Allow addition and removal of individual routes via REST.

ONOS-6919

Change-Id: I7c851c92d495b42a9e0948f739859f46eb2ded7a
diff --git a/apps/route-service/app/src/main/java/org/onosproject/routeservice/rest/RouteCodec.java b/apps/route-service/app/src/main/java/org/onosproject/routeservice/rest/RouteCodec.java
new file mode 100644
index 0000000..3ea9f07
--- /dev/null
+++ b/apps/route-service/app/src/main/java/org/onosproject/routeservice/rest/RouteCodec.java
@@ -0,0 +1,62 @@
+/*
+ * Copyright 2017-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.onosproject.routeservice.rest;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onlab.packet.IpAddress;
+import org.onlab.packet.IpPrefix;
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+import org.onosproject.routeservice.Route;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Codec to encode and decode a unicast route to and from JSON.
+ */
+public class RouteCodec extends JsonCodec<Route> {
+
+    private static final String SOURCE = "source";
+    private static final String PREFIX = "prefix";
+    private static final String NEXT_HOP = "nextHop";
+
+    @Override
+    public ObjectNode encode(Route route, CodecContext context) {
+        checkNotNull(route);
+        ObjectNode root = context.mapper().createObjectNode()
+                .put(SOURCE, route.source().toString())
+                .put(PREFIX, route.prefix().toString())
+                .put(NEXT_HOP, route.nextHop().toString());
+
+        return root;
+    }
+
+    @Override
+    public Route decode(ObjectNode json, CodecContext context) {
+        if (json == null || !json.isObject()) {
+            return null;
+        }
+
+        IpPrefix prefix = IpPrefix.valueOf(json.path(PREFIX).asText());
+        IpAddress nextHop = IpAddress.valueOf(json.path(NEXT_HOP).asText());
+
+        // Routes through the REST API are created as STATIC, so we ignore
+        // the source parameter if it is specified in the JSON.
+        Route route = new Route(Route.Source.STATIC, prefix, nextHop);
+
+        return route;
+    }
+}