QGIS API Documentation 3.41.0-Master (3440c17df1d)
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qgsvectorlayerexporter.cpp
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1/***************************************************************************
2 qgsvectorlayerexporter.cpp
3 -------------------
4 begin : Thu Aug 25 2011
5 copyright : (C) 2011 by Giuseppe Sucameli
6 email : brush.tyler at gmail.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
19#include "qgsfields.h"
20#include "qgsfeature.h"
21#include "qgsfeatureiterator.h"
22#include "qgsgeometry.h"
23#include "qgslogger.h"
24#include "qgsmessagelog.h"
28#include "moc_qgsvectorlayerexporter.cpp"
29#include "qgsproviderregistry.h"
30#include "qgsexception.h"
32#include "qgsvectorlayer.h"
33#include "qgsabstractgeometry.h"
35
36#include <QProgressDialog>
37
39 const QString &uri,
40 const QgsFields &fields,
41 Qgis::WkbType geometryType,
42 const QgsCoordinateReferenceSystem &destCRS,
43 bool overwrite,
44 QMap<int, int> *oldToNewAttrIdx,
45 QString *errorMessage,
46 const QMap<QString, QVariant> *options
47);
48
49
51 const QString &providerKey,
52 const QgsFields &fields,
53 Qgis::WkbType geometryType,
55 bool overwrite,
56 const QMap<QString, QVariant> &options,
58 : mErrorCount( 0 )
59 , mAttributeCount( -1 )
60
61{
62 mProvider = nullptr;
63
64 QMap<QString, QVariant> modifiedOptions( options );
65
66 if ( providerKey == QLatin1String( "ogr" ) &&
67 options.contains( QStringLiteral( "driverName" ) ) &&
68 ( options[ QStringLiteral( "driverName" ) ].toString().compare( QLatin1String( "GPKG" ), Qt::CaseInsensitive ) == 0 ||
69 options[ QStringLiteral( "driverName" ) ].toString().compare( QLatin1String( "SQLite" ), Qt::CaseInsensitive ) == 0 ) )
70 {
71 if ( geometryType != Qgis::WkbType::NoGeometry )
72 {
73 // For GPKG/Spatialite, we explicitly ask not to create a spatial index at
74 // layer creation since this would slow down inserts. Defer its creation
75 // to end of exportLayer() or destruction of this object.
76 QStringList modifiedLayerOptions;
77 if ( options.contains( QStringLiteral( "layerOptions" ) ) )
78 {
79 const QStringList layerOptions = options.value( QStringLiteral( "layerOptions" ) ).toStringList();
80 for ( const QString &layerOption : layerOptions )
81 {
82 if ( layerOption.compare( QLatin1String( "SPATIAL_INDEX=YES" ), Qt::CaseInsensitive ) == 0 ||
83 layerOption.compare( QLatin1String( "SPATIAL_INDEX=ON" ), Qt::CaseInsensitive ) == 0 ||
84 layerOption.compare( QLatin1String( "SPATIAL_INDEX=TRUE" ), Qt::CaseInsensitive ) == 0 ||
85 layerOption.compare( QLatin1String( "SPATIAL_INDEX=1" ), Qt::CaseInsensitive ) == 0 )
86 {
87 // do nothing
88 }
89 else if ( layerOption.compare( QLatin1String( "SPATIAL_INDEX=NO" ), Qt::CaseInsensitive ) == 0 ||
90 layerOption.compare( QLatin1String( "SPATIAL_INDEX=OFF" ), Qt::CaseInsensitive ) == 0 ||
91 layerOption.compare( QLatin1String( "SPATIAL_INDEX=FALSE" ), Qt::CaseInsensitive ) == 0 ||
92 layerOption.compare( QLatin1String( "SPATIAL_INDEX=0" ), Qt::CaseInsensitive ) == 0 )
93 {
94 mCreateSpatialIndex = false;
95 }
96 else
97 {
98 modifiedLayerOptions << layerOption;
99 }
100 }
101 }
102 modifiedLayerOptions << QStringLiteral( "SPATIAL_INDEX=FALSE" );
103 modifiedOptions[ QStringLiteral( "layerOptions" ) ] = modifiedLayerOptions;
104 }
105 }
106
107 // create an empty layer
108 QString errMsg;
110 mError = pReg->createEmptyLayer( providerKey, uri, fields, geometryType, crs, overwrite, mOldToNewAttrIdx,
111 errMsg, !modifiedOptions.isEmpty() ? &modifiedOptions : nullptr );
112
114 {
115 mErrorMessage = errMsg;
116 return;
117 }
118
119 const auto constMOldToNewAttrIdx = mOldToNewAttrIdx;
120 for ( const int idx : constMOldToNewAttrIdx )
121 {
122 if ( idx > mAttributeCount )
123 mAttributeCount = idx;
124 }
125
126 mAttributeCount++;
127
128 QgsDebugMsgLevel( QStringLiteral( "Created empty layer" ), 2 );
129
130 QString uriUpdated( uri );
131 // HACK sorry...
