QGIS API Documentation 3.29.0-Master (8c80f25a4f)
qgsprocessingprovider.cpp
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1/***************************************************************************
2 qgsprocessingprovider.cpp
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
19#include "qgsapplication.h"
20#include "qgsvectorfilewriter.h"
21#include "qgsrasterfilewriter.h"
22#include "qgssettings.h"
23
25 : QObject( parent )
26{}
27
28
30{
31 qDeleteAll( mAlgorithms );
32}
33
35{
36 return QgsApplication::getThemeIcon( "/processingAlgorithm.svg" );
37}
38
40{
41 return QgsApplication::iconPath( QStringLiteral( "processingAlgorithm.svg" ) );
42}
43
44QgsProcessingProvider::Flags QgsProcessingProvider::flags() const
45{
46 return QgsProcessingProvider::Flags();
47}
48
50{
51 return QString();
52}
53
55{
56 return name();
57}
58
60{
61 return QString();
62}
63
65{
67}
68
70{
71 return QStringList();
72}
73
75{
76 qDeleteAll( mAlgorithms );
77 mAlgorithms.clear();
78 if ( isActive() )
79 {
81 emit algorithmsLoaded();
82 }
83}
84
85QList<const QgsProcessingAlgorithm *> QgsProcessingProvider::algorithms() const
86{
87 return mAlgorithms.values();
88}
89
91{
92 return mAlgorithms.value( name );
93}
94
96{
97 if ( !algorithm )
98 return false;
99
100 if ( mAlgorithms.contains( algorithm->name() ) )
101 {
102 QgsMessageLog::logMessage( tr( "Duplicate algorithm name %1 for provider %2" ).arg( algorithm->name(), id() ), QObject::tr( "Processing" ) );
103 return false;
104 }
105
106 // init the algorithm - this allows direct querying of the algorithm's parameters
107 // and outputs from the provider's copy
108 algorithm->initAlgorithm( QVariantMap() );
109
110 algorithm->setProvider( this );
111 mAlgorithms.insert( algorithm->name(), algorithm );
112 return true;
113}
114
116{
118}
119
121{
123}
124
125bool QgsProcessingProvider::isSupportedOutputValue( const QVariant &outputValue, const QgsProcessingDestinationParameter *parameter, QgsProcessingContext &context, QString &error ) const
126{
127 error.clear();
128 QString outputPath = QgsProcessingParameters::parameterAsOutputLayer( parameter, outputValue, context ).trimmed();
129
130 if ( outputPath.isEmpty() )
131 {
133 {
134 return true;
135 }
136 else
137 {
138 error = tr( "Missing parameter value %1" ).arg( parameter->description() );
139 return false;
140 }
141 }
142
145 {
146 if ( outputPath.startsWith( QLatin1String( "memory:" ) ) )
147 {
149 {
150 error = tr( "This algorithm only supports disk-based outputs" );
151 return false;
152 }
153 return true;
154 }
155
156 QString providerKey;
157 QString uri;
158 QString layerName;
159 QMap<QString, QVariant> options;
160 bool useWriter = false;
161 QString format;
162 QString extension;
163 QgsProcessingUtils::parseDestinationString( outputPath, providerKey, uri, layerName, format, options, useWriter, extension );
164
165 if ( providerKey != QLatin1String( "ogr" ) )
166 {
168 {
169 error = tr( "This algorithm only supports disk-based outputs" );
170 return false;
171 }
172 return true;
173 }
174
175 if ( !supportedOutputVectorLayerExtensions().contains( extension, Qt::CaseInsensitive ) )
176 {
177 error = tr( "“.%1” files are not supported as outputs for this algorithm" ).arg( extension );
178 return false;
179 }
180 return true;
181 }
182 else if ( parameter->type() == QgsProcessingParameterRasterDestination::typeName() )
183 {
184 const QFileInfo fi( outputPath );
185 const QString extension = fi.suffix();
186 if ( !supportedOutputRasterLayerExtensions().contains( extension, Qt::CaseInsensitive ) )
187 {
188 error = tr( "“.%1” files are not supported as outputs for this algorithm" ).arg( extension );
189 return false;
190 }
191 return true;
192 }
194 {
195 const QFileInfo fi( outputPath );
196 const QString extension = fi.completeSuffix();
197 if ( !supportedOutputPointCloudLayerExtensions().contains( extension, Qt::CaseInsensitive ) )
198 {
199 error = tr( "“.%1” files are not supported as outputs for this algorithm" ).arg( extension );
200 return false;
201 }
202 return true;
203 }
204 else
205 {
206 return true;
207 }
208}
209
211{
212 const QString userDefault = QgsProcessingUtils::defaultVectorExtension();
213
214 const QStringList supportedExtensions = supportedOutputVectorLayerExtensions();
215 if ( supportedExtensions.contains( userDefault, Qt::CaseInsensitive ) )
216 {
217 // user set default is supported by provider, use that
218 return userDefault;
219 }
220 else if ( !supportedExtensions.empty() )
221 {
222 return supportedExtensions.at( 0 );
223 }
224 else
225 {
226 // who knows? provider says it has no file support at all...
