ONOS-688 (ONOS-1835,1836,1837) :
 - Implements features to create and remove tunnels and tunnel flow policies.
 - Implements REST API to create/show/delete tunnels and policies.
 - Supports only single instance for now.
 - Fix "apply" actions to "write" actions of all flow rules
Change-Id: I3740ed82fed8eab4ab8b03839192da72d3e223f1
diff --git a/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/TunnelCodec.java b/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/TunnelCodec.java
new file mode 100644
index 0000000..2f85afd
--- /dev/null
+++ b/apps/segmentrouting/src/main/java/org/onosproject/segmentrouting/web/TunnelCodec.java
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * 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.segmentrouting.web;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import org.onosproject.codec.CodecContext;
+import org.onosproject.codec.JsonCodec;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.onosproject.segmentrouting.DefaultTunnel;
+import org.onosproject.segmentrouting.Tunnel;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public final class TunnelCodec extends JsonCodec<Tunnel> {
+
+    // JSON field names
+    private static final String TUNNEL_ID = "tunnel_id";
+    private static final String GROUP_ID = "group_id";
+    private static final String LABEL_PATH = "label_path";
+
+    @Override
+    public ObjectNode encode(Tunnel tunnel, CodecContext context) {
+        final ObjectNode result = context.mapper().createObjectNode()
+                .put(TUNNEL_ID, tunnel.id());
+
+        result.put(GROUP_ID, tunnel.groupId());
+
+        final ArrayNode jsonLabelIds = result.putArray(LABEL_PATH);
+
+        tunnel.labelIds().forEach(label -> jsonLabelIds.add(label.intValue()));
+
+        return result;
+    }
+
+    @Override
+    public DefaultTunnel decode(ObjectNode json, CodecContext context) {
+
+        String tid = json.path(TUNNEL_ID).asText();
+        List<Integer> labels = new ArrayList<>();
+
+        if (!json.path(LABEL_PATH).isMissingNode()) {
+            ArrayNode labelArray = (ArrayNode) json.path(LABEL_PATH);
+            for (JsonNode o : labelArray) {
+                labels.add(o.asInt());
+            }
+        }
+
+        return new DefaultTunnel(tid, labels);
+    }
+
+}