132 if ( providerKey == QLatin1String( "ogr" ) )
133 {
134 QString layerName;
135 if ( options.contains( QStringLiteral( "layerName" ) ) )
136 layerName = options.value( QStringLiteral( "layerName" ) ).toString();
137 if ( !layerName.isEmpty() )
138 {
139 uriUpdated += QLatin1String( "|layername=" );
140 uriUpdated += layerName;
141 }
142 }
143
144 // Oracle specific HACK: we cannot guess the geometry type when there is no rows, so we need
145 // to force it in the uri
146 if ( providerKey == QLatin1String( "oracle" ) )
147 {
148 uriUpdated += QStringLiteral( " type=%1" ).arg( QgsWkbTypes::displayString( geometryType ) );
149 }
150
151 const QgsDataProvider::ProviderOptions providerOptions;
152 QgsVectorDataProvider *vectorProvider = qobject_cast< QgsVectorDataProvider * >( pReg->createProvider( providerKey, uriUpdated, providerOptions ) );
153 if ( !vectorProvider || !vectorProvider->isValid() || ( vectorProvider->capabilities() & Qgis::VectorProviderCapability::AddFeatures ) == 0 )
154 {
156 mErrorMessage = QObject::tr( "Loading of layer failed" );
157
158 delete vectorProvider;
159 return;
160 }
161
162 // If the result is a geopackage layer and there is already a field name FID requested which
163 // might contain duplicates, make sure to generate a new field with a unique name instead
164 // that will be filled by ogr with unique values.
165
166 // HACK sorry
167 const QString path = QgsProviderRegistry::instance()->decodeUri( QStringLiteral( "ogr" ), uri ).value( QStringLiteral( "path" ) ).toString();
168 if ( sinkFlags.testFlag( QgsFeatureSink::SinkFlag::RegeneratePrimaryKey ) && path.endsWith( QLatin1String( ".gpkg" ), Qt::CaseInsensitive ) )
169 {
170 const QString fidName = options.value( QStringLiteral( "FID" ), QStringLiteral( "FID" ) ).toString();
171 const int fidIdx = fields.lookupField( fidName );
172 if ( fidIdx != -1 )
173 {
174 mOldToNewAttrIdx.remove( fidIdx );
175 }
176 }
177
178 mProvider = vectorProvider;
180}
181
183{
184 flushBuffer();
185
186 if ( mCreateSpatialIndex )
187 {
188 createSpatialIndex();
189 }
190
191 delete mProvider;
192}
193
198
200{
201 return mErrorMessage;
202}
203
208
210{
211 QgsFeatureList::iterator fIt = features.begin();
212 bool result = true;
213 for ( ; fIt != features.end(); ++fIt )
214 {
215 result = result && addFeature( *fIt, flags );
216 }
217 return result;
218}
219
221{
222 const QgsAttributes attrs = feat.attributes();
223
224 QgsFeature newFeat;
225 if ( feat.hasGeometry() )
226 newFeat.setGeometry( feat.geometry() );
227
228 newFeat.initAttributes( mAttributeCount );
229
230 for ( int i = 0; i < attrs.count(); ++i )
231 {
232 // add only mapped attributes (un-mapped ones will not be present in the
233 // destination layer)
234 const int dstIdx = mOldToNewAttrIdx.value( i, -1 );
235 if ( dstIdx < 0 )
236 continue;
237
238 QgsDebugMsgLevel( QStringLiteral( "moving field from pos %1 to %2" ).arg( i ).arg( dstIdx ), 3 );
239 newFeat.setAttribute( dstIdx, attrs.at( i ) );
240 }
241
242 mFeatureBuffer.append( newFeat );
243 mFeatureBufferMemoryUsage += newFeat.approximateMemoryUsage();
244
245 if ( mFeatureBufferMemoryUsage >= 100 * 1000 * 1000 )
246 {
247 return flushBuffer();
248 }
249
250 return true;
251}
252
254{
255 return mErrorMessage;
256}
257
259{
260 mFeatureBufferMemoryUsage = 0;
261 if ( mFeatureBuffer.count() <= 0 )
262 return true;
263