227 // let's say shp. even MapInfo supports shapefiles.
228 return hasGeometry ? QStringLiteral( "shp" ) : QStringLiteral( "dbf" );
229 }
230}
231
233{
234 const QString userDefault = QgsProcessingUtils::defaultRasterExtension();
235
236 const QStringList supportedExtensions = supportedOutputRasterLayerExtensions();
237 if ( supportedExtensions.contains( userDefault, Qt::CaseInsensitive ) )
238 {
239 // user set default is supported by provider, use that
240 return userDefault;
241 }
242 else if ( !supportedExtensions.empty() )
243 {
244 return supportedExtensions.at( 0 );
245 }
246 else
247 {
248 // who knows? provider says it has no file support at all...
249 return QStringLiteral( "tif" );
250 }
251}
252
254{
255 const QString userDefault = QgsProcessingUtils::defaultPointCloudExtension();
256
257 const QStringList supportedExtensions = supportedOutputPointCloudLayerExtensions();
258 if ( supportedExtensions.contains( userDefault, Qt::CaseInsensitive ) )
259 {
260 // user set default is supported by provider, use that
261 return userDefault;
262 }
263 else if ( !supportedExtensions.empty() )
264 {
265 return supportedExtensions.at( 0 );
266 }
267 else
268 {
269 // who knows? provider says it has no file support at all...
270 return QStringLiteral( "las" );
271 }
272}
273
275{
276 return true;
277}
static QIcon getThemeIcon(const QString &name, const QColor &fillColor=QColor(), const QColor &strokeColor=QColor())
Helper to get a theme icon.
static QString iconPath(const QString &iconFile)
Returns path to the desired icon file.
static void logMessage(const QString &message, const QString &tag=QString(), Qgis::MessageLevel level=Qgis::MessageLevel::Warning, bool notifyUser=true)
Adds a message to the log instance (and creates it if necessary).
Abstract base class for processing algorithms.
void setProvider(QgsProcessingProvider *provider)
Associates this algorithm with its provider.
virtual void initAlgorithm(const QVariantMap &configuration=QVariantMap())=0
Initializes the algorithm using the specified configuration.
virtual QString name() const =0
Returns the algorithm name, used for identifying the algorithm.
Contains information about the context in which a processing algorithm is executed.
Base class for all parameter definitions which represent file or layer destinations,...
QString description() const
Returns the description for the parameter.
virtual QString type() const =0
Unique parameter type name.
