QGIS API Documentation  3.12.1-BucureČ™ti (121cc00ff0)
qgsprocessingregistry.cpp
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1 /***************************************************************************
2  qgsprocessingregistry.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 "qgsprocessingregistry.h"
19 #include "qgsvectorfilewriter.h"
21 
23  : QObject( parent )
24 {
55 #if PROJ_VERSION_MAJOR>=6
57 #endif
59 }
60 
62 {
63  const auto constMProviders = mProviders;
64  for ( QgsProcessingProvider *p : constMProviders )
65  {
66  removeProvider( p );
67  }
68 
69  const auto parameterTypes = mParameterTypes.values();
70 
72  {
73  removeParameterType( type );
74  }
75 }
76 
78 {
79  if ( !provider )
80  return false;
81 
82  if ( mProviders.contains( provider->id() ) )
83  {
84  QgsLogger::warning( QStringLiteral( "Duplicate provider %1 registered" ).arg( provider->id() ) );
85  delete provider;
86  return false;
87  }
88 
89  if ( !provider->load() )
90  {
91  QgsLogger::warning( QStringLiteral( "Provider %1 cannot load" ).arg( provider->id() ) );
92  delete provider;
93  return false;
94  }
95 
96  provider->setParent( this );
97  mProviders[ provider->id()] = provider;
98  emit providerAdded( provider->id() );
99  return true;
100 }
101 
103 {
104  if ( !provider )
105  return false;
106 
107  QString id = provider->id();
108 
109  if ( !mProviders.contains( id ) )
110  return false;
111 
112  provider->unload();
113 
114  delete mProviders.take( id );
115  emit providerRemoved( id );
116  return true;
117 }
118 
119 bool QgsProcessingRegistry::removeProvider( const QString &providerId )
120 {
121  QgsProcessingProvider *p = providerById( providerId );
122  return removeProvider( p );
123 }
124 
126 {
127  return mProviders.value( id, nullptr );
128 }
129 
130 QList< const QgsProcessingAlgorithm * > QgsProcessingRegistry::algorithms() const
131 {
132  QList< const QgsProcessingAlgorithm * > algs;
133  QMap<QString, QgsProcessingProvider *>::const_iterator it = mProviders.constBegin();
134  for ( ; it != mProviders.constEnd(); ++it )
135  {
136  algs.append( it.value()->algorithms() );
137  }
138  return algs;
139 }
140 
141 const QgsProcessingAlgorithm *QgsProcessingRegistry::algorithmById( const QString &constId ) const
142 {
143  // allow mapping of algorithm via registered algorithm aliases
144  QString id = mAlgorithmAliases.value( constId, constId );
145 
146  QMap<QString, QgsProcessingProvider *>::const_iterator it = mProviders.constBegin();
147  for ( ; it != mProviders.constEnd(); ++it )
148  {
149  const auto constAlgorithms = it.value()->algorithms();
150  for ( const QgsProcessingAlgorithm *alg : constAlgorithms )
151  if ( alg->id() == id )
152  return alg;
153  }
154 
155  // try mapping 'qgis' algs to 'native' algs - this allows us to freely move algorithms
156  // from the python 'qgis' provider to the c++ 'native' provider without breaking API
157  // or existing models
158  if ( id.startsWith( QLatin1String( "qgis:" ) ) )
159  {
160  QString newId = QStringLiteral( "native:" ) + id.mid( 5 );
161  return algorithmById( newId );
162  }
163  return nullptr;
164 }
165 
166 QgsProcessingAlgorithm *QgsProcessingRegistry::createAlgorithmById( const QString &id, const QVariantMap &configuration ) const
167 {
168  const QgsProcessingAlgorithm *alg = algorithmById( id );
169  if ( !alg )
170  return nullptr;
171 
172  std::unique_ptr< QgsProcessingAlgorithm > creation( alg->create( configuration ) );
173  return creation.release();
174 }
175 
176 void QgsProcessingRegistry::addAlgorithmAlias( const QString &aliasId, const QString &actualId )
177 {
178  mAlgorithmAliases.insert( aliasId, actualId );
179 }
180 
182 {
183  if ( !mParameterTypes.contains( type->id() ) )
184  {
185  mParameterTypes.insert( type->id(), type );
186  emit parameterTypeAdded( type );
187  return true;
188  }
189  else
190  {
191  QgsLogger::warning( QStringLiteral( "Duplicate parameter type %1 (\"%2\") registered" ).arg( type->id(), type->name() ) );
192 
193  if ( mParameterTypes.value( type->id() ) != type )
194  delete type;
195 
196  return false;
197  }
198 }
199 
201 {
202  mParameterTypes.remove( type->id() );
203  emit parameterTypeRemoved( type );
204  delete type;
205 }
206 
208 {
209  return mParameterTypes.value( id );
210 }
211 
212 QList<QgsProcessingParameterType *> QgsProcessingRegistry::parameterTypes() const
213 {
214  return mParameterTypes.values();
215 }
A feature sink parameter for Processing algorithms.
