 /*
   2  * Copyright (c) 2013, 2015 EBay Software Foundation 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.ovsdb.lib.jsonrpc;
  10
  11 import com.fasterxml.jackson.core.JsonProcessingException;
  12 import com.fasterxml.jackson.databind.JavaType;
  13 import com.fasterxml.jackson.databind.JsonNode;
  14 import com.fasterxml.jackson.databind.ObjectMapper;
  15 import com.fasterxml.jackson.databind.type.TypeFactory;
  16 import com.google.common.collect.Maps;
  17 import com.google.common.reflect.Invokable;
  18 import com.google.common.reflect.Reflection;
  19 import com.google.common.reflect.TypeToken;
  20 import com.google.common.util.concurrent.ListenableFuture;
  21 import com.google.common.util.concurrent.SettableFuture;
  22 import com.google.common.util.concurrent.ThreadFactoryBuilder;
  23 import io.netty.channel.Channel;
  24 import java.lang.reflect.InvocationHandler;
  25 import java.lang.reflect.InvocationTargetException;
  26 import java.lang.reflect.Method;
  27 import java.util.List;
  28 import java.util.Map;
  29 import java.util.UUID;
  30 import java.util.concurrent.Executors;
  31 import java.util.concurrent.ScheduledExecutorService;
  32 import java.util.concurrent.ThreadFactory;
  33 import java.util.concurrent.TimeUnit;
  34
  35 import org.opendaylight.ovsdb.lib.error.UnexpectedResultException;
  36 import org.opendaylight.ovsdb.lib.error.UnsupportedArgumentException;
  37 import org.opendaylight.ovsdb.lib.message.OvsdbRPC;
  38 import org.slf4j.Logger;
  39 import org.slf4j.LoggerFactory;
  40
  41 public class JsonRpcEndpoint {
  42
  43     private static final Logger LOG = LoggerFactory.getLogger(JsonRpcEndpoint.class);
  44     private static final int REAPER_THREADS = 3;
  45     private static final ThreadFactory FUTURE_REAPER_THREAD_FACTORY = new ThreadFactoryBuilder()
  46             .setNameFormat("OVSDB-Lib-Future-Reaper-%d").build();
  47     private static final ScheduledExecutorService FUTURE_REAPER_SERVICE
  48             = Executors.newScheduledThreadPool(REAPER_THREADS, FUTURE_REAPER_THREAD_FACTORY);
  49
  50     private static int reaperInterval = 1000;
  51
  52     public class CallContext {
  53         Method method;
  54         JsonRpc10Request request;
  55         SettableFuture<Object> future;
  56
  57         public CallContext(JsonRpc10Request request, Method method, SettableFuture<Object> future) {
  58             this.method = method;
  59             this.request = request;
  60             this.future = future;
  61         }
  62
  63         public Method getMethod() {
  64             return method;
  65         }
  66
  67         public JsonRpc10Request getRequest() {
  68             return request;
  69         }
  70
  71         public SettableFuture<Object> getFuture() {
  72             return future;
  73         }
  74     }
  75
  76     ObjectMapper objectMapper;
  77     Channel nettyChannel;
  78     Map<String, CallContext> methodContext = Maps.newHashMap();
  79     Map<Object, OvsdbRPC.Callback> requestCallbacks = Maps.newHashMap();
  80
  81     public JsonRpcEndpoint(ObjectMapper objectMapper, Channel channel) {
  82         this.objectMapper = objectMapper;
  83         this.nettyChannel = channel;
  84     }
  85
  86     public <T> T getClient(final Object context, Class<T> klazz) {
  87
  88         return Reflection.newProxy(klazz, new InvocationHandler() {
  89             @Override
  90             public Object invoke(Object proxy, Method method, Object[] args) throws Exception {
  91                 if (method.getName().equals(OvsdbRPC.REGISTER_CALLBACK_METHOD)) {
  92                     if ((args == null) || args.length != 1 || !(args[0] instanceof OvsdbRPC.Callback)) {
  93                         return false;
  94                     }
  95                     requestCallbacks.put(context, (OvsdbRPC.Callback)args[0]);
  96                     return true;
  97                 }
  98
  99                 JsonRpc10Request request = new JsonRpc10Request(UUID.randomUUID().toString());
 100                 request.setMethod(method.getName());
 101
 102                 if (args != null && args.length != 0) {
 103                     List<Object> params = null;
 104
 105                     if (args.length == 1) {
 106                         if (args[0] instanceof Params) {
 107                             params = ((Params) args[0]).params();
 108                         } else if (args[0] instanceof List) {
 109                             params = (List<Object>) args[0];
 110                         }
 111
 112                         if (params == null) {
 113                             throw new UnsupportedArgumentException("do not understand this argument yet");
 114                         }
 115                         request.setParams(params);
 116                     }
 117                 }
 118
 119                 String requestString = objectMapper.writeValueAsString(request);
 120                 LOG.trace("getClient Request : {}", requestString);
 121
 122                 SettableFuture<Object> sf = SettableFuture.create();
 123                 methodContext.put(request.getId(), new CallContext(request, method, sf));
 124                 FUTURE_REAPER_SERVICE.schedule(new Runnable() {