264 if ( !mProvider->addFeatures( mFeatureBuffer, QgsFeatureSink::FastInsert ) )
265 {
266 const QStringList errors = mProvider->errors();
267 mProvider->clearErrors();
268
269 mErrorMessage = QObject::tr( "Creation error for features from #%1 to #%2. Provider errors were: \n%3" )
270 .arg( mFeatureBuffer.first().id() )
271 .arg( mFeatureBuffer.last().id() )
272 .arg( errors.join( QLatin1Char( '\n' ) ) );
273
275 mErrorCount += mFeatureBuffer.count();
276
277 mFeatureBuffer.clear();
278 QgsDebugError( mErrorMessage );
279 return false;
280 }
281
282 mFeatureBuffer.clear();
283 return true;
284}
285
286bool QgsVectorLayerExporter::createSpatialIndex()
287{
288 mCreateSpatialIndex = false;
289 if ( mProvider && ( mProvider->capabilities() & Qgis::VectorProviderCapability::CreateSpatialIndex ) != 0 )
290 {
291 return mProvider->createSpatialIndex();
292 }
293 else
294 {
295 return true;
296 }
297}
298
300 const QString &uri,
301 const QString &providerKey,
302 const QgsCoordinateReferenceSystem &destCRS,
303 bool onlySelected,
304 QString *errorMessage,
305 const QMap<QString, QVariant> &options,
306 QgsFeedback *feedback )
307{
310 bool shallTransform = false;
311
312 if ( !layer )
314
315 if ( destCRS.isValid() )
316 {
317 // This means we should transform
318 outputCRS = destCRS;
319 shallTransform = true;
320 }
321 else
322 {
323 // This means we shouldn't transform, use source CRS as output (if defined)
324 outputCRS = layer->crs();
325 }
326
327
328 bool overwrite = false;
329 bool forceSinglePartGeom = false;
330 QMap<QString, QVariant> providerOptions = options;
331 if ( !options.isEmpty() )
332 {
333 overwrite = providerOptions.take( QStringLiteral( "overwrite" ) ).toBool();
334 forceSinglePartGeom = providerOptions.take( QStringLiteral( "forceSinglePartGeometryType" ) ).toBool();
335 }
336
337 QgsFields fields = layer->fields();
338
339 Qgis::WkbType wkbType = layer->wkbType();
340
341 bool convertGeometryToSinglePart = false;
342 if ( forceSinglePartGeom && QgsWkbTypes::isMultiType( wkbType ) )
343 {
344 wkbType = QgsWkbTypes::singleType( wkbType );
345 convertGeometryToSinglePart = true;
346 }
347
348 QgsVectorLayerExporter *writer =
349 new QgsVectorLayerExporter( uri, providerKey, fields, wkbType, outputCRS, overwrite, providerOptions );
350
351 // check whether file creation was successful
352 const Qgis::VectorExportResult err = writer->errorCode();
354 {
355 if ( errorMessage )
356 *errorMessage = writer->errorMessage();
357 delete writer;
358 return err;
359 }
360
361 if ( errorMessage )
362 {
363 errorMessage->clear();
364 }
365
366 QgsFeature fet;
367
369 if ( wkbType == Qgis::WkbType::NoGeometry )
371 if ( onlySelected )
372 req.setFilterFids( layer->selectedFeatureIds() );
373
374 QgsFeatureIterator fit = layer->getFeatures( req );
375
376 // Create our transform
377 if ( destCRS.isValid() )
378 {
379 ct = QgsCoordinateTransform( layer->crs(), destCRS, layer->transformContext() );
380 }
381
382 // Check for failure
383 if ( !ct.isValid() )
384 shallTransform = false;
385
386 long long n = 0;
387 const long long approxTotal = onlySelected ? layer->selectedFeatureCount() : layer->featureCount();
388
389 if ( errorMessage )
390 {
391 *errorMessage = QObject::tr( "Feature write errors:" );
392 }
393
394 bool canceled = false;
395
396 // write all features
397 while ( fit.nextFeature( fet ) )
398 {
