qgsprocessingutils.h

Go to the documentation of this file.

/***************************************************************************
                         qgsprocessingutils.h
                         ------------------------
    begin                : April 2017
    copyright            : (C) 2017 by Nyall Dawson
    email                : nyall dot dawson at gmail dot 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 QGSPROCESSINGUTILS_H
#define QGSPROCESSINGUTILS_H

#include "qgis_core.h"

#include "qgsrasterlayer.h"
#include "qgsvectorlayer.h"
#include "qgsmessagelog.h"
#include "qgsspatialindex.h"
#include "qgsprocessing.h"

class QgsProject;
class QgsProcessingContext;
class QgsMapLayerStore;
class QgsProcessingFeedback;
class QgsProcessingFeatureSource;

#include <QString>
#include <QVariant>

class CORE_EXPORT QgsProcessingUtils
{

  public:

    static QList< QgsRasterLayer * > compatibleRasterLayers( QgsProject *project, bool sort = true );

    static QList< QgsVectorLayer * > compatibleVectorLayers( QgsProject *project,
        const QList< int > &sourceTypes = QList< int >(),
        bool sort = true );

    static QList< QgsMapLayer * > compatibleLayers( QgsProject *project, bool sort = true );

    static QgsMapLayer *mapLayerFromString( const QString &string, QgsProcessingContext &context, bool allowLoadingNewLayers = true );

    static QgsProcessingFeatureSource *variantToSource( const QVariant &value, QgsProcessingContext &context, const QVariant &fallbackValue = QVariant() ) SIP_FACTORY;

    static QString normalizeLayerSource( const QString &source );

    static QString stringToPythonLiteral( const QString &string );

#ifndef SIP_RUN
    static QgsFeatureSink *createFeatureSink(
      QString &destination,
      QgsProcessingContext &context,
      const QgsFields &fields,
      QgsWkbTypes::Type geometryType,
      const QgsCoordinateReferenceSystem &crs,
      const QVariantMap &createOptions = QVariantMap() ) SIP_FACTORY;
#endif

    static void createFeatureSinkPython( QgsFeatureSink **sink SIP_OUT SIP_TRANSFERBACK, QString &destination SIP_INOUT, QgsProcessingContext &context, const QgsFields &fields, QgsWkbTypes::Type geometryType, const QgsCoordinateReferenceSystem &crs, const QVariantMap &createOptions = QVariantMap() ) SIP_THROW( QgsProcessingException ) SIP_PYNAME( createFeatureSink );

    static QgsRectangle combineLayerExtents( const QList<QgsMapLayer *> &layers, const QgsCoordinateReferenceSystem &crs = QgsCoordinateReferenceSystem() );

    static QVariant generateIteratingDestination( const QVariant &input, const QVariant &id, QgsProcessingContext &context );

    static QString tempFolder();

    static QString generateTempFilename( const QString &basename );

    static QString formatHelpMapAsHtml( const QVariantMap &map, const QgsProcessingAlgorithm *algorithm );

    static QString convertToCompatibleFormat( const QgsVectorLayer *layer,
        bool selectedFeaturesOnly,
        const QString &baseName,
        const QStringList &compatibleFormats,
        const QString &preferredFormat,
        QgsProcessingContext &context,
        QgsProcessingFeedback *feedback );

    static QgsFields combineFields( const QgsFields &fieldsA, const QgsFields &fieldsB );

    static QList<int> fieldNamesToIndices( const QStringList &fieldNames, const QgsFields &fields );

    static QgsFields indicesToFields( const QList<int> &indices, const QgsFields &fields );

  private:

    static bool canUseLayer( const QgsRasterLayer *layer );
    static bool canUseLayer( const QgsVectorLayer *layer,
                             const QList< int > &sourceTypes = QList< int >() );

    static QgsMapLayer *mapLayerFromStore( const QString &string, QgsMapLayerStore *store );

    static QgsMapLayer *loadMapLayerFromString( const QString &string );

    static void parseDestinationString( QString &destination, QString &providerKey, QString &uri, QString &layerName, QString &format, QMap<QString, QVariant> &options, bool &useWriter );

    friend class TestQgsProcessing;

};

class CORE_EXPORT QgsProcessingFeatureSource : public QgsFeatureSource
{
  public:

    enum Flag
    {
      FlagSkipGeometryValidityChecks = 1 << 1, 
    };
    Q_DECLARE_FLAGS( Flags, Flag )

    
    QgsProcessingFeatureSource( QgsFeatureSource *originalSource, const QgsProcessingContext &context, bool ownsOriginalSource = false );

    ~QgsProcessingFeatureSource() override;

    QgsFeatureIterator getFeatures( const QgsFeatureRequest &request, Flags flags ) const;

    QgsFeatureIterator getFeatures( const QgsFeatureRequest &request = QgsFeatureRequest() ) const override;
    QgsCoordinateReferenceSystem sourceCrs() const override;
    QgsFields fields() const override;
    QgsWkbTypes::Type wkbType() const override;
    long featureCount() const override;
    QString sourceName() const override;
    QSet<QVariant> uniqueValues( int fieldIndex, int limit = -1 ) const override;
    QVariant minimumValue( int fieldIndex ) const override;
    QVariant maximumValue( int fieldIndex ) const override;
    QgsRectangle sourceExtent() const override;
    QgsFeatureIds allFeatureIds() const override;

    QgsExpressionContextScope *createExpressionContextScope() const SIP_FACTORY;

  private:

    QgsFeatureSource *mSource = nullptr;
    bool mOwnsSource = false;
    QgsFeatureRequest::InvalidGeometryCheck mInvalidGeometryCheck = QgsFeatureRequest::GeometryNoCheck;
    std::function< void( const QgsFeature & ) > mInvalidGeometryCallback;
    std::function< void( const QgsFeature & ) > mTransformErrorCallback;

};

#ifndef SIP_RUN

class CORE_EXPORT QgsProcessingFeatureSink : public QgsProxyFeatureSink
{
  public:


    QgsProcessingFeatureSink( QgsFeatureSink *originalSink, const QString &sinkName, QgsProcessingContext &context, bool ownsOriginalSink = false );
    ~QgsProcessingFeatureSink() override;
    bool addFeature( QgsFeature &feature, QgsFeatureSink::Flags flags = nullptr ) override;
    bool addFeatures( QgsFeatureList &features, QgsFeatureSink::Flags flags = nullptr ) override;
    bool addFeatures( QgsFeatureIterator &iterator, QgsFeatureSink::Flags flags = nullptr ) override;

  private:

    QgsProcessingContext &mContext;
    QString mSinkName;
    bool mOwnsSink = false;

};
#endif

#endif // QGSPROCESSINGUTILS_H