qgsprovidermetadata.h

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/***************************************************************************
                    qgsprovidermetadata.h  -  Metadata class for
                    describing a data provider.
                             -------------------
    begin                : Sat Jan 10 2004
    copyright            : (C) 2004 by Gary E.Sherman
    email                : sherman at mrcc.com
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/

#ifndef QGSPROVIDERMETADATA_H
#define QGSPROVIDERMETADATA_H


#include <QString>
#include "qgis.h"
#include "qgsdataprovider.h"
#include "qgis_core.h"
#include <functional>

class CORE_EXPORT QgsProviderMetadata
{
  public:

    SIP_SKIP typedef std::function < QgsDataProvider*( const QString &, const QgsDataProvider::ProviderOptions & ) > CreateDataProviderFunction;

    QgsProviderMetadata( const QString &_key, const QString &_description, const QString &_library );

#ifndef SIP_RUN
    QgsProviderMetadata( const QString &key, const QString &description, const QgsProviderMetadata::CreateDataProviderFunction &createFunc );
#else
    QgsProviderMetadata( const QString &key, const QString &description, SIP_PYCALLABLE / AllowNone / );
    % MethodCode

    // Make sure the callable doesn't get garbage collected, this is needed because refcount for a2 is 0
    // and the creation function pointer is passed to the metadata and it needs to be kept in memory.
    Py_INCREF( a2 );

    Py_BEGIN_ALLOW_THREADS

    sipCpp = new QgsProviderMetadata( *a0, *a1, [a2]( const QString &dataSource, const QgsDataProvider::ProviderOptions &providerOptions ) -> QgsDataProvider*
    {
      QgsDataProvider *provider;
      provider = nullptr;
      PyObject *sipResObj;
      SIP_BLOCK_THREADS

      sipResObj = sipCallMethod( nullptr, a2, "DD", new QString( dataSource ), sipType_QString, nullptr, new QgsDataProvider::ProviderOptions( providerOptions ), sipType_QgsDataProvider_ProviderOptions, NULL );

      if ( sipResObj )
      {
        if ( sipCanConvertToType( sipResObj, sipType_QgsDataProvider, SIP_NOT_NONE ) )
        {
          int state0;
          int sipIsErr = 0;
          provider = reinterpret_cast<QgsDataProvider *>( sipConvertToType( sipResObj, sipType_QgsDataProvider, nullptr, SIP_NOT_NONE, &state0, &sipIsErr ) );
          if ( sipIsErr != 0 )
          {
            sipReleaseType( provider, sipType_QgsDataProvider, state0 );
            provider = nullptr;
          }
        }
      }
      SIP_UNBLOCK_THREADS
      return provider;
    } );

    Py_END_ALLOW_THREADS

    % End
#endif

    QString key() const;

    QString description() const;

    QString library() const;

    SIP_SKIP CreateDataProviderFunction createFunction() const;

  private:

    QString key_;

    QString description_;

    QString library_;

    CreateDataProviderFunction mCreateFunc = nullptr;

};

#endif //QGSPROVIDERMETADATA_H