399 if ( feedback && feedback->isCanceled() )
400 {
401 canceled = true;
402 if ( errorMessage )
403 {
404 *errorMessage += '\n' + QObject::tr( "Import was canceled at %1 of %2" ).arg( n ).arg( approxTotal );
405 }
406 break;
407 }
408
409 if ( writer->errorCount() > 1000 )
410 {
411 if ( errorMessage )
412 {
413 *errorMessage += '\n' + QObject::tr( "Stopping after %n error(s)", nullptr, writer->errorCount() );
414 }
415 break;
416 }
417
418 if ( shallTransform )
419 {
420 try
421 {
422 if ( fet.hasGeometry() )
423 {
424 QgsGeometry g = fet.geometry();
425 g.transform( ct );
426 fet.setGeometry( g );
427 }
428 }
429 catch ( QgsCsException &e )
430 {
431 delete writer;
432
433 const QString msg = QObject::tr( "Failed to transform feature with ID '%1'. Writing stopped. (Exception: %2)" )
434 .arg( fet.id() ).arg( e.what() );
435 QgsMessageLog::logMessage( msg, QObject::tr( "Vector import" ) );
436 if ( errorMessage )
437 *errorMessage += '\n' + msg;
438
440 }
441 }
442
443 // Handles conversion to single-part
444 if ( convertGeometryToSinglePart && fet.geometry().isMultipart() )
445 {
446 QgsGeometry singlePartGeometry { fet.geometry() };
447 // We want a failure if the geometry cannot be converted to single-part without data loss!
448 // check if there are more than one part
449 const QgsGeometryCollection *c = qgsgeometry_cast<const QgsGeometryCollection *>( singlePartGeometry.constGet() );
450 if ( ( c && c->partCount() > 1 ) || ! singlePartGeometry.convertToSingleType() )
451 {
452 delete writer;
453 const QString msg = QObject::tr( "Failed to transform a feature with ID '%1' to single part. Writing stopped." )
454 .arg( fet.id() );
455 QgsMessageLog::logMessage( msg, QObject::tr( "Vector import" ) );
456 if ( errorMessage )
457 *errorMessage += '\n' + msg;
459 }
460 fet.setGeometry( singlePartGeometry );
461 }
462
463 if ( !writer->addFeature( fet ) )
464 {
466 {
467 *errorMessage += '\n' + writer->errorMessage();
468 }
469 }
470 n++;
471
472 if ( feedback )
473 {
474 feedback->setProgress( 100.0 * static_cast< double >( n ) / approxTotal );
475 }
476
477 }
478
479 // flush the buffer to be sure that all features are written
480 if ( !writer->flushBuffer() )
481 {
483 {
484 *errorMessage += '\n' + writer->errorMessage();
485 }
486 }
487 const int errors = writer->errorCount();
488
489 if ( writer->mCreateSpatialIndex && !writer->createSpatialIndex() )
490 {
492 {
493 *errorMessage += '\n' + writer->errorMessage();
494 }
495 }
496
497 delete writer;
498
499 if ( errorMessage )
500 {
501 if ( errors > 0 )
502 {
503 *errorMessage += '\n' + QObject::tr( "Only %1 of %2 features written." ).arg( n - errors ).arg( n );
504 }
505 else
506 {
507 errorMessage->clear();
508 }
509 }
510
511 if ( canceled )
513 else if ( errors > 0 )
515
517}
518
519
520//
521// QgsVectorLayerExporterTask
522//
523
524QgsVectorLayerExporterTask::QgsVectorLayerExporterTask( QgsVectorLayer *layer, const QString &uri, const QString &providerKey, const QgsCoordinateReferenceSystem &destinationCrs, const QMap<QString, QVariant> &options, bool ownsLayer )
525 : QgsTask( tr( "Exporting %1" ).arg( layer->name() ), QgsTask::CanCancel )
526 , mLayer( layer )
527 , mOwnsLayer( ownsLayer )
528 , mDestUri( uri )
529 , mDestProviderKey( providerKey )
530 , mDestCrs( destinationCrs )
531 , mOptions( options )
532 , mOwnedFeedback( new QgsFeedback() )
533{
534 if ( mLayer )
