Add Update Handler class
Change-Id: I465297bfa3b8c4c8e6e7f7cd028b2d4afeb4e768
Refs: #3598
diff --git a/src/update-handler.hpp b/src/update-handler.hpp
new file mode 100644
index 0000000..c1177df
--- /dev/null
+++ b/src/update-handler.hpp
@@ -0,0 +1,158 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+* Copyright (c) 2016 Regents of the University of California.
+*
+* This file is part of the nTorrent codebase.
+*
+* nTorrent is free software: you can redistribute it and/or modify it under the
+* terms of the GNU Lesser General Public License as published by the Free Software
+* Foundation, either version 3 of the License, or (at your option) any later version.
+*
+* nTorrent is distributed in the hope that it will be useful, but WITHOUT ANY
+* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+* PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
+*
+* You should have received copies of the GNU General Public License and GNU Lesser
+* General Public License along with nTorrent, e.g., in COPYING.md file. If not, see
+* <http://www.gnu.org/licenses/>.
+*
+* See AUTHORS for complete list of nTorrent authors and contributors.
+*/
+
+#ifndef UPDATE_HANDLER_H
+#define UPDATE_HANDLER_H
+
+#include "stats-table.hpp"
+
+#include <ndn-cxx/face.hpp>
+#include <ndn-cxx/interest.hpp>
+#include <ndn-cxx/security/key-chain.hpp>
+
+namespace ndn {
+namespace ntorrent {
+
+class UpdateHandler {
+public:
+ class Error : public tlv::Error
+ {
+ public:
+ explicit
+ Error(const std::string& what)
+ : tlv::Error(what)
+ {
+ }
+ };
+
+ UpdateHandler(Name torrentName, shared_ptr<KeyChain> keyChain,
+ shared_ptr<StatsTable> statsTable, shared_ptr<Face> face);
+
+ ~UpdateHandler();
+
+ /**
+ * @brief Send an ALIVE Interest
+ * @param routablePrefix The routable prefix to be included in the LINK object attached
+ * to this Interest
+ */
+ void
+ sendAliveInterest(StatsTable::iterator iter);
+
+ /**
+ * @brief Check whether we need to send out an "ALIVE" interest
+ * @return True if an "ALIVE" interest should be sent out, otherwise false
+ *
+ * Returns true if we have less than MIN_NUM_OF_ROUTABLE_NAMES prefixes in the stats table
+ * or all the routable prefixes has success rate less than 0.5. Otherwise, it returns false
+ */
+ bool
+ needsUpdate();
+
+ enum {
+ // Maximum number of names to be encoded as a response to an "ALIVE" Interest
+ MAX_NUM_OF_ENCODED_NAMES = 5,
+ // Minimum number of routable prefixes that the peer would like to have
+ MIN_NUM_OF_ROUTABLE_NAMES = 5,
+ };
+
+protected:
+ // Used for testing purposes
+ const Name&
+ getOwnRoutablePrefix();
+
+private:
+ template<encoding::Tag TAG>
+ size_t
+ encodeContent(EncodingImpl<TAG>& encoder) const;
+
+ void
+ onInterestReceived(const InterestFilter& filter, const Interest& interest);
+
+ void
+ onRegisterFailed(const Name& prefix, const std::string& reason);
+
+ /**
+ * @brief Encode the first MAX_NUM_OF_ENCODED_NAMES prefixes of the table into a data packet
+ * @param name The name of the data packet
+ * @return A shared pointer to the created data packet
+ *
+ */
+ shared_ptr<Data>
+ createDataPacket(const Name& name);
+
+ /**
+ * @brief Given a received data packet, decode the contained routable name prefixes
+ * and insert them to the table (if not already there)
+ * @param interest The interest that retrieved the data packet
+ * @param data A shared pointer to the received data packet
+ *
+ */
+ void
+ decodeDataPacketContent(const Interest& interest, const Data& data);
+
+ /**
+ * @brief Send an Interest to the local NFD to get the routable prefixes under which the
+ * published data is available
+ */
+ void
+ learnOwnRoutablePrefix();
+
+ void
+ tryNextRoutablePrefix(const Interest& interest);
+
+private:
+ Name m_torrentName;
+ shared_ptr<KeyChain> m_keyChain;
+ shared_ptr<StatsTable> m_statsTable;
+ shared_ptr<Face> m_face;
+ Name m_ownRoutablePrefix;
+};
+
+inline
+UpdateHandler::UpdateHandler(Name torrentName, shared_ptr<KeyChain> keyChain,
+ shared_ptr<StatsTable> statsTable, shared_ptr<Face> face)
+: m_torrentName(torrentName)
+, m_keyChain(keyChain)
+, m_statsTable(statsTable)
+, m_face(face)
+{
+ this->learnOwnRoutablePrefix();
+ m_face->setInterestFilter(Name("/NTORRENT" + m_torrentName.toUri() + "/ALIVE"),
+ bind(&UpdateHandler::onInterestReceived, this, _1, _2),
+ RegisterPrefixSuccessCallback(),
+ bind(&UpdateHandler::onRegisterFailed, this, _1, _2));
+}
+
+inline
+UpdateHandler::~UpdateHandler()
+{
+}
+
+inline const Name&
+UpdateHandler::getOwnRoutablePrefix()
+{
+ return m_ownRoutablePrefix;
+}
+
+} // namespace ntorrent
+} // namespace ndn
+
+#endif // UPDATE_HANDLER_H