QGIS API Documentation  3.8.0-Zanzibar (11aff65)
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 {
54 }
55 
57 {
58  const auto constMProviders = mProviders;
59  for ( QgsProcessingProvider *p : constMProviders )
60  {
61  removeProvider( p );
62  }
63 
64  const auto parameterTypes = mParameterTypes.values();
65 
67  {
68  removeParameterType( type );
69  }
70 }
71 
73 {
74  if ( !provider )
75  return false;
76 
77  if ( mProviders.contains( provider->id() ) )
78  {
79  QgsLogger::warning( QStringLiteral( "Duplicate provider %1 registered" ).arg( provider->id() ) );
80  delete provider;
81  return false;
82  }
83 
84  if ( !provider->load() )
85  {
86  QgsLogger::warning( QStringLiteral( "Provider %1 cannot load" ).arg( provider->id() ) );
87  delete provider;
88  return false;
89  }
90 
91  provider->setParent( this );
92  mProviders[ provider->id()] = provider;
93  emit providerAdded( provider->id() );
94  return true;
95 }
96 
98 {
99  if ( !provider )
100  return false;
101 
102  QString id = provider->id();
103 
104  if ( !mProviders.contains( id ) )
105  return false;
106 
107  provider->unload();
108 
109  delete mProviders.take( id );
110  emit providerRemoved( id );
111  return true;
112 }
113 
114 bool QgsProcessingRegistry::removeProvider( const QString &providerId )
115 {
116  QgsProcessingProvider *p = providerById( providerId );
117  return removeProvider( p );
118 }
119 
121 {
122  return mProviders.value( id, nullptr );
123 }
124 
125 QList< const QgsProcessingAlgorithm * > QgsProcessingRegistry::algorithms() const
126 {
127  QList< const QgsProcessingAlgorithm * > algs;
128  QMap<QString, QgsProcessingProvider *>::const_iterator it = mProviders.constBegin();
129  for ( ; it != mProviders.constEnd(); ++it )
130  {
131  algs.append( it.value()->algorithms() );
132  }
133  return algs;
134 }
135 
137 {
138  QMap<QString, QgsProcessingProvider *>::const_iterator it = mProviders.constBegin();
139  for ( ; it != mProviders.constEnd(); ++it )
140  {
141  const auto constAlgorithms = it.value()->algorithms();
142  for ( const QgsProcessingAlgorithm *alg : constAlgorithms )
143  if ( alg->id() == id )
144  return alg;
145  }
146 
147  // try mapping 'qgis' algs to 'native' algs - this allows us to freely move algorithms
148  // from the python 'qgis' provider to the c++ 'native' provider without breaking API
149  // or existing models
150  if ( id.startsWith( QLatin1String( "qgis:" ) ) )
151  {
152  QString newId = QStringLiteral( "native:" ) + id.mid( 5 );
153  return algorithmById( newId );
154  }
155  return nullptr;
156 }
157 
158 QgsProcessingAlgorithm *QgsProcessingRegistry::createAlgorithmById( const QString &id, const QVariantMap &configuration ) const
159 {
160  const QgsProcessingAlgorithm *alg = algorithmById( id );
161  if ( !alg )
162  return nullptr;
163 
164  std::unique_ptr< QgsProcessingAlgorithm > creation( alg->create( configuration ) );
165  return creation.release();
166 }
167 
169 {
170  if ( !mParameterTypes.contains( type->id() ) )
171  {
172  mParameterTypes.insert( type->id(), type );
173  emit parameterTypeAdded( type );
174  return true;
175  }
176  else
177  {
178  QgsLogger::warning( QStringLiteral( "Duplicate parameter type %1 (\"%2\") registered" ).arg( type->id(), type->name() ) );
179 
180  if ( mParameterTypes.value( type->id() ) != type )
181  delete type;
182 
183  return false;
184  }
185 }
186 
188 {
189  mParameterTypes.remove( type->id() );
190  emit parameterTypeRemoved( type );
191  delete type;
192 }
193 
195 {
196  return mParameterTypes.value( id );
197 }
198 
199 QList<QgsProcessingParameterType *> QgsProcessingRegistry::parameterTypes() const
200 {
201  return mParameterTypes.values();
202 }
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:46
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:121
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.
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 scale parameter for processing algorithms.
A authentication configuration parameter for processing algorithms.
QgsProcessingRegistry(QObject *parent=nullptr)
Constructor for QgsProcessingRegistry.
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.