Quick CoAP Multicast Discovery Example

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#include "qmlcoapmulticastclient.h"

#include <QCoapResourceDiscoveryReply>
#include <QLoggingCategory>

Q_LOGGING_CATEGORY(lcCoapClient, "qt.coap.client")

QmlCoapMulticastClient::QmlCoapMulticastClient(QObject *parent)
    : QCoapClient(QtCoap::SecurityMode::NoSecurity, parent)
{
    connect(this, &QCoapClient::finished, this,
            [this](QCoapReply *reply) {
                    if (reply)
                        emit finished(static_cast<int>(reply->errorReceived()));
                    else
                        qCWarning(lcCoapClient, "Something went wrong, received a null reply");
            });
}

void QmlCoapMulticastClient::discover(const QString &host, int port, const QString &discoveryPath)
{
    QUrl url;
    url.setHost(host);
    url.setPort(port);

    QCoapResourceDiscoveryReply *discoverReply = QCoapClient::discover(url, discoveryPath);
    if (discoverReply) {
        connect(discoverReply, &QCoapResourceDiscoveryReply::discovered,
                this, &QmlCoapMulticastClient::onDiscovered);
    } else {
        qCWarning(lcCoapClient, "Discovery request failed.");
    }
}

void QmlCoapMulticastClient::discover(QtCoap::MulticastGroup group, int port,
                                      const QString &discoveryPath)
{
    QCoapResourceDiscoveryReply *discoverReply = QCoapClient::discover(group, port, discoveryPath);
    if (discoverReply) {
        connect(discoverReply, &QCoapResourceDiscoveryReply::discovered,
                this, &QmlCoapMulticastClient::onDiscovered);
    } else {
        qCWarning(lcCoapClient, "Discovery request failed.");
    }
}

void QmlCoapMulticastClient::onDiscovered(QCoapResourceDiscoveryReply *reply,
                                          const QList<QCoapResource> &resources)
{
    Q_UNUSED(reply)
    for (auto resource : resources)
        emit discovered(resource);
}