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.reflect.Invokable;
  17 import com.google.common.reflect.Reflection;
  18 import com.google.common.reflect.TypeToken;
  19 import com.google.common.util.concurrent.ListenableFuture;
  20 import com.google.common.util.concurrent.SettableFuture;
  21 import com.google.common.util.concurrent.ThreadFactoryBuilder;
  22 import io.netty.channel.Channel;
  23
  24 import java.lang.reflect.InvocationTargetException;
  25 import java.lang.reflect.Method;
  26 import java.util.HashMap;
  27 import java.util.List;
  28 import java.util.Map;
  29 import java.util.UUID;
  30 import java.util.concurrent.ConcurrentHashMap;
  31 import java.util.concurrent.Executors;
  32 import java.util.concurrent.ScheduledExecutorService;
  33 import java.util.concurrent.ThreadFactory;
  34 import java.util.concurrent.TimeUnit;
  35
  36 import org.opendaylight.ovsdb.lib.error.UnexpectedResultException;
  37 import org.opendaylight.ovsdb.lib.error.UnsupportedArgumentException;
  38 import org.opendaylight.ovsdb.lib.message.OvsdbRPC;
  39 import org.slf4j.Logger;
  40 import org.slf4j.LoggerFactory;
  41
  42 public class JsonRpcEndpoint {
  43
  44     private static final Logger LOG = LoggerFactory.getLogger(JsonRpcEndpoint.class);
  45     private static final int REAPER_THREADS = 3;
  46     private static final ThreadFactory FUTURE_REAPER_THREAD_FACTORY = new ThreadFactoryBuilder()
  47             .setNameFormat("OVSDB-Lib-Future-Reaper-%d")
  48             .setDaemon(true).build();
  49     private static final ScheduledExecutorService FUTURE_REAPER_SERVICE
  50             = Executors.newScheduledThreadPool(REAPER_THREADS, FUTURE_REAPER_THREAD_FACTORY);
  51
  52     private static int reaperInterval = 1000;
  53
  54     public class CallContext {
  55         Method method;
  56         JsonRpc10Request request;
  57         SettableFuture<Object> future;
  58
  59         public CallContext(JsonRpc10Request request, Method method, SettableFuture<Object> future) {
  60             this.method = method;
  61             this.request = request;
  62             this.future = future;
  63         }
  64
  65         public Method getMethod() {
  66             return method;
  67         }
  68
  69         public JsonRpc10Request getRequest() {
  70             return request;
  71         }
  72
  73         public SettableFuture<Object> getFuture() {
  74             return future;
  75         }
  76     }
  77
  78     ObjectMapper objectMapper;
  79     Channel nettyChannel;
  80     Map<String, CallContext> methodContext = new ConcurrentHashMap<>();
  81     Map<Object, OvsdbRPC.Callback> requestCallbacks = new HashMap<>();
  82
  83     public JsonRpcEndpoint(ObjectMapper objectMapper, Channel channel) {
  84         this.objectMapper = objectMapper;
  85         this.nettyChannel = channel;
  86     }
  87
  88     public <T> T getClient(final Object context, Class<T> klazz) {
  89
  90         return Reflection.newProxy(klazz, (proxy, method, args) -> {
  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(() -> {
 125                 CallContext cc = methodContext.remove(request.getId());
 126                 if (cc != null) {
 127                     if (cc.getFuture().isDone() || cc.getFuture().isCancelled()) {
 128                         return;
 129                     }
 130                     cc.getFuture().cancel(false);
 131                 }
 132             }, reaperInterval, TimeUnit.MILLISECONDS);
 133
 134             nettyChannel.writeAndFlush(requestString);
 135
 136             return sf;
 137         }
 138         );
 139     }
 140
 141     public void processResult(JsonNode response) throws NoSuchMethodException {
 142
 143         LOG.trace("Response : {}", response.toString());
 144         CallContext returnCtxt = methodContext.remove(response.get("id").asText());
 145         if (returnCtxt == null) {
 146             return;
 147         }
 148
 149         if (ListenableFuture.class == returnCtxt.getMethod().getReturnType()) {
 150             TypeToken<?> retType = TypeToken.of(
 151                     returnCtxt.getMethod().getGenericReturnType())