A vector layer destination parameter, for specifying the destination path for a vector layer created ...
bool removeProvider(QgsProcessingProvider *provider)
Removes a provider implementation from the registry (the provider object is deleted).
void providerAdded(const QString &id)
Emitted when a provider has been added to the registry.
#define SIP_TRANSFERTHIS
Definition: qgis_sip.h:53
A coordinate operation parameter for Processing algorithms.
A generic file based destination parameter, for specifying the destination path for a file (non-map l...
A mesh layer parameter for processing algorithms.
static void warning(const QString &msg)
Goes to qWarning.
Definition: qgslogger.cpp:122
virtual QString id() const =0
A static id for this type which will be used for storing this parameter type.
A folder destination parameter, for specifying the destination path for a folder created by the algor...
void removeParameterType(QgsProcessingParameterType *type)
Unregister a custom parameter type from processing.
A numeric range parameter for processing algorithms.
An expression parameter for processing algorithms.
Abstract base class for processing providers.
const QgsProcessingAlgorithm * algorithmById(const QString &id) const
Finds an algorithm by its ID.
A vector layer or feature source field parameter for processing algorithms.
QgsProcessingParameterType * parameterType(const QString &id) const
Returns the parameter type registered for id.
void parameterTypeAdded(QgsProcessingParameterType *type)
Emitted when a new parameter type has been added to the registry.
A numeric parameter for processing algorithms.
A distance parameter for processing algorithms.
Abstract base class for processing algorithms.
A string parameter for processing algorithms.
bool addParameterType(QgsProcessingParameterType *type)
Register a new parameter type for processing.
QgsProcessingProvider * providerById(const QString &id)
Returns a matching provider by provider ID.
void addAlgorithmAlias(const QString &aliasId, const QString &actualId)
Adds a new alias to an existing algorithm.
A vector layer parameter for processing algorithms.
A boolean parameter for processing algorithms.
A generic map layer parameter for processing algorithms.
An input file or folder parameter for processing algorithms.
void providerRemoved(const QString &id)
Emitted when a provider is removed from the registry.
A raster layer parameter for processing algorithms.
QList< const QgsProcessingAlgorithm * > algorithms() const
Returns a list of all available algorithms from registered providers.
A raster layer destination parameter, for specifying the destination path for a raster layer created ...
virtual QString id() const =0
Returns the unique provider id, used for identifying the provider.
virtual QString name() const =0
A human readable and translatable short name for this parameter type.
A color parameter for Processing algorithms.
A scale parameter for processing algorithms.
A authentication configuration parameter for processing algorithms.
QgsProcessingRegistry(QObject *parent=nullptr)
Constructor for QgsProcessingRegistry.
A map theme parameter for Processing algorithms.
virtual bool load()
Loads the provider.
QgsProcessingAlgorithm * createAlgorithmById(const QString &id, const QVariantMap &configuration=QVariantMap()) const
Creates a new instance of an algorithm by its ID.
A point parameter for processing algorithms.
bool addProvider(QgsProcessingProvider *provider)
Add a processing provider to the registry.
A table (matrix) parameter for processing algorithms.
A parameter for processing algorithms which accepts multiple map layers.
A crs parameter for processing algorithms.
Makes metadata of processing parameters available.
void parameterTypeRemoved(QgsProcessingParameterType *type)
Emitted when a parameter type has been removed from the registry and is about to be deleted...
An input feature source (such as vector layers) parameter for processing algorithms.
A rectangular map extent parameter for processing algorithms.
QList< QgsProcessingParameterType * > parameterTypes() const
Returns a list with all known parameter types.
An enum based parameter for processing algorithms, allowing for selection from predefined values...
virtual void unload()
Unloads the provider.
A print layout parameter for Processing algorithms.
A raster band parameter for Processing algorithms.
A print layout item parameter for Processing algorithms.
QgsProcessingAlgorithm * create(const QVariantMap &configuration=QVariantMap()) const SIP_THROW(QgsProcessingException)
Creates a copy of the algorithm, ready for execution.