fw: access strategy

refs #1999

Change-Id: I5fc284d7ae82ed933bf5937d5c687885e73c3e0a
diff --git a/tests/daemon/fw/access-strategy.cpp b/tests/daemon/fw/access-strategy.cpp
new file mode 100644
index 0000000..934dfcd
--- /dev/null
+++ b/tests/daemon/fw/access-strategy.cpp
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+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2015,  Regents of the University of California,
+ *                           Arizona Board of Regents,
+ *                           Colorado State University,
+ *                           University Pierre & Marie Curie, Sorbonne University,
+ *                           Washington University in St. Louis,
+ *                           Beijing Institute of Technology,
+ *                           The University of Memphis.
+ *
+ * This file is part of NFD (Named Data Networking Forwarding Daemon).
+ * See AUTHORS.md for complete list of NFD authors and contributors.
+ *
+ * NFD is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * NFD 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "fw/access-strategy.hpp"
+
+#include "tests/test-common.hpp"
+#include "topology-tester.hpp"
+
+namespace nfd {
+namespace tests {
+
+// This test suite tests AccessStrategy's behavior as a black box,
+// without accessing its internals.
+//
+// Many test assertions are qualitative rather than quantitative.
+// They capture the design highlights of the strategy without requiring a definite value,
+// so that the test suite is not fragile to minor changes in the strategy implementation.
+//
+// Topology graphes in this test suite are shown in ASCII art,
+// in a style similar to ns-3 and ndnSIM examples.
+// They are enclosed in multi-line comments, which is an intentional violation of
+// code style rule 3.25. This is necessary because some lines ends with '\' which
+// would cause "multi-line comment" compiler warning if '//' comments are used.
+
+BOOST_FIXTURE_TEST_SUITE(FwAccessStrategy, UnitTestTimeFixture)
+
+class TwoLaptopsFixture : public UnitTestTimeFixture
+{
+protected:
+  TwoLaptopsFixture()
+  {
+    /*
+     *                  +--------+
+     *           +----->| router |<------+
+     *           |      +--------+       |
+     *      10ms |                       | 20ms
+     *           v                       v
+     *      +---------+             +---------+
+     *      | laptopA |             | laptopB |
+     *      +---------+             +---------+
+     */
+
+    router = topo.addForwarder();
+    laptopA = topo.addForwarder();
+    laptopB = topo.addForwarder();
+
+    topo.setStrategy<fw::AccessStrategy>(router);
+
+    linkA = topo.addLink(time::milliseconds(10), {router, laptopA});
+    linkB = topo.addLink(time::milliseconds(20), {router, laptopB});
+  }
+
+protected:
+  TopologyTester topo;
+
+  TopologyNode router;
+  TopologyNode laptopA;
+  TopologyNode laptopB;
+  shared_ptr<TopologyLink> linkA;
+  shared_ptr<TopologyLink> linkB;
+};
+
+BOOST_FIXTURE_TEST_CASE(OneProducer, TwoLaptopsFixture)
+{
+  /*
+   *             /------------------\
+   *             | intervalConsumer |
+   *             \------------------/
+   *                      ^ v
+   *                      | v /laptops/A
+   *                      |
+   *                      v
+   *      /laptops << +--------+ >> /laptops
+   *           +----->| router |<------+
+   *           |      +--------+       |
+   *      10ms |                       | 20ms
+   *           v                       v
+   *      +---------+             +---------+
+   *      | laptopA |             | laptopB |
+   *      +---------+             +---------+
+   *           ^  v
+   *           |  v /laptops/A
+   *           v
+   *    /--------------\
+   *    | echoProducer |
+   *    \--------------/
+   */
+
+  // two laptops have same prefix in router FIB
