QGIS API Documentation  3.2.0-Bonn (bc43194)
qgsprocessingalgorithm.h
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1 /***************************************************************************
2  qgsprocessingalgorithm.h
3  ------------------------
4  begin : December 2016
5  copyright : (C) 2016 by Nyall Dawson
6  email : nyall dot dawson at gmail dot com
7  ***************************************************************************/
8 
9 /***************************************************************************
10  * *
11  * This program is free software; you can redistribute it and/or modify *
12  * it under the terms of the GNU General Public License as published by *
13  * the Free Software Foundation; either version 2 of the License, or *
14  * (at your option) any later version. *
15  * *
16  ***************************************************************************/
17 
18 #ifndef QGSPROCESSINGALGORITHM_H
19 #define QGSPROCESSINGALGORITHM_H
20 
21 #include "qgis_core.h"
22 #include "qgis.h"
23 #include "qgsprocessingparameters.h"
24 #include "qgsprocessingoutputs.h"
25 #include "qgsprocessingcontext.h"
26 #include "qgsfeaturesource.h"
27 #include "qgsprocessingutils.h"
28 #include <QString>
29 #include <QVariant>
30 #include <QIcon>
31 
32 class QgsProcessingProvider;
33 class QgsProcessingFeedback;
34 class QgsFeatureSink;
35 class QgsProcessingFeedback;
36 class QgsProcessingModelAlgorithm;
37 class QgsProcessingAlgorithmConfigurationWidget;
38 
39 #ifdef SIP_RUN
40 % ModuleHeaderCode
41 #include <qgsprocessingmodelalgorithm.h>
42 % End
43 #endif
44 
51 class CORE_EXPORT QgsProcessingAlgorithm
52 {
53 
54 #ifdef SIP_RUN
55  SIP_CONVERT_TO_SUBCLASS_CODE
56  if ( dynamic_cast< QgsProcessingModelAlgorithm * >( sipCpp ) != NULL )
57  sipType = sipType_QgsProcessingModelAlgorithm;
58  else if ( dynamic_cast< QgsProcessingFeatureBasedAlgorithm * >( sipCpp ) != NULL )
59  sipType = sipType_QgsProcessingFeatureBasedAlgorithm;
60  else
61  sipType = sipType_QgsProcessingAlgorithm;
62  SIP_END
63 #endif
64 
65  public:
66 
68  enum Flag
69  {
70  FlagHideFromToolbox = 1 << 1,
71  FlagHideFromModeler = 1 << 2,
72  FlagSupportsBatch = 1 << 3,
73  FlagCanCancel = 1 << 4,
74  FlagRequiresMatchingCrs = 1 << 5,
75  FlagNoThreading = 1 << 6,
76  FlagDisplayNameIsLiteral = 1 << 7,
77  FlagDeprecated = FlagHideFromToolbox | FlagHideFromModeler,
78  };
79  Q_DECLARE_FLAGS( Flags, Flag )
80 
81 
88  QgsProcessingAlgorithm() = default;
89 
90  virtual ~QgsProcessingAlgorithm();
91 
93  QgsProcessingAlgorithm( const QgsProcessingAlgorithm &other ) = delete;
95  QgsProcessingAlgorithm &operator=( const QgsProcessingAlgorithm &other ) = delete;
96 
97  /*
98  * IMPORTANT: While it seems like /Factory/ would be the correct annotation here, that's not
99  * the case.
100  * As per Phil Thomson's advice on https://www.riverbankcomputing.com/pipermail/pyqt/2017-July/039450.html:
101  *
102  * "
103  * /Factory/ is used when the instance returned is guaranteed to be new to Python.
104  * In this case it isn't because it has already been seen when being returned by createInstance()
105  * (However for a different sub-class implemented in C++ then it would be the first time it was seen
106  * by Python so the /Factory/ on create() would be correct.)
107  *
108  * You might try using /TransferBack/ on create() instead - that might be the best compromise.