535 setDependentLayers( QList< QgsMapLayer * >() << mLayer );
536}
537
538QgsVectorLayerExporterTask *QgsVectorLayerExporterTask::withLayerOwnership( QgsVectorLayer *layer, const QString &uri, const QString &providerKey, const QgsCoordinateReferenceSystem &destinationCrs, const QMap<QString, QVariant> &options )
539{
540 std::unique_ptr< QgsVectorLayerExporterTask > newTask( new QgsVectorLayerExporterTask( layer, uri, providerKey, destinationCrs, options ) );
541 newTask->mOwnsLayer = true;
542 return newTask.release();
543}
544
546{
547 mOwnedFeedback->cancel();
549}
550
552{
553 if ( !mLayer )
554 return false;
555
556 connect( mOwnedFeedback.get(), &QgsFeedback::progressChanged, this, &QgsVectorLayerExporterTask::setProgress );
557
558
560 mLayer.data(), mDestUri, mDestProviderKey, mDestCrs, false, &mErrorMessage,
561 mOptions, mOwnedFeedback.get() );
562
563 return mError == Qgis::VectorExportResult::Success;
564}
565
567{
568 // QgsMapLayer has QTimer member, which must not be destroyed from another thread
569 if ( mOwnsLayer )
570 delete mLayer;
571
572 if ( result )
573 emit exportComplete();
574 else
575 emit errorOccurred( mError, mErrorMessage );
576}
@ AddFeatures
Allows adding features.
@ CreateSpatialIndex
Allows creation of spatial index.
VectorExportResult
Vector layer export result codes.
Definition qgis.h:983
@ Success
No errors were encountered.
@ ErrorInvalidLayer
Could not access newly created destination layer.
@ ErrorFeatureWriteFailed
An error occurred while writing a feature to the destination.
@ UserCanceled
User canceled the export.
@ ErrorProjectingFeatures
An error occurred while reprojecting features to destination CRS.
@ NoGeometry
Geometry is not required. It may still be returned if e.g. required for a filter condition.
QFlags< VectorDataProviderAttributeEditCapability > VectorDataProviderAttributeEditCapabilities
Attribute editing capabilities which may be supported by vector data providers.
Definition qgis.h:566
WkbType
The WKB type describes the number of dimensions a geometry has.
Definition qgis.h:256
@ NoGeometry
No geometry.
A vector of attributes.
This class represents a coordinate reference system (CRS).
bool isValid() const
Returns whether this CRS is correctly initialized and usable.
Class for doing transforms between two map coordinate systems.
bool isValid() const
Returns true if the coordinate transform is valid, ie both the source and destination CRS have been s...
Custom exception class for Coordinate Reference System related exceptions.
virtual bool isValid() const =0
Returns true if this is a valid layer.
QString what() const
Wrapper for iterator of features from vector data provider or vector layer.
bool nextFeature(QgsFeature &f)
Fetch next feature and stores in f, returns true on success.
This class wraps a request for features to a vector layer (or directly its vector data provider).
QgsFeatureRequest & setFlags(Qgis::FeatureRequestFlags flags)
Sets flags that affect how features will be fetched.
QgsFeatureRequest & setFilterFids(const QgsFeatureIds &fids)
Sets the feature IDs that should be fetched.
QFlags< SinkFlag > SinkFlags
@ FastInsert
Use faster inserts, at the cost of updating the passed features to reflect changes made at the provid...
@ RegeneratePrimaryKey
This flag indicates, that a primary key field cannot be guaranteed to be unique and the sink should i...