+  topo.registerPrefix(router, linkA->getFace(router), "ndn:/laptops");
+  topo.registerPrefix(router, linkB->getFace(router), "ndn:/laptops");
+
+  shared_ptr<TopologyAppLink> producer = topo.addAppFace(laptopA, "ndn:/laptops/A");
+  topo.addEchoProducer(*producer->getClientFace());
+
+  shared_ptr<TopologyAppLink> consumer = topo.addAppFace(router);
+  topo.addIntervalConsumer(*consumer->getClientFace(), "ndn:/laptops/A",
+                           time::milliseconds(100), 100);
+
+  this->advanceClocks(time::milliseconds(5), time::seconds(12));
+
+  // most Interests should be satisfied, and few Interests can go to wrong laptop
+  BOOST_CHECK_GE(consumer->getForwarderFace()->m_sentDatas.size(), 97);
+  BOOST_CHECK_GE(linkA->getFace(router)->m_sentInterests.size(), 97);
+  BOOST_CHECK_LE(linkB->getFace(router)->m_sentInterests.size(), 5);
+}
+
+BOOST_FIXTURE_TEST_CASE(FastSlowProducer, TwoLaptopsFixture)
+{
+  /*
+   *             /------------------\
+   *             | intervalConsumer |
+   *             \------------------/
+   *                      ^ v
+   *                      | v /laptops/BOTH
+   *                      |
+   *                      v
+   *      /laptops << +--------+ >> /laptops
+   *           +----->| router |<------+
+   *           |      +--------+       |
+   *      10ms |                       | 20ms
+   *           v                       v
+   *      +---------+             +---------+
+   *      | laptopA |             | laptopB |
+   *      +---------+             +---------+
+   *           ^  v                    ^  v
+   *           |  v /laptops/BOTH      |  v /laptops/BOTH
+   *           v                       v
+   *    /--------------\        /--------------\
+   *    | echoProducer |        | echoProducer |
+   *    \--------------/        \--------------/
+   */
+
+  // two laptops have same prefix in router FIB
+  topo.registerPrefix(router, linkA->getFace(router), "ndn:/laptops");
+  topo.registerPrefix(router, linkB->getFace(router), "ndn:/laptops");
+
+  shared_ptr<TopologyAppLink> producerA = topo.addAppFace(laptopA, "ndn:/laptops/BOTH");
+  topo.addEchoProducer(*producerA->getClientFace());
+  shared_ptr<TopologyAppLink> producerB = topo.addAppFace(laptopB, "ndn:/laptops/BOTH");
+  topo.addEchoProducer(*producerB->getClientFace());
+
+  shared_ptr<TopologyAppLink> consumer = topo.addAppFace(router);
+  topo.addIntervalConsumer(*consumer->getClientFace(), "ndn:/laptops/BOTH",
+                           time::milliseconds(100), 100);
+
+  this->advanceClocks(time::milliseconds(5), time::seconds(12));
+
+  // most Interests should be satisfied, and few Interests can go to slower laptopB
+  BOOST_CHECK_GE(consumer->getForwarderFace()->m_sentDatas.size(), 97);
+  BOOST_CHECK_GE(linkA->getFace(router)->m_sentInterests.size(), 90);
+  BOOST_CHECK_LE(linkB->getFace(router)->m_sentInterests.size(), 15);
+}
+
+BOOST_FIXTURE_TEST_CASE(ProducerMobility, TwoLaptopsFixture)
+{
+  /*
+   *           /------------------\                              /------------------\
+   *           | intervalConsumer |                              | intervalConsumer |
+   *           \------------------/              A               \------------------/
+   *                    ^ v                      f                        ^ v
+   *                    | v /laptops/M           t                        | v /laptops/M
+   *                    |                        e                        |
+   *                    v                        r                        v
+   *    /laptops << +--------+ >> /laptops                /laptops << +--------+ >> /laptops
+   *         +----->| router |<------+           6             +----->| router |<------+
+   *         |      +--------+       |                         |      +--------+       |
