HttpDownloader.hpp Example File

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    #ifndef HTTPDOWNLOADER_HPP
    #define HTTPDOWNLOADER_HPP

    #include "AuthenticationDialogController.hpp"
    #include "MessageBoxController.hpp"

    #include <QtCore/QUrl>
    #include <QtNetwork/QNetworkAccessManager>

    class QFile;

    /**
     * The HttpDownloader class contains all the logic to download URLs from
     * the network and store them in a local file.
     */
    class HttpDownloader : public QObject
    {
        Q_OBJECT

        // Makes available to the UI whether the next download can be started
        Q_PROPERTY(bool startDownloadPossible READ startDownloadPossible NOTIFY startDownloadPossibleChanged)

        // Makes the status text available to the UI
        Q_PROPERTY(QString statusText READ statusText NOTIFY statusTextChanged)
    public:
        explicit HttpDownloader(QObject *parent = 0);
        ~HttpDownloader();
        // This method is executed when the user clicks the 'Download' button in the UI
        Q_INVOKABLE void startDownload(const QString &url);

        // The accessor methods for the properties
        bool startDownloadPossible() const;
        QString statusText() const;
        // The accessor methods for the dialog controllers
        MessageBoxController *messageBoxController() const;
        AuthenticationDialogController *authenticationDialogController() const;

    Q_SIGNALS:
        // The change notification signals of the properties
        void startDownloadPossibleChanged();
        void statusTextChanged();
    private Q_SLOTS:
        // This method is called whenever a download job has finished
        void httpFinished();

        // This method is called whenever a download job received new data
        void httpReadyRead();

        // This method is called if authentication is required to continue the download
        void slotAuthenticationRequired(QNetworkReply*, QAuthenticator *authenticator);

        // This method is called if a error occurred during the initial SSL handshake
        void sslErrors(QNetworkReply*, const QList<QSslError> &errors);

    private:
        // A helper method to change the 'startDownloadPossible' property
        void setStartDownloadPossible(bool possible);

        // Starts a new download job
        void startRequest();

        // A flag to mark whether a new download can be started
        bool m_startDownloadPossible;

        // The status text for the current download
        QString m_statusText;

        // The source URL of the current download
        QUrl m_url;

        // The target file of the current download
        QFile *m_file;
        // The network access manager
        QNetworkAccessManager m_qnam;
        // The network reply that represents the current download
        QNetworkReply *m_reply;

        // The file name of the target file
        QString m_fileName;

        // The dialog controllers
        MessageBoxController m_messageBoxController;
        AuthenticationDialogController m_authenticationDialogController;
    };

    #endif