broker: Fixed incorrect pass-by-reference of Queue::shared_ptr in several files.

cluster: added FailoverExchange - send cluster membership to clients.
client: added FailoverListener - receive cluster updates from failover exchange.


git-svn-id: https://svn.apache.org/repos/asf/incubator/qpid/trunk/qpid@702552 13f79535-47bb-0310-9956-ffa450edef68

2 files changed, 117 insertions, 0 deletions

diff --git a/cpp/src/qpid/client/FailoverListener.cpp b/cpp/src/qpid/client/FailoverListener.cpp
new file mode 100644
index 0000000000..95c137d922
--- /dev/null
+++ b/cpp/src/qpid/client/FailoverListener.cpp
@@ -0,0 +1,59 @@
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ *
+ */
+#include "FailoverListener.h"
+
+namespace qpid {
+namespace client {
+
+static const std::string AMQ_FAILOVER("amq.failover");
+
+FailoverListener::FailoverListener(Connection c)
+    : connection(c), session(c.newSession()), subscriptions(session)
+{
+    std::string qname=AMQ_FAILOVER + "." + session.getId().getName();
+    if (session.exchangeQuery(arg::exchange=AMQ_FAILOVER).getType().empty())
+        return;                 // Failover exchange not implemented.
+    session.queueDeclare(arg::queue=qname, arg::exclusive=true, arg::autoDelete=true);
+    session.exchangeBind(arg::queue=qname, arg::exchange=AMQ_FAILOVER);
+    subscriptions.subscribe(*this, qname, FlowControl::unlimited());
+    thread = sys::Thread(subscriptions);
+}
+
+FailoverListener::~FailoverListener() {
+    subscriptions.stop();
+    if (thread.id()) thread.join();
+}
+
+void FailoverListener::received(Message& msg) {
+    sys::Mutex::ScopedLock l(lock);
+    knowBrokers.clear();
+    framing::Array urlArray;
+    msg.getHeaders().getArray("amq.failover", urlArray);
+    for (framing::Array::ValueVector::const_iterator i = urlArray.begin(); i < urlArray.end(); ++i ) 
+        knowBrokers.push_back(Url((*i)->get<std::string>()));
+}
+
+std::vector<Url> FailoverListener::getKnownBrokers() const {
+    sys::Mutex::ScopedLock l(lock);
+    return knowBrokers;
+}
+
+}} // namespace qpid::client
diff --git a/cpp/src/qpid/client/FailoverListener.h b/cpp/src/qpid/client/FailoverListener.h
new file mode 100644
index 0000000000..2c06947300
--- /dev/null
+++ b/cpp/src/qpid/client/FailoverListener.h
@@ -0,0 +1,58 @@
+#ifndef QPID_CLIENT_FAILOVERLISTENER_H
+#define QPID_CLIENT_FAILOVERLISTENER_H
+
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ *
+ */
+
+#include "qpid/client/Connection.h"
+#include "qpid/client/Session.h"
+#include "qpid/client/MessageListener.h"
+#include "qpid/client/SubscriptionManager.h"
+#include "qpid/Url.h"
+#include "qpid/sys/Mutex.h"
+#include "qpid/sys/Thread.h"
+#include <vector>
+
+namespace qpid {
+namespace client {
+
+/**
+ * @internal Listen for failover updates from the amq.failover exchange.
+ */
+class FailoverListener : public MessageListener
+{
+  public:
+    FailoverListener(Connection);
+    ~FailoverListener();
+    std::vector<Url> getKnownBrokers() const;
+    void received(Message& msg);
+    
+  private:
+    mutable sys::Mutex lock;
+    Connection connection;
+    Session session;
+    SubscriptionManager subscriptions;
+    sys::Thread thread;
+    std::vector<Url> knowBrokers;
+};
+}} // namespace qpid::client
+
+#endif  /*!QPID_CLIENT_FAILOVERLISTENER_H*/