view rdf/PluginRDFIndexer.h @ 1376:d9511f9e04d7 dev/refactor-piper-related

Introduce some POD structs for describing an external server application and the desired libraries to load from it, and disambiguating between empty list request and invalid list request. This allows for overriding PiperVampPluginFactory behaviour for using a PluginScan to populate the list request.

/* -*- c-basic-offset: 4 indent-tabs-mode: nil -*-  vi:set ts=8 sts=4 sw=4: */

/*
    Sonic Visualiser
    An audio file viewer and annotation editor.
    Centre for Digital Music, Queen Mary, University of London.
    This file copyright 2008 QMUL.
   
    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License as
    published by the Free Software Foundation; either version 2 of the
    License, or (at your option) any later version.  See the file
    COPYING included with this distribution for more information.
*/

#ifndef _PLUGIN_RDF_INDEXER_H_
#define _PLUGIN_RDF_INDEXER_H_

#include <QString>
#include <QStringList>
#include <QMutex>
#include <map>
#include <set>

namespace Dataquay {
    class BasicStore;
}

class PluginRDFIndexer
{
public:
    static PluginRDFIndexer *getInstance();

    /**
     * Index all URLs obtained from index files defined in the current
     * settings.  In contrast to indexing URLs that are installed
     * locally alongside plugins, this is not done automatically
     * because it may incur significant processing and networking
     * effort.  It could be called from a background thread at
     * startup, for example.
     *
     * Note that this class has a single mutex, so other functions
     * will block if called from a different thread while this one is
     * running.
     */
    bool indexConfiguredURLs();

    bool indexURL(QString url); // in addition to "installed" URLs

    QString getURIForPluginId(QString pluginId);
    QString getIdForPluginURI(QString uri);

    QStringList getIndexedPluginIds();

    const Dataquay::BasicStore *getIndex();

    ~PluginRDFIndexer();

protected:
    PluginRDFIndexer();
    QMutex m_mutex;

    typedef std::map<QString, QString> StringMap;
    StringMap m_uriToIdMap;
    StringMap m_idToUriMap;

    void indexInstalledURLs();

    bool pullFile(QString path);
    bool pullURL(QString urlString);
    bool reindex();

    Dataquay::BasicStore *m_index;

    static PluginRDFIndexer *m_instance;
};

#endif