QPID-1560: add support for a qpid.exclusive-binding option on direct exchange that causes the binding specified to be the only one for the given key. I.e. if there is already a binding at this exchange with this key it will be atomically updated to bind the new queue.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk/qpid@732297 13f79535-47bb-0310-9956-ffa450edef68

3 files changed, 48 insertions, 3 deletions

diff --git a/cpp/src/qpid/broker/DirectExchange.cpp b/cpp/src/qpid/broker/DirectExchange.cpp
index 2eb488de67..d1d9ad07e4 100644
--- a/cpp/src/qpid/broker/DirectExchange.cpp
+++ b/cpp/src/qpid/broker/DirectExchange.cpp
@@ -33,6 +33,7 @@ namespace
 const std::string qpidFedOp("qpid.fed.op");
 const std::string qpidFedTags("qpid.fed.tags");
 const std::string qpidFedOrigin("qpid.fed.origin");
+const std::string qpidExclusiveBinding("qpid.exclusive-binding");
 
 const std::string fedOpBind("B");
 const std::string fedOpUnbind("U");
@@ -56,15 +57,25 @@ DirectExchange::DirectExchange(const string& _name, bool _durable,
 
 bool DirectExchange::bind(Queue::shared_ptr queue, const string& routingKey, const FieldTable* args)
 {
-    string fedOp(args ? args->getAsString(qpidFedOp) : fedOpBind);
-    string fedTags(args ? args->getAsString(qpidFedTags) : "");
-    string fedOrigin(args ? args->getAsString(qpidFedOrigin) : "");
+    string fedOp(fedOpBind);
+    string fedTags;
+    string fedOrigin;
+    bool exclusiveBinding = false;
+    if (args) {
+        fedOp = args->getAsString(qpidFedOp);
+        fedTags = args->getAsString(qpidFedTags);
+        fedOrigin = args->getAsString(qpidFedOrigin);
+        exclusiveBinding = args->get(qpidExclusiveBinding);
+    }
+
     bool propagate = false;
 
     if (args == 0 || fedOp.empty() || fedOp == fedOpBind) {
         Mutex::ScopedLock l(lock);
         Binding::shared_ptr b(new Binding(routingKey, queue, this, FieldTable(), fedOrigin));
         BoundKey& bk = bindings[routingKey];
+        if (exclusiveBinding) bk.queues.clear();
+
         if (bk.queues.add_unless(b, MatchQueue(queue))) {
             propagate = bk.fedBinding.addOrigin(fedOrigin);
             if (mgmtExchange != 0) {
diff --git a/cpp/src/qpid/sys/CopyOnWriteArray.h b/cpp/src/qpid/sys/CopyOnWriteArray.h
index c5bdcc0942..a09ee9d441 100644
--- a/cpp/src/qpid/sys/CopyOnWriteArray.h
+++ b/cpp/src/qpid/sys/CopyOnWriteArray.h
@@ -64,6 +64,18 @@ public:
         }
     }
 
+    bool clear()
+    {
+        Mutex::ScopedLock l(lock);
+        if (array && !array->empty()) {
+            ArrayPtr copy;
+            array = copy;
+            return true;
+        } else {
+            return false;
+        }
+    }
+
     template <class F>
     bool add_unless(T& t, F f)
     {
diff --git a/cpp/src/tests/ClientSessionTest.cpp b/cpp/src/tests/ClientSessionTest.cpp
index 5d047dcd0e..454632dd39 100644
--- a/cpp/src/tests/ClientSessionTest.cpp
+++ b/cpp/src/tests/ClientSessionTest.cpp
@@ -447,6 +447,28 @@ QPID_AUTO_TEST_CASE(testExclusiveSubscribe)
     
 }
 
+QPID_AUTO_TEST_CASE(testExclusiveBinding) {
+    FieldTable options;
+    options.setString("qpid.exclusive-binding", "anything");
+    ClientSessionFixture fix;
+    fix.session.queueDeclare(arg::queue="queue-1", arg::exclusive=true, arg::autoDelete=true);
+    fix.session.queueDeclare(arg::queue="queue-2", arg::exclusive=true, arg::autoDelete=true);
+    fix.session.exchangeBind(arg::exchange="amq.direct", arg::queue="queue-1", arg::bindingKey="my-key", arg::arguments=options);
+    fix.session.messageTransfer(arg::destination="amq.direct", arg::content=Message("message1", "my-key"));
+    fix.session.exchangeBind(arg::exchange="amq.direct", arg::queue="queue-2", arg::bindingKey="my-key", arg::arguments=options);
+    fix.session.messageTransfer(arg::destination="amq.direct", arg::content=Message("message2", "my-key"));
+
+    Message got;
+    BOOST_CHECK(fix.subs.get(got, "queue-1"));
+    BOOST_CHECK_EQUAL("message1", got.getData());
+    BOOST_CHECK(!fix.subs.get(got, "queue-1"));
+
+    BOOST_CHECK(fix.subs.get(got, "queue-2"));
+    BOOST_CHECK_EQUAL("message2", got.getData());
+    BOOST_CHECK(!fix.subs.get(got, "queue-2"));
+}
+
+
 QPID_AUTO_TEST_SUITE_END()