109  * "
110  */
111 
126  QgsProcessingAlgorithm *create( const QVariantMap &configuration = QVariantMap() ) const SIP_TRANSFERBACK;
127 
137  virtual QString name() const = 0;
138 
145  QString id() const;
146 
157  virtual QString displayName() const = 0;
158 
164  virtual QString shortDescription() const;
165 
170  virtual QStringList tags() const { return QStringList(); }
171 
178  virtual QString shortHelpString() const;
179 
186  virtual QString helpString() const;
187 
193  virtual QString helpUrl() const;
194 
199  virtual QIcon icon() const;
200 
205  virtual QString svgIconPath() const;
206 
213  virtual QString group() const { return QString(); }
214 
222  virtual QString groupId() const { return QString(); }
223 
228  virtual Flags flags() const;
229 
236  virtual bool canExecute( QString *errorMessage SIP_OUT = nullptr ) const;
237 
245  virtual bool checkParameterValues( const QVariantMap &parameters,
246  QgsProcessingContext &context, QString *message SIP_OUT = nullptr ) const;
247 
255  virtual QVariantMap preprocessParameters( const QVariantMap &parameters );
256 
260  QgsProcessingProvider *provider() const;
261 
268  QgsProcessingParameterDefinitions parameterDefinitions() const { return mParameters; }
269 
275  const QgsProcessingParameterDefinition *parameterDefinition( const QString &name ) const;
276 
281  int countVisibleParameters() const;
282 
288  QgsProcessingParameterDefinitions destinationParameterDefinitions() const;
289 
295  QgsProcessingOutputDefinitions outputDefinitions() const { return mOutputs; }
296 
302  const QgsProcessingOutputDefinition *outputDefinition( const QString &name ) const;
303 
307  bool hasHtmlOutputs() const;
308 
326  QVariantMap run( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback, bool *ok SIP_OUT = nullptr, const QVariantMap &configuration = QVariantMap() ) const;
327 
338  bool prepare( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback );
339 
351  QVariantMap runPrepared( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) SIP_THROW( QgsProcessingException );
352 
361  QVariantMap postProcess( QgsProcessingContext &context, QgsProcessingFeedback *feedback );
362 
369  virtual QWidget *createCustomParametersWidget( QWidget *parent = nullptr ) const SIP_FACTORY;
370 
377  QgsExpressionContext createExpressionContext( const QVariantMap &parameters,
378  QgsProcessingContext &context, QgsProcessingFeatureSource *source = nullptr ) const;
379 
386  virtual bool validateInputCrs( const QVariantMap &parameters,
387  QgsProcessingContext &context ) const;
388 
396  virtual QString asPythonCommand( const QVariantMap &parameters, QgsProcessingContext &context ) const;
397 
401  void setProvider( QgsProcessingProvider *provider );
402 
403  protected:
404 
410  virtual QgsProcessingAlgorithm *createInstance() const = 0 SIP_FACTORY;
411 
430  virtual void initAlgorithm( const QVariantMap &configuration = QVariantMap() ) = 0;
431 
449  bool addParameter( QgsProcessingParameterDefinition *parameterDefinition SIP_TRANSFER, bool createOutput = true );
450 
455  void removeParameter( const QString &name );
456 
470  bool addOutput( QgsProcessingOutputDefinition *outputDefinition SIP_TRANSFER );
471 
502  virtual bool prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) SIP_THROW( QgsProcessingException ) SIP_VIRTUALERRORHANDLER( processing_exception_handler );
503 
534  virtual QVariantMap processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) SIP_THROW( QgsProcessingException ) = 0 SIP_VIRTUALERRORHANDLER( processing_exception_handler );
535 
563  virtual QVariantMap postProcessAlgorithm( QgsProcessingContext &context, QgsProcessingFeedback *feedback ) SIP_THROW( QgsProcessingException ) SIP_VIRTUALERRORHANDLER( processing_exception_handler );
564 