Flags flags() const
Returns any flags associated with the parameter.
static QString typeName()
Returns the type name for the parameter class.
static QString typeName()
Returns the type name for the parameter class.
static QString typeName()
Returns the type name for the parameter class.
static QString typeName()
Returns the type name for the parameter class.
static QString parameterAsOutputLayer(const QgsProcessingParameterDefinition *definition, const QVariantMap &parameters, QgsProcessingContext &context)
Evaluates the parameter with matching definition to a output layer destination.
virtual QIcon icon() const
Returns an icon for the provider.
virtual QString defaultVectorFileExtension(bool hasGeometry=true) const
Returns the default file extension to use for vector outputs created by the provider.
virtual QString helpId() const
Returns the provider help id string, used for creating QgsHelp urls for algorithms belong to this pro...
virtual bool isSupportedOutputValue(const QVariant &outputValue, const QgsProcessingDestinationParameter *parameter, QgsProcessingContext &context, QString &error) const
Returns true if the specified outputValue is of a supported file format for the given destination par...
virtual QStringList supportedOutputTableExtensions() const
Returns a list of the table (geometry-less vector layers) file extensions supported by this provider.
const QgsProcessingAlgorithm * algorithm(const QString &name) const
Returns the matching algorithm by name, or nullptr if no matching algorithm is contained by this prov...
virtual QString versionInfo() const
Returns a version information string for the provider, or an empty string if this is not applicable (...
virtual QStringList supportedOutputVectorLayerExtensions() const
Returns a list of the vector format file extensions supported by this provider.
virtual QString name() const =0
Returns the provider name, which is used to describe the provider within the GUI.
virtual QStringList supportedOutputRasterLayerExtensions() const
Returns a list of the raster format file extensions supported by this provider.
QgsProcessingProvider(QObject *parent=nullptr)
Constructor for QgsProcessingProvider.
virtual bool isActive() const
Returns true if the provider is active and able to run algorithms.
virtual QStringList supportedOutputPointCloudLayerExtensions() const
Returns a list of the point cloud format file extensions supported by this provider.
virtual QString defaultRasterFileExtension() const
Returns the default file extension to use for raster outputs created by the provider.
void algorithmsLoaded()
Emitted when the provider has loaded (or refreshed) its list of available algorithms.
virtual QString svgIconPath() const
Returns a path to an SVG version of the provider's icon.
virtual void loadAlgorithms()=0
Loads all algorithms belonging to this provider.
void refreshAlgorithms()
Refreshes the algorithms available from the provider, causing it to re-populate with all associated a...
virtual QString longName() const
Returns the longer version of the provider name, which can include extra details such as version numb...
virtual bool supportsNonFileBasedOutput() const
Returns true if the provider supports non-file based outputs (such as memory layers or direct databas...
virtual Flags flags() const
Returns the flags indicating how and when the provider operates and should be exposed to users.
virtual QString defaultPointCloudFileExtension() const
Returns the default file extension to use for point cloud outputs created by the provider.
bool addAlgorithm(QgsProcessingAlgorithm *algorithm)
Adds an algorithm to the provider.
QList< const QgsProcessingAlgorithm * > algorithms() const
Returns a list of algorithms supplied by this provider.
static QString defaultVectorExtension()
Returns the default vector extension to use, in the absence of all other constraints (e....
static QString defaultRasterExtension()
Returns the default raster extension to use, in the absence of all other constraints (e....
static QString defaultPointCloudExtension()
Returns the default point cloud extension to use, in the absence of all other constraints (e....
static QStringList supportedFormatExtensions(RasterFormatOptions options=SortRecommended)
Returns a list of file extensions for supported formats.
static QStringList supportedFormatExtensions(VectorFormatOptions options=SortRecommended)
Returns a list of file extensions for supported formats, e.g "shp", "gpkg".
As part of the API refactoring and improvements which landed in the Processing API was substantially reworked from the x version This was done in order to allow much of the underlying Processing framework to be ported into allowing algorithms to be written in pure substantial changes are required in order to port existing x Processing algorithms for QGIS x The most significant changes are outlined not GeoAlgorithm For algorithms which operate on features one by consider subclassing the QgsProcessingFeatureBasedAlgorithm class This class allows much of the boilerplate code for looping over features from a vector layer to be bypassed and instead requires implementation of a processFeature method Ensure that your algorithm(or algorithm 's parent class) implements the new pure virtual createInstance(self) call
#define SIP_TRANSFERTHIS
Definition: qgis_sip.h:53