QFlags< Flag > Flags
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition qgsfeature.h:58
Q_INVOKABLE bool setAttribute(int field, const QVariant &attr)
Sets an attribute's value by field index.
QgsAttributes attributes
Definition qgsfeature.h:67
void initAttributes(int fieldCount)
Initialize this feature with the given number of fields.
QgsFeatureId id
Definition qgsfeature.h:66
int approximateMemoryUsage() const
Returns the approximate RAM usage of the feature, in bytes.
QgsGeometry geometry
Definition qgsfeature.h:69
bool hasGeometry() const
Returns true if the feature has an associated geometry.
void setGeometry(const QgsGeometry &geometry)
Set the feature's geometry.
Base class for feedback objects to be used for cancellation of something running in a worker thread.
Definition qgsfeedback.h:44
bool isCanceled() const
Tells whether the operation has been canceled already.
Definition qgsfeedback.h:53
void progressChanged(double progress)
Emitted when the feedback object reports a progress change.
void setProgress(double progress)
Sets the current progress for the feedback object.
Definition qgsfeedback.h:61
Container of fields for a vector layer.
Definition qgsfields.h:46
Q_INVOKABLE int lookupField(const QString &fieldName) const
Looks up field's index from the field name.
A geometry is the spatial representation of a feature.
Qgis::GeometryOperationResult transform(const QgsCoordinateTransform &ct, Qgis::TransformDirection direction=Qgis::TransformDirection::Forward, bool transformZ=false)
Transforms this geometry as described by the coordinate transform ct.
bool isMultipart() const
Returns true if WKB of the geometry is of WKBMulti* type.
QgsCoordinateReferenceSystem crs
Definition qgsmaplayer.h:83
QgsCoordinateTransformContext transformContext() const
Returns the layer data provider coordinate transform context or a default transform context if the la...
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).
A registry / canonical manager of data providers.
QVariantMap decodeUri(const QString &providerKey, const QString &uri)
Breaks a provider data source URI into its component paths (e.g.
static QgsProviderRegistry * instance(const QString &pluginPath=QString())
Means of accessing canonical single instance.
Qgis::VectorExportResult createEmptyLayer(const QString &providerKey, const QString &uri, const QgsFields &fields, Qgis::WkbType wkbType, const QgsCoordinateReferenceSystem &srs, bool overwrite, QMap< int, int > &oldToNewAttrIdxMap, QString &errorMessage, const QMap< QString, QVariant > *options)
Creates new empty vector layer.
QgsDataProvider * createProvider(const QString &providerKey, const QString &dataSource, const QgsDataProvider::ProviderOptions &options=QgsDataProvider::ProviderOptions(), Qgis::DataProviderReadFlags flags=Qgis::DataProviderReadFlags())
Creates a new instance of a provider.
Abstract base class for long running background tasks.
virtual void cancel()
Notifies the task that it should terminate.
void setDependentLayers(const QList< QgsMapLayer * > &dependentLayers)
Sets a list of layers on which the task depends.
void setProgress(double progress)
Sets the task's current progress.
This is the base class for vector data providers.
virtual bool createSpatialIndex()
Creates a spatial index on the datasource (if supported by the provider type).
void clearErrors()
Clear recorded errors.
QStringList errors() const
Gets recorded errors.
virtual Q_INVOKABLE Qgis::VectorProviderCapabilities capabilities() const
Returns flags containing the supported capabilities.
bool addFeatures(QgsFeatureList &flist, QgsFeatureSink::Flags flags=QgsFeatureSink::Flags()) override
Adds a list of features to the sink.
virtual Qgis::VectorDataProviderAttributeEditCapabilities attributeEditCapabilities() const
Returns the provider's supported attribute editing capabilities.
QgsTask task which performs a QgsVectorLayerExporter layer export operation as a background task.
void finished(bool result) override
If the task is managed by a QgsTaskManager, this will be called after the task has finished (whether ...