 152                     .resolveType(ListenableFuture.class.getMethod("get").getGenericReturnType());
 153             JavaType javaType =  TypeFactory.defaultInstance().constructType(retType.getType());
 154
 155             JsonNode result = response.get("result");
 156             Object result1 = objectMapper.convertValue(result, javaType);
 157             JsonNode error = response.get("error");
 158             if (error != null && !error.isNull()) {
 159                 LOG.error("Error : {}", error.toString());
 160             }
 161
 162             returnCtxt.getFuture().set(result1);
 163
 164         } else {
 165             throw new UnexpectedResultException("Don't know how to handle this");
 166         }
 167     }
 168
 169     public void processRequest(Object context, JsonNode requestJson) {
 170         JsonRpc10Request request = new JsonRpc10Request(requestJson.get("id").asText());
 171         request.setMethod(requestJson.get("method").asText());
 172         LOG.trace("Request : {} {} {}", requestJson.get("id"), requestJson.get("method"),
 173                 requestJson.get("params"));
 174         OvsdbRPC.Callback callback = requestCallbacks.get(context);
 175         if (callback != null) {
 176             Method[] methods = callback.getClass().getDeclaredMethods();
 177             for (Method method : methods) {
 178                 if (method.getName().equals(request.getMethod())) {
 179                     Class<?>[] parameters = method.getParameterTypes();
 180                     JsonNode params = requestJson.get("params");
 181                     Object param = objectMapper.convertValue(params, parameters[1]);
 182                     try {
 183                         Invokable from = Invokable.from(method);
 184                         from.setAccessible(true);
 185                         from.invoke(callback, context, param);
 186                     } catch (IllegalAccessException | InvocationTargetException e) {
 187                         LOG.error("Unable to invoke callback {}", method.getName(), e);
 188                     }
 189                     return;
 190                 }
 191             }
 192         }
 193
 194         // Echo dont need any special processing. hence handling it internally.
 195
 196         if (request.getMethod().equals("echo")) {
 197             JsonRpc10Response response = new JsonRpc10Response(request.getId());
 198             response.setError(null);
 199             String jsonString = null;
 200             try {
 201                 jsonString = objectMapper.writeValueAsString(response);
 202                 nettyChannel.writeAndFlush(jsonString);
 203             } catch (JsonProcessingException e) {
 204                 LOG.error("Exception while processing JSON string {}", jsonString, e);
 205             }
 206             return;
 207         }
 208
 209         // send a null response for list_dbs
 210         if (request.getMethod().equals("list_dbs")) {
 211             JsonRpc10Response response = new JsonRpc10Response(request.getId());
 212             response.setError(null);
 213             String jsonString = null;
 214             try {
 215                 jsonString = objectMapper.writeValueAsString(response);
 216                 nettyChannel.writeAndFlush(jsonString);
 217             } catch (JsonProcessingException e) {
 218                 LOG.error("Exception while processing JSON string {}", jsonString, e);
 219             }
 220             return;
 221         }
 222
 223         LOG.error("No handler for Request : {} on {}", requestJson.toString(), context);
 224     }
 225
 226     public Map<String, CallContext> getMethodContext() {
 227         return methodContext;
 228     }
 229
 230     public static void setReaperInterval(int interval) {
 231         reaperInterval = interval;
 232         LOG.info("Ovsdb Rpc Task interval is set to {} millisecond", reaperInterval);
 233     }
 234
 235     public static void close() {
 236         LOG.info("Shutting down reaper executor service");
 237         FUTURE_REAPER_SERVICE.shutdownNow();
 238     }
 239 }