+   *    10ms |                       | 20ms  === s ==>    10ms |                       | 20ms
+   *         v                       v           e             v                       v
+   *    +---------+             +---------+      c        +---------+             +---------+
+   *    | laptopA |             | laptopB |      o        | laptopA |             | laptopB |
+   *    +---------+             +---------+      n        +---------+             +---------+
+   *         ^  v                                d                                  v  ^
+   *         |  v /laptops/M                     s                       /laptops/M v  |
+   *         v                                                                         v
+   *  /--------------\                                                          /--------------\
+   *  | echoProducer |                                                          | echoProducer |
+   *  \--------------/                                                          \--------------/
+   */
+
+  // two laptops have same prefix in router FIB
+  topo.registerPrefix(router, linkA->getFace(router), "ndn:/laptops");
+  topo.registerPrefix(router, linkB->getFace(router), "ndn:/laptops");
+
+  shared_ptr<TopologyAppLink> producerA = topo.addAppFace(laptopA, "ndn:/laptops/M");
+  topo.addEchoProducer(*producerA->getClientFace());
+  shared_ptr<TopologyAppLink> producerB = topo.addAppFace(laptopB, "ndn:/laptops/M");
+  topo.addEchoProducer(*producerB->getClientFace());
+
+  shared_ptr<TopologyAppLink> consumer = topo.addAppFace(router);
+  topo.addIntervalConsumer(*consumer->getClientFace(), "ndn:/laptops/M",
+                           time::milliseconds(100), 100);
+
+  // producer is initially on laptopA
+  producerB->fail();
+  this->advanceClocks(time::milliseconds(5), time::seconds(6));
+
+  // few Interests can go to laptopB
+  BOOST_CHECK_LE(linkB->getFace(router)->m_sentInterests.size(), 5);
+
+  // producer moves to laptopB
+  producerA->fail();
+  producerB->recover();
+  linkA->getFace(router)->m_sentInterests.clear();
+  this->advanceClocks(time::milliseconds(5), time::seconds(6));
+
+  // few additional Interests can go to laptopA
+  BOOST_CHECK_LE(linkA->getFace(router)->m_sentInterests.size(), 5);
+
+  // most Interests should be satisfied
+  BOOST_CHECK_GE(consumer->getForwarderFace()->m_sentDatas.size(), 97);
+}
+
+BOOST_FIXTURE_TEST_CASE(Bidirectional, TwoLaptopsFixture)
+{
+  /*
+   *                         /laptops << +--------+ >> /laptops
+   *                              +----->| router |<------+
+   *                              |      +--------+       |
+   *                      ^  10ms |                       | 20ms  ^
+   *                    / ^       v                       v       ^ /
+   *                         +---------+             +---------+
+   *                  +----->| laptopA |             | laptopB |<------------+
+   *                  |      +---------+             +---------+             |
+   *                  |           ^  v /laptops/A         ^  v /laptops/B    |
+   *               ^  |           |  v                    |  v               |  ^
+   *    /laptops/B ^  v           v                       v                  v  ^ /laptops/A
+   *  /------------------\   /--------------\        /--------------\     /------------------\
+   *  | intervalConsumer |   | echoProducer |        | echoProducer |     | intervalConsumer |
+   *  \------------------/   \--------------/        \--------------/     \------------------/
+   */
+
+  // laptops have default routes toward the router
+  topo.registerPrefix(laptopA, linkA->getFace(laptopA), "ndn:/");
+  topo.registerPrefix(laptopB, linkB->getFace(laptopB), "ndn:/");
+
+  // two laptops have same prefix in router FIB