QgsVectorLayerExporterTask(QgsVectorLayer *layer, const QString &uri, const QString &providerKey, const QgsCoordinateReferenceSystem &destinationCrs, const QMap< QString, QVariant > &options=QMap< QString, QVariant >(), bool ownsLayer=false)
Constructor for QgsVectorLayerExporterTask.
void exportComplete()
Emitted when exporting the layer is successfully completed.
void errorOccurred(Qgis::VectorExportResult error, const QString &errorMessage)
Emitted when an error occurs which prevented the layer being exported (or if the task is canceled).
void cancel() override
Notifies the task that it should terminate.
static QgsVectorLayerExporterTask * withLayerOwnership(QgsVectorLayer *layer, const QString &uri, const QString &providerKey, const QgsCoordinateReferenceSystem &destinationCrs, const QMap< QString, QVariant > &options=QMap< QString, QVariant >())
Creates a new QgsVectorLayerExporterTask which has ownership over a source layer.
bool run() override
Performs the task's operation.
A convenience class for exporting vector layers to a destination data provider.
bool addFeatures(QgsFeatureList &features, QgsFeatureSink::Flags flags=QgsFeatureSink::Flags()) override
Adds a list of features to the sink.
static Qgis::VectorExportResult exportLayer(QgsVectorLayer *layer, const QString &uri, const QString &providerKey, const QgsCoordinateReferenceSystem &destCRS, bool onlySelected=false, QString *errorMessage=nullptr, const QMap< QString, QVariant > &options=QMap< QString, QVariant >(), QgsFeedback *feedback=nullptr)
Writes the contents of vector layer to a different datasource.
int errorCount() const
Returns the number of error messages encountered during the export.
QString errorMessage() const
Returns any error message encountered during the export.
Qgis::VectorDataProviderAttributeEditCapabilities attributeEditCapabilities() const
Returns the attribute capabilities of the exporter.
~QgsVectorLayerExporter() override
Finalizes the export and closes the new created layer.
QString lastError() const override
Returns the most recent error encountered by the sink, e.g.
bool flushBuffer() override
Flushes any internal buffer which may exist in the sink, causing any buffered features to be added to...
Qgis::VectorExportResult errorCode() const
Returns any encountered error code, or false if no error was encountered.
QgsVectorLayerExporter(const QString &uri, const QString &provider, const QgsFields &fields, Qgis::WkbType geometryType, const QgsCoordinateReferenceSystem &crs, bool overwrite=false, const QMap< QString, QVariant > &options=QMap< QString, QVariant >(), QgsFeatureSink::SinkFlags sinkFlags=QgsFeatureSink::SinkFlags())
Constructor for QgsVectorLayerExporter.
bool addFeature(QgsFeature &feature, QgsFeatureSink::Flags flags=QgsFeatureSink::Flags()) override
Adds a single feature to the sink.
Represents a vector layer which manages a vector based data sets.
long long featureCount(const QString &legendKey) const
Number of features rendered with specified legend key.
QgsFeatureIterator getFeatures(const QgsFeatureRequest &request=QgsFeatureRequest()) const FINAL
Queries the layer for features specified in request.
int selectedFeatureCount() const
Returns the number of features that are selected in this layer.
Q_INVOKABLE const QgsFeatureIds & selectedFeatureIds() const
Returns a list of the selected features IDs in this layer.
Q_INVOKABLE Qgis::WkbType wkbType() const FINAL
Returns the WKBType or WKBUnknown in case of error.
static bool isMultiType(Qgis::WkbType type)
Returns true if the WKB type is a multi type.
static QString displayString(Qgis::WkbType type)
Returns a non-translated display string type for a WKB type, e.g., the geometry name used in WKT geom...
static Qgis::WkbType singleType(Qgis::WkbType type)
Returns the single type for a WKB type.
Definition qgswkbtypes.h:53
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 c
QList< QgsFeature > QgsFeatureList
#define QgsDebugMsgLevel(str, level)
Definition qgslogger.h:39
#define QgsDebugError(str)
Definition qgslogger.h:38
Qgis::VectorExportResult createEmptyLayer_t(const QString &uri, const QgsFields &fields, Qgis::WkbType geometryType, const QgsCoordinateReferenceSystem &destCRS, bool overwrite, QMap< int, int > *oldToNewAttrIdx, QString *errorMessage, const QMap< QString, QVariant > *options)
const QgsCoordinateReferenceSystem & crs
Setting options for creating vector data providers.