568  QString parameterAsString( const QVariantMap &parameters, const QString &name, const QgsProcessingContext &context ) const;
569 
573  QString parameterAsExpression( const QVariantMap &parameters, const QString &name, const QgsProcessingContext &context ) const;
574 
578  double parameterAsDouble( const QVariantMap &parameters, const QString &name, const QgsProcessingContext &context ) const;
579 
583  int parameterAsInt( const QVariantMap &parameters, const QString &name, const QgsProcessingContext &context ) const;
584 
588  int parameterAsEnum( const QVariantMap &parameters, const QString &name, const QgsProcessingContext &context ) const;
589 
593  QList<int> parameterAsEnums( const QVariantMap &parameters, const QString &name, const QgsProcessingContext &context ) const;
594 
598  bool parameterAsBool( const QVariantMap &parameters, const QString &name, const QgsProcessingContext &context ) const;
599 
614  QgsFeatureSink *parameterAsSink( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context, QString &destinationIdentifier SIP_OUT,
615  const QgsFields &fields, QgsWkbTypes::Type geometryType = QgsWkbTypes::NoGeometry, const QgsCoordinateReferenceSystem &crs = QgsCoordinateReferenceSystem() ) const SIP_FACTORY;
616 
625  QgsProcessingFeatureSource *parameterAsSource( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const SIP_FACTORY;
626 
639  QString parameterAsCompatibleSourceLayerPath( const QVariantMap &parameters, const QString &name,
640  QgsProcessingContext &context, const QStringList &compatibleFormats, const QString &preferredFormat = QString( "shp" ), QgsProcessingFeedback *feedback = nullptr );
641 
649  QgsMapLayer *parameterAsLayer( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
650 
658  QgsRasterLayer *parameterAsRasterLayer( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
659 
663  QString parameterAsOutputLayer( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
664 
668  QString parameterAsFileOutput( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
669 
677  QgsVectorLayer *parameterAsVectorLayer( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
678 
682  QgsCoordinateReferenceSystem parameterAsCrs( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
683 
692  QgsRectangle parameterAsExtent( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context,
693  const QgsCoordinateReferenceSystem &crs = QgsCoordinateReferenceSystem() ) const;
694 
705  QgsGeometry parameterAsExtentGeometry( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context,
706  const QgsCoordinateReferenceSystem &crs = QgsCoordinateReferenceSystem() );
707 
713  QgsCoordinateReferenceSystem parameterAsExtentCrs( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context );
714 
723  QgsPointXY parameterAsPoint( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context,
724  const QgsCoordinateReferenceSystem &crs = QgsCoordinateReferenceSystem() ) const;
725 
731  QgsCoordinateReferenceSystem parameterAsPointCrs( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context );
732 
736  QString parameterAsFile( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
737 
742  QVariantList parameterAsMatrix( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
743 
747  QList< QgsMapLayer *> parameterAsLayerList( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
748 
752  QList<double> parameterAsRange( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
753 
757  QStringList parameterAsFields( const QVariantMap &parameters, const QString &name, QgsProcessingContext &context ) const;
758 
771  static QString invalidSourceError( const QVariantMap &parameters, const QString &name );
772 
785  static QString invalidRasterError( const QVariantMap &parameters, const QString &name );
786 
799  static QString invalidSinkError( const QVariantMap &parameters, const QString &name );
800 
801  private:
