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

   1 /*
   2  * Copyright © 2013, 2017 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
  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")
  47             .setDaemon(true).build();
  48     private static final ScheduledExecutorService FUTURE_REAPER_SERVICE
  49             = Executors.newScheduledThreadPool(REAPER_THREADS, FUTURE_REAPER_THREAD_FACTORY);
  50
  51     private static int reaperInterval = 1000;
  52
  53     public class CallContext {
  54         Method method;
  55         JsonRpc10Request request;
  56         SettableFuture<Object> future;
  57
  58         public CallContext(JsonRpc10Request request, Method method, SettableFuture<Object> future) {
  59             this.method = method;
  60             this.request = request;
  61             this.future = future;
  62         }
  63
  64         public Method getMethod() {
  65             return method;
  66         }
  67
  68         public JsonRpc10Request getRequest() {
  69             return request;
  70         }
  71
  72         public SettableFuture<Object> getFuture() {
  73             return future;
  74         }
  75     }
  76
  77     ObjectMapper objectMapper;
  78     Channel nettyChannel;
  79     Map<String, CallContext> methodContext = Maps.newHashMap();
  80     Map<Object, OvsdbRPC.Callback> requestCallbacks = Maps.newHashMap();
  81
  82     public JsonRpcEndpoint(ObjectMapper objectMapper, Channel channel) {
  83         this.objectMapper = objectMapper;
  84         this.nettyChannel = channel;
  85     }
  86
  87     public <T> T getClient(final Object context, Class<T> klazz) {
  88
  89         return Reflection.newProxy(klazz, (proxy, method, args) -> {
  90             if (method.getName().equals(OvsdbRPC.REGISTER_CALLBACK_METHOD)) {
  91                 if ((args == null) || args.length != 1 || !(args[0] instanceof OvsdbRPC.Callback)) {
  92                     return false;
  93                 }
  94                 requestCallbacks.put(context, (OvsdbRPC.Callback)args[0]);
  95                 return true;
  96             }
  97
  98             JsonRpc10Request request = new JsonRpc10Request(UUID.randomUUID().toString());
  99             request.setMethod(method.getName());
 100
 101             if (args != null && args.length != 0) {
 102                 List<Object> params = null;
 103
 104                 if (args.length == 1) {
 105                     if (args[0] instanceof Params) {
 106                         params = ((Params) args[0]).params();
 107                     } else if (args[0] instanceof List) {
 108                         params = (List<Object>) args[0];
 109                     }
 110
 111                     if (params == null) {
 112                         throw new UnsupportedArgumentException("do not understand this argument yet");
 113                     }
 114                     request.setParams(params);
 115                 }
 116             }
 117
 118             String requestString = objectMapper.writeValueAsString(request);
 119             LOG.trace("getClient Request : {}", requestString);
 120
 121             SettableFuture<Object> sf = SettableFuture.create();
 122             methodContext.put(request.getId(), new CallContext(request, method, sf));
 123             FUTURE_REAPER_SERVICE.schedule(() -> {
 124                 CallContext cc = methodContext.remove(request.getId());
 125                 if (cc != null) {
 126                     if (cc.getFuture().isDone() || cc.getFuture().isCancelled()) {
 127                         return;
 128                     }
 129                     cc.getFuture().cancel(false);
 130                 }
 131             }, reaperInterval, TimeUnit.MILLISECONDS);
 132
 133             nettyChannel.writeAndFlush(requestString);
 134
 135             return sf;
 136         }
 137         );
 138     }
 139
 140     public void processResult(JsonNode response) throws NoSuchMethodException {
 141
 142         LOG.trace("Response : {}", response.toString());
 143         CallContext returnCtxt = methodContext.remove(response.get("id").asText());
 144         if (returnCtxt == null) {
 145             return;
 146         }
 147
 148         if (ListenableFuture.class == returnCtxt.getMethod().getReturnType()) {
 149             TypeToken<?> retType = TypeToken.of(
 150                     returnCtxt.getMethod().getGenericReturnType())
 151                     .resolveType(ListenableFuture.class.getMethod("get").getGenericReturnType());
 152             JavaType javaType =  TypeFactory.defaultInstance().constructType(retType.getType());
 153
 154             JsonNode result = response.get("result");
 155             Object result1 = objectMapper.convertValue(result, javaType);
 156             JsonNode error = response.get("error");
 157             if (error != null && !error.isNull()) {
 158                 LOG.error("Error : {}", error.toString());
 159             }
 160
 161             returnCtxt.getFuture().set(result1);
 162
 163         } else {
 164             throw new UnexpectedResultException("Don't know how to handle this");
 165         }
 166     }
 167
 168     public void processRequest(Object context, JsonNode requestJson) {
 169         JsonRpc10Request request = new JsonRpc10Request(requestJson.get("id").asText());
 170         request.setMethod(requestJson.get("method").asText());
 171         LOG.trace("Request : {} {} {}", requestJson.get("id"), requestJson.get("method"),
 172                 requestJson.get("params"));
 173         OvsdbRPC.Callback callback = requestCallbacks.get(context);
 174         if (callback != null) {
 175             Method[] methods = callback.getClass().getDeclaredMethods();
 176             for (Method method : methods) {
 177                 if (method.getName().equals(request.getMethod())) {
 178                     Class<?>[] parameters = method.getParameterTypes();
 179                     JsonNode params = requestJson.get("params");
 180                     Object param = objectMapper.convertValue(params, parameters[1]);
 181                     try {
 182                         Invokable from = Invokable.from(method);
 183                         from.setAccessible(true);
 184                         from.invoke(callback, context, param);
 185                     } catch (IllegalAccessException | InvocationTargetException e) {
 186                         LOG.error("Unable to invoke callback {}", method.getName(), e);
 187                     }
 188                     return;
 189                 }
 190             }
 191         }
 192
 193         // Echo dont need any special processing. hence handling it internally.
 194
 195         if (request.getMethod().equals("echo")) {
 196             JsonRpc10Response response = new JsonRpc10Response(request.getId());
 197             response.setError(null);
 198             String jsonString = null;
 199             try {
 200                 jsonString = objectMapper.writeValueAsString(response);
 201                 nettyChannel.writeAndFlush(jsonString);
 202             } catch (JsonProcessingException e) {
 203                 LOG.error("Exception while processing JSON string {}", jsonString, e);
 204             }
 205             return;
 206         }
 207
 208         // send a null response for list_dbs
 209         if (request.getMethod().equals("list_dbs")) {
 210             JsonRpc10Response response = new JsonRpc10Response(request.getId());
 211             response.setError(null);
 212             String jsonString = null;
 213             try {
 214                 jsonString = objectMapper.writeValueAsString(response);
 215                 nettyChannel.writeAndFlush(jsonString);
 216             } catch (JsonProcessingException e) {
 217                 LOG.error("Exception while processing JSON string {}", jsonString, e);
 218             }
 219             return;
 220         }
 221
 222         LOG.error("No handler for Request : {} on {}", requestJson.toString(), context);
 223     }
 224
 225     public Map<String, CallContext> getMethodContext() {
 226         return methodContext;
 227     }
 228
 229     public static void setReaperInterval(int interval) {
 230         reaperInterval = interval;
 231         LOG.info("Ovsdb Rpc Task interval is set to {} millisecond", reaperInterval);
 232     }
 233
 234     public static void close() {
 235         LOG.info("Shutting down reaper executor service");
 236         FUTURE_REAPER_SERVICE.shutdownNow();
 237     }
 238 }