+  topo.registerPrefix(router, linkA->getFace(router), "ndn:/laptops");
+  topo.registerPrefix(router, linkB->getFace(router), "ndn:/laptops");
+
+  shared_ptr<TopologyAppLink> producerA = topo.addAppFace(laptopA, "ndn:/laptops/A");
+  topo.addEchoProducer(*producerA->getClientFace());
+  shared_ptr<TopologyAppLink> producerB = topo.addAppFace(laptopB, "ndn:/laptops/B");
+  topo.addEchoProducer(*producerB->getClientFace());
+
+  shared_ptr<TopologyAppLink> consumerAB = topo.addAppFace(laptopA);
+  topo.addIntervalConsumer(*consumerAB->getClientFace(), "ndn:/laptops/B",
+                           time::milliseconds(100), 100);
+  shared_ptr<TopologyAppLink> consumerBA = topo.addAppFace(laptopB);
+  topo.addIntervalConsumer(*consumerBA->getClientFace(), "ndn:/laptops/A",
+                           time::milliseconds(100), 100);
+
+  this->advanceClocks(time::milliseconds(5), time::seconds(12));
+
+  // most Interests should be satisfied
+  BOOST_CHECK_GE(consumerAB->getForwarderFace()->m_sentDatas.size(), 97);
+  BOOST_CHECK_GE(consumerBA->getForwarderFace()->m_sentDatas.size(), 97);
+}
+
+BOOST_FIXTURE_TEST_CASE(PacketLoss, TwoLaptopsFixture)
+{
+  /*
+   *   test case Interests
+   *           |
+   *           v
+   *      +--------+
+   *      | router |
+   *      +--------+
+   *           |  v
+   *      10ms |  v /laptops
+   *           v
+   *      +---------+
+   *      | laptopA |
+   *      +---------+
+   *           ^  v
+   *           |  v /laptops/A
+   *           v
+   *    /--------------\
+   *    | echoProducer |
+   *    \--------------/
+   */
+
+  // laptopA has prefix in router FIB; laptopB is unused in this test case
+  topo.registerPrefix(router, linkA->getFace(router), "ndn:/laptops");
+
+  shared_ptr<TopologyAppLink> producerA = topo.addAppFace(laptopA, "ndn:/laptops/A");
+  topo.addEchoProducer(*producerA->getClientFace());
+
+  shared_ptr<TopologyAppLink> consumer = topo.addAppFace(router);
+
+  // Interest 1 completes normally
+  shared_ptr<Interest> interest1 = makeInterest("ndn:/laptops/A/1");
+  bool hasData1 = false;
+  consumer->getClientFace()->expressInterest(*interest1,
+                                             bind([&hasData1] { hasData1 = true; }));
+  this->advanceClocks(time::milliseconds(5), time::seconds(1));
+  BOOST_CHECK_EQUAL(hasData1, true);
+
+  // Interest 2 experiences a packet loss on initial transmission
+  shared_ptr<Interest> interest2a = makeInterest("ndn:/laptops/A/2");
+  bool hasData2a = false, hasTimeout2a = false;
+  consumer->getClientFace()->expressInterest(*interest2a,
+                                             bind([&hasData2a] { hasData2a = true; }),
+                                             bind([&hasTimeout2a] { hasTimeout2a = true; }));
+  producerA->fail();
+  this->advanceClocks(time::milliseconds(5), time::milliseconds(60));
+  BOOST_CHECK_EQUAL(hasData2a, false);
+  BOOST_CHECK_EQUAL(hasTimeout2a, false);
+
+  // Interest 2 retransmission is suppressed
+  shared_ptr<Interest> interest2b = makeInterest("ndn:/laptops/A/2");
+  bool hasData2b = false;
+  consumer->getClientFace()->expressInterest(*interest2b,
+                                             bind([&hasData2b] { hasData2b = true; }));
+  producerA->recover();
+  this->advanceClocks(time::milliseconds(5), time::seconds(1));
+  BOOST_CHECK_EQUAL(hasData2b, false);
+
+  // Interest 2 retransmission gets through, and is answered
+  shared_ptr<Interest> interest2c = makeInterest("ndn:/laptops/A/2");
+  bool hasData2c = false;
+  consumer->getClientFace()->expressInterest(*interest2c,
+                                             bind([&hasData2c] { hasData2c = true; }));
+  this->advanceClocks(time::milliseconds(5), time::seconds(1));
+  BOOST_CHECK_EQUAL(hasData2c, true);
+}
+
+BOOST_AUTO_TEST_SUITE_END()
+
+} // namespace tests
+} // namespace nfd