802 
803  QgsProcessingProvider *mProvider = nullptr;
804  QgsProcessingParameterDefinitions mParameters;
805  QgsProcessingOutputDefinitions mOutputs;
806  bool mHasPrepared = false;
807  bool mHasExecuted = false;
808  bool mHasPostProcessed = false;
809  std::unique_ptr< QgsProcessingContext > mLocalContext;
810 
811  bool createAutoOutputForParameter( QgsProcessingParameterDefinition *parameter );
812 
813  friend class QgsProcessingProvider;
814  friend class TestQgsProcessing;
815  friend class QgsProcessingModelAlgorithm;
816 
817 #ifdef SIP_RUN
818  QgsProcessingAlgorithm( const QgsProcessingAlgorithm &other );
819 #endif
820 
821 };
822 Q_DECLARE_OPERATORS_FOR_FLAGS( QgsProcessingAlgorithm::Flags )
823 
824 
825 
826 
849 class CORE_EXPORT QgsProcessingFeatureBasedAlgorithm : public QgsProcessingAlgorithm
850 {
851  public:
852 
856  QgsProcessingFeatureBasedAlgorithm() = default;
857 
858  protected:
859 
860  void initAlgorithm( const QVariantMap &configuration = QVariantMap() ) override;
861 
867  virtual QString outputName() const = 0;
868 
874  virtual QList<int> inputLayerTypes() const;
875 
880  virtual QgsProcessing::SourceType outputLayerType() const;
881 
885  virtual QgsProcessingFeatureSource::Flag sourceFlags() const;
886 
894  virtual QgsWkbTypes::Type outputWkbType( QgsWkbTypes::Type inputWkbType ) const;
895 
906  virtual QgsFields outputFields( const QgsFields &inputFields ) const;
907 
916  virtual QgsCoordinateReferenceSystem outputCrs( const QgsCoordinateReferenceSystem &inputCrs ) const;
917 
923  virtual void initParameters( const QVariantMap &configuration = QVariantMap() );
924 
929  QgsCoordinateReferenceSystem sourceCrs() const;
930 
954  virtual QgsFeatureList processFeature( const QgsFeature &feature, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) SIP_THROW( QgsProcessingException ) = 0 SIP_VIRTUALERRORHANDLER( processing_exception_handler );
955 
956  QVariantMap processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback ) override SIP_THROW( QgsProcessingException );
957 
962  virtual QgsFeatureRequest request() const;
963 
964  private:
965 
966  std::unique_ptr< QgsProcessingFeatureSource > mSource;
967 
968 };
969 
970 // clazy:excludeall=qstring-allocations
971 
972 #endif // QGSPROCESSINGALGORITHM_H
973 
974 
SIP_VIRTUALERRORHANDLER
#define SIP_VIRTUALERRORHANDLER(name)
Definition: qgis_sip.h:170
QgsProcessingParameterDefinitions
QList< const QgsProcessingParameterDefinition *> QgsProcessingParameterDefinitions
List of processing parameters.
Definition: qgsprocessingparameters.h:530
QgsRectangle
A rectangle specified with double values.
Definition: qgsrectangle.h:40
QgsMapLayer
Base class for all map layer types.
Definition: qgsmaplayer.h:61
QgsProcessingFeedback
Base class for providing feedback from a processing algorithm.
Definition: qgsprocessingfeedback.h:35
QgsProcessingAlgorithm::parameterDefinitions
QgsProcessingParameterDefinitions parameterDefinitions() const
Returns an ordered list of parameter definitions utilized by the algorithm.
Definition: qgsprocessingalgorithm.h:268
QgsRasterLayer
This class provides qgis with the ability to render raster datasets onto the mapcanvas.
Definition: qgsrasterlayer.h:139
QgsFeatureList
QList< QgsFeature > QgsFeatureList
Definition: qgsfeature.h:549
QgsProcessingAlgorithm::group
virtual QString group() const
Returns the name of the group this algorithm belongs to.
Definition: qgsprocessingalgorithm.h:213
QgsPointXY
A class to represent a 2D point.
Definition: qgspointxy.h:43
QgsFeatureSink
An interface for objects which accept features via addFeature(s) methods.
Definition: qgsfeaturesink.h:33
QgsProcessingFeatureSource
QgsFeatureSource subclass which proxies methods to an underlying QgsFeatureSource, modifying results according to the settings in a QgsProcessingContext.
