QGIS API Documentation  3.2.0-Bonn (bc43194)
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 
18 #include "qgsprocessingprovider.h"
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 
45 {
46  return id();
47 }
48 
50 {
51  return name();
52 }
53 
55 {
57 }
58 
60 {
61  qDeleteAll( mAlgorithms );
62  mAlgorithms.clear();
63  if ( isActive() )
64  {
66  emit algorithmsLoaded();
67  }
68 }
69 
70 QList<const QgsProcessingAlgorithm *> QgsProcessingProvider::algorithms() const
71 {
72  return mAlgorithms.values();
73 }
74 
76 {
77  return mAlgorithms.value( name );
78 }
79 
81 {
82  if ( !algorithm )
83  return false;
84 
85  if ( mAlgorithms.contains( algorithm->name() ) )
86  {
87  QgsMessageLog::logMessage( tr( "Duplicate algorithm name %1 for provider %2" ).arg( algorithm->name(), id() ), QObject::tr( "Processing" ) );
88  return false;
89  }
90 
91  // init the algorithm - this allows direct querying of the algorithm's parameters
92  // and outputs from the provider's copy
93  algorithm->initAlgorithm( QVariantMap() );
94 
95  algorithm->setProvider( this );
96  mAlgorithms.insert( algorithm->name(), algorithm );
97  return true;
98 }
99 
101 {
103 }
104 
105 QString QgsProcessingProvider::defaultVectorFileExtension( bool hasGeometry ) const
106 {
107  QgsSettings settings;
108  const QString defaultExtension = hasGeometry ? QStringLiteral( "shp" ) : QStringLiteral( "dbf" );
109  const QString userDefault = settings.value( QStringLiteral( "Processing/DefaultOutputVectorLayerExt" ), defaultExtension, QgsSettings::Core ).toString();
110 
111  const QStringList supportedExtensions = supportedOutputVectorLayerExtensions();
112  if ( supportedExtensions.contains( userDefault, Qt::CaseInsensitive ) )
113  {
114  // user set default is supported by provider, use that
115  return userDefault;
116  }
117  else if ( !supportedExtensions.empty() )
118  {
119  return supportedExtensions.at( 0 );
120  }
121  else
122  {
123  // who knows? provider says it has no file support at all...
124  // let's say shp. even MapInfo supports shapefiles.
125  return defaultExtension;
126  }
127 }
128 
130 {
131  QgsSettings settings;
132  const QString defaultExtension = QStringLiteral( "tif" );
133  const QString userDefault = settings.value( QStringLiteral( "Processing/DefaultOutputRasterLayerExt" ), defaultExtension, QgsSettings::Core ).toString();
134 
135  const QStringList supportedExtensions = supportedOutputRasterLayerExtensions();
136  if ( supportedExtensions.contains( userDefault, Qt::CaseInsensitive ) )
137  {
138  // user set default is supported by provider, use that
139  return userDefault;
140  }
141  else if ( !supportedExtensions.empty() )
142  {
143  return supportedExtensions.at( 0 );
144  }
145  else
146  {
147  // who knows? provider says it has no file support at all...
148  return defaultExtension;
149  }
150 }
151 
153 {
154  return true;
155 }
void setProvider(QgsProcessingProvider *provider)
Associates this algorithm with its provider.
#define SIP_TRANSFERTHIS
Definition: qgis_sip.h:46
virtual QString name() const =0
Returns the provider name, which is used to describe the provider within the GUI. ...
QList< const QgsProcessingAlgorithm *> algorithms() const
Returns a list of algorithms supplied by this provider.
This class is a composition of two QSettings instances:
Definition: qgssettings.h:58
QVariant value(const QString &key, const QVariant &defaultValue=QVariant(), Section section=NoSection) const
Returns the value for setting key.
virtual QString name() const =0
Returns the algorithm name, used for identifying the algorithm.
virtual QString helpId() const
Returns the provider help id string, used for creating QgsHelp urls for algorithms belong to this pro...
static QString iconPath(const QString &iconFile)
Returns path to the desired icon file.
virtual QStringList supportedOutputRasterLayerExtensions() const
Returns a list of the raster format file extensions supported by this provider.
static QIcon getThemeIcon(const QString &name)
Helper to get a theme icon.
virtual bool supportsNonFileBasedOutput() const
Returns true if the provider supports non-file based outputs (such as memory layers or direct databas...
virtual QString svgIconPath() const
Returns a path to an SVG version of the provider&#39;s icon.
Abstract base class for processing algorithms.
virtual void initAlgorithm(const QVariantMap &configuration=QVariantMap())=0
Initializes the algorithm using the specified configuration.
QgsProcessingProvider(QObject *parent=nullptr)
Constructor for QgsProcessingProvider.
static QStringList supportedFormatExtensions(RasterFormatOptions options=SortRecommended)
Returns a list of file extensions for supported formats.
virtual bool isActive() const
Returns true if the provider is active and able to run algorithms.
virtual QString id() const =0
Returns the unique provider id, used for identifying the provider.
virtual QString defaultRasterFileExtension() const
Returns the default file extension to use for raster outputs created by the provider.
virtual void loadAlgorithms()=0
Loads all algorithms belonging to this provider.
static void logMessage(const QString &message, const QString &tag=QString(), Qgis::MessageLevel level=Qgis::Warning, bool notifyUser=true)
Adds a message to the log instance (and creates it if necessary).
static QStringList supportedFormatExtensions(VectorFormatOptions options=SortRecommended)
Returns a list of file extensions for supported formats, e.g "shp", "gpkg".
void refreshAlgorithms()
Refreshes the algorithms available from the provider, causing it to re-populate with all associated a...
virtual QString defaultVectorFileExtension(bool hasGeometry=true) const
Returns the default file extension to use for vector outputs created by the provider.
const QgsProcessingAlgorithm * algorithm(const QString &name) const
Returns the matching algorithm by name, or a nullptr if no matching algorithm is contained by this pr...
bool addAlgorithm(QgsProcessingAlgorithm *algorithm)
Adds an algorithm to the provider.
virtual QIcon icon() const
Returns an icon for the provider.
virtual QString longName() const
Returns the a longer version of the provider name, which can include extra details such as version nu...
virtual QStringList supportedOutputVectorLayerExtensions() const
Returns a list of the vector format file extensions supported by this provider.
void algorithmsLoaded()
Emitted when the provider has loaded (or refreshed) its list of available algorithms.