qpid/cpp/src/qpid/ha/Backup.cpp

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 * to you under the Apache License, Version 2.0 (the
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#include "Backup.h"
#include "Settings.h"
#include "BrokerReplicator.h"
#include "ReplicatingSubscription.h"
#include "ConnectionExcluder.h"
#include "qpid/Url.h"
#include "qpid/amqp_0_10/Codecs.h"
#include "qpid/broker/Bridge.h"
#include "qpid/broker/Broker.h"
#include "qpid/broker/SessionHandler.h"
#include "qpid/broker/Link.h"
#include "qpid/framing/AMQP_ServerProxy.h"
#include "qpid/framing/AMQFrame.h"
#include "qpid/framing/FieldTable.h"
#include "qpid/framing/MessageTransferBody.h"
#include "qpid/types/Variant.h"

namespace qpid {
namespace ha {

using namespace framing;
using namespace broker;
using types::Variant;
using std::string;

Backup::Backup(broker::Broker& b, const Settings& s) :
    broker(b), settings(s), excluder(new ConnectionExcluder())
{
    // Empty brokerUrl means delay initialization until setUrl() is called.
    if (!s.brokerUrl.empty()) initialize(Url(s.brokerUrl));
}

void Backup::initialize(const Url& url) {
    assert(!url.empty());
    QPID_LOG(notice, "Ha: Backup started: " << url);
    string protocol = url[0].protocol.empty() ? "tcp" : url[0].protocol;
    // Declare the link
    std::pair<Link::shared_ptr, bool> result = broker.getLinks().declare(
        url[0].host, url[0].port, protocol,
        false,              // durable
        settings.mechanism, settings.username, settings.password);
    assert(result.second);  // FIXME aconway 2011-11-23: error handling
    link = result.first;
    link->setUrl(url);

    replicator.reset(new BrokerReplicator(link));
    broker.getExchanges().registerExchange(replicator);
    broker.getConnectionObservers().add(excluder);
}

void Backup::setBrokerUrl(const Url& url) {
    // Ignore empty URLs seen during start-up for some tests.
    if (url.empty()) return;
    sys::Mutex::ScopedLock l(lock);
    if (link) {                 // URL changed after we initialized.
        QPID_LOG(info, "HA: Backup failover URL set to " << url);
        link->setUrl(url);
    }
    else {
        initialize(url);        // Deferred initialization
    }
}

Backup::~Backup() {
    if (link) link->close();
    if (replicator.get()) broker.getExchanges().destroy(replicator->getName());
    broker.getConnectionObservers().remove(excluder); // This allows client connections.
}

}} // namespace qpid::ha