Definition: qgsprocessingutils.h:291
QgsFields
Container of fields for a vector layer.
Definition: qgsfields.h:42
QgsGeometry
A geometry is the spatial representation of a feature.
Definition: qgsgeometry.h:104
QgsProcessingProvider
Abstract base class for processing providers.
Definition: qgsprocessingprovider.h:34
QgsFeature
The feature class encapsulates a single feature including its id, geometry and a list of field/values...
Definition: qgsfeature.h:62
SIP_TRANSFERBACK
#define SIP_TRANSFERBACK
Definition: qgis_sip.h:41
QgsProcessingAlgorithm
Abstract base class for processing algorithms.
Definition: qgsprocessingalgorithm.h:51
QgsWkbTypes::Type
Type
The WKB type describes the number of dimensions a geometry has.
Definition: qgswkbtypes.h:67
QgsExpressionContext
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
Definition: qgsexpressioncontext.h:375
SIP_TRANSFER
#define SIP_TRANSFER
Definition: qgis_sip.h:36
QgsFeatureRequest
This class wraps a request for features to a vector layer (or directly its vector data provider)...
Definition: qgsfeaturerequest.h:72
QgsProcessingException
Custom exception class for processing related exceptions.
Definition: qgsexception.h:82
SIP_END
#define SIP_END
Definition: qgis_sip.h:182
SIP_FACTORY
#define SIP_FACTORY
Definition: qgis_sip.h:69
QgsProcessingFeatureSource::Flag
Flag
Flags controlling how QgsProcessingFeatureSource fetches features.
Definition: qgsprocessingutils.h:296
QgsProcessingAlgorithm::outputDefinitions
QgsProcessingOutputDefinitions outputDefinitions() const
Returns an ordered list of output definitions utilized by the algorithm.
Definition: qgsprocessingalgorithm.h:295
QgsProcessingOutputDefinition
Base class for the definition of processing outputs.
Definition: qgsprocessingoutputs.h:41
QgsProcessingOutputDefinitions
QList< const QgsProcessingOutputDefinition *> QgsProcessingOutputDefinitions
List of processing parameters.
Definition: qgsprocessingoutputs.h:122
QgsProcessingAlgorithmConfigurationWidget
A configuration widget for processing algorithms allows providing additional configuration options di...
Definition: qgsprocessingalgorithmconfigurationwidget.h:38
SIP_OUT
#define SIP_OUT
Definition: qgis_sip.h:51
QgsCoordinateReferenceSystem
This class represents a coordinate reference system (CRS).
Definition: qgscoordinatereferencesystem.h:189
QgsProcessingParameterDefinition
Base class for the definition of processing parameters.
Definition: qgsprocessingparameters.h:201
QgsProcessingAlgorithm::Flag
Flag
Flags indicating how and when an algorithm operates and should be exposed to users.
Definition: qgsprocessingalgorithm.h:68
SIP_CONVERT_TO_SUBCLASS_CODE
#define SIP_CONVERT_TO_SUBCLASS_CODE(code)
Definition: qgis_sip.h:165
QgsProcessing::SourceType
SourceType
Data source types enum.
Definition: qgsprocessing.h:44
SIP_THROW
#define SIP_THROW(name)
Definition: qgis_sip.h:177
QgsProcessingAlgorithm::groupId
virtual QString groupId() const
Returns the unique ID of the group this algorithm belongs to.
Definition: qgsprocessingalgorithm.h:222
QgsProcessingFeatureBasedAlgorithm
An abstract QgsProcessingAlgorithm base class for processing algorithms which operate "feature-by-fea...
Definition: qgsprocessingalgorithm.h:849
QgsVectorLayer
Represents a vector layer which manages a vector based data sets.
Definition: qgsvectorlayer.h:353
QgsProcessingContext
Contains information about the context in which a processing algorithm is executed.
Definition: qgsprocessingcontext.h:42
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