 125                     @Override
 126                     public void run() {
 127                         CallContext cc = methodContext.remove(request.getId());
 128                         if ( cc != null) {
 129                             if ( cc.getFuture().isDone() || cc.getFuture().isCancelled()) {
 130                                 return;
 131                             }
 132                             cc.getFuture().cancel(false);
 133                         }
 134                     }
 135                 }, reaperInterval, TimeUnit.MILLISECONDS);
 136
 137                 nettyChannel.writeAndFlush(requestString);
 138
 139                 return sf;
 140             }
 141         }
 142         );
 143     }
 144
 145     public void processResult(JsonNode response) throws NoSuchMethodException {
 146
 147         LOG.trace("Response : {}", response.toString());
 148         CallContext returnCtxt = methodContext.remove(response.get("id").asText());
 149         if (returnCtxt == null) {
 150             return;
 151         }
 152
 153         if (ListenableFuture.class == returnCtxt.getMethod().getReturnType()) {
 154             TypeToken<?> retType = TypeToken.of(
 155                     returnCtxt.getMethod().getGenericReturnType())
 156                     .resolveType(ListenableFuture.class.getMethod("get").getGenericReturnType());
 157             JavaType javaType =  TypeFactory.defaultInstance().constructType(retType.getType());
 158
 159             JsonNode result = response.get("result");
 160             Object result1 = objectMapper.convertValue(result, javaType);
 161             JsonNode error = response.get("error");
 162             if (error != null && !error.isNull()) {
 163                 LOG.error("Error : {}", error.toString());
 164             }
 165
 166             returnCtxt.getFuture().set(result1);
 167
 168         } else {
 169             throw new UnexpectedResultException("Don't know how to handle this");
 170         }
 171     }
 172
 173     public void processRequest(Object context, JsonNode requestJson) {
 174         JsonRpc10Request request = new JsonRpc10Request(requestJson.get("id").asText());
 175         request.setMethod(requestJson.get("method").asText());
 176         LOG.trace("Request : {} {} {}", requestJson.get("id"), requestJson.get("method"),
 177                 requestJson.get("params"));
 178         OvsdbRPC.Callback callback = requestCallbacks.get(context);
 179         if (callback != null) {
 180             Method[] methods = callback.getClass().getDeclaredMethods();
 181             for (Method method : methods) {
 182                 if (method.getName().equals(request.getMethod())) {
 183                     Class<?>[] parameters = method.getParameterTypes();
 184                     JsonNode params = requestJson.get("params");
 185                     Object param = objectMapper.convertValue(params, parameters[1]);
 186                     try {
 187                         Invokable from = Invokable.from(method);
 188                         from.setAccessible(true);
 189                         from.invoke(callback, context, param);
 190                     } catch (IllegalAccessException | InvocationTargetException e) {
 191                         LOG.error("Unable to invoke callback {}", method.getName(), e);
 192                     }
 193                     return;
 194                 }
 195             }
 196         }
 197
 198         // Echo dont need any special processing. hence handling it internally.
 199
 200         if (request.getMethod().equals("echo")) {
 201             JsonRpc10Response response = new JsonRpc10Response(request.getId());
 202             response.setError(null);
 203             String jsonString = null;
 204             try {
 205                 jsonString = objectMapper.writeValueAsString(response);
 206                 nettyChannel.writeAndFlush(jsonString);
 207             } catch (JsonProcessingException e) {
 208                 LOG.error("Exception while processing JSON string {}", jsonString, e);
 209             }
 210             return;
 211         }
 212
 213         // send a null response for list_dbs
 214         if (request.getMethod().equals("list_dbs")) {
 215             JsonRpc10Response response = new JsonRpc10Response(request.getId());
 216             response.setError(null);
 217             String jsonString = null;
 218             try {
 219                 jsonString = objectMapper.writeValueAsString(response);
 220                 nettyChannel.writeAndFlush(jsonString);
 221             } catch (JsonProcessingException e) {
 222                 LOG.error("Exception while processing JSON string {}", jsonString, e);
 223             }
 224             return;
 225         }
 226
 227         LOG.error("No handler for Request : {} on {}", requestJson.toString(), context);
 228     }
 229
 230     public Map<String, CallContext> getMethodContext() {
 231         return methodContext;
 232     }
 233
 234     public static void setReaperInterval(int interval) {
 235         reaperInterval = interval;
 236         LOG.info("Ovsdb Rpc Task interval is set to {} millisecond", reaperInterval);
 237     }
 238 }