QGIS API Documentation 3.39.0-Master (67e056379ed)
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qgsalgorithmexporttopostgresql.cpp
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1/***************************************************************************
2 qgsalgorithmexporttopostgresql.cpp
3 ---------------------
4 begin : November 2021
5 copyright : (C) 2021 by Clemens Raffler
6 email : clemens dot raffler 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 "qgsproviderregistry.h"
20#include "qgsprovidermetadata.h"
22#include "qgsvectorfilewriter.h"
23
25
26QString QgsExportToPostgresqlAlgorithm::name() const
27{
28 return QStringLiteral( "importintopostgis" );
29}
30
31QString QgsExportToPostgresqlAlgorithm::displayName() const
32{
33 return QStringLiteral( "Export to PostgreSQL" );
34}
35
36QStringList QgsExportToPostgresqlAlgorithm::tags() const
37{
38 return QObject::tr( "export,import,postgis,table,layer,into,copy" ).split( ',' );
39}
40
41QString QgsExportToPostgresqlAlgorithm::group() const
42{
43 return QStringLiteral( "Database" );
44}
45
46QString QgsExportToPostgresqlAlgorithm::groupId() const
47{
48 return QStringLiteral( "database" );
49}
50
51void QgsExportToPostgresqlAlgorithm::initAlgorithm( const QVariantMap & )
52{
53 addParameter( new QgsProcessingParameterFeatureSource( QStringLiteral( "INPUT" ), QObject::tr( "Layer to export" ), QList<int>() << static_cast< int >( Qgis::ProcessingSourceType::Vector ) ) );
54 addParameter( new QgsProcessingParameterProviderConnection( QStringLiteral( "DATABASE" ), QObject::tr( "Database (connection name)" ), QStringLiteral( "postgres" ) ) );
55 addParameter( new QgsProcessingParameterDatabaseSchema( QStringLiteral( "SCHEMA" ), QObject::tr( "Schema (schema name)" ), QStringLiteral( "DATABASE" ), QStringLiteral( "public" ), true ) );
56 addParameter( new QgsProcessingParameterDatabaseTable( QStringLiteral( "TABLENAME" ), QObject::tr( "Table to export to (leave blank to use layer name)" ), QStringLiteral( "DATABASE" ), QStringLiteral( "SCHEMA" ), QVariant(), true, true ) );
57 addParameter( new QgsProcessingParameterField( QStringLiteral( "PRIMARY_KEY" ), QObject::tr( "Primary key field" ), QVariant(), QStringLiteral( "INPUT" ), Qgis::ProcessingFieldParameterDataType::Any, false, true ) );
58 addParameter( new QgsProcessingParameterString( QStringLiteral( "GEOMETRY_COLUMN" ), QObject::tr( "Geometry column" ), QStringLiteral( "geom" ) ) );
59 addParameter( new QgsProcessingParameterString( QStringLiteral( "ENCODING" ), QObject::tr( "Encoding" ), QStringLiteral( "UTF-8" ), false, true ) );
60 addParameter( new QgsProcessingParameterBoolean( QStringLiteral( "OVERWRITE" ), QObject::tr( "Overwrite" ), true ) );
61 addParameter( new QgsProcessingParameterBoolean( QStringLiteral( "CREATEINDEX" ), QObject::tr( "Create spatial index" ), true ) );
62 addParameter( new QgsProcessingParameterBoolean( QStringLiteral( "LOWERCASE_NAMES" ), QObject::tr( "Convert field names to lowercase" ), true ) );
63 addParameter( new QgsProcessingParameterBoolean( QStringLiteral( "DROP_STRING_LENGTH" ), QObject::tr( "Drop length constraints on character fields" ), false ) );
64 addParameter( new QgsProcessingParameterBoolean( QStringLiteral( "FORCE_SINGLEPART" ), QObject::tr( "Create single-part geometries instead of multipart" ), false ) );
65}
66
67QString QgsExportToPostgresqlAlgorithm::shortHelpString() const
68{
69 return QObject::tr( "This algorithm exports a vector layer to a PostgreSQL "
70 "database, creating a new table.\n\n"
71 "Prior to this a connection between QGIS and the PostgreSQL "
72 "database has to be created (for example through the QGIS Browser panel)."
73 );
74}
75
76QString QgsExportToPostgresqlAlgorithm::shortDescription() const
77{
78 return QObject::tr( "Exports a vector layer to a PostgreSQL database" );
79}
80
81QgsExportToPostgresqlAlgorithm *QgsExportToPostgresqlAlgorithm::createInstance() const
82{
83 return new QgsExportToPostgresqlAlgorithm();
84}
85
86bool QgsExportToPostgresqlAlgorithm::prepareAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback * )
87{
88 mSource.reset( parameterAsSource( parameters, QStringLiteral( "INPUT" ), context ) );
89 if ( !mSource )
90 throw QgsProcessingException( invalidSourceError( parameters, QStringLiteral( "INPUT" ) ) );
91
92 const QString connectionName = parameterAsConnectionName( parameters, QStringLiteral( "DATABASE" ), context );
93
94 try
95 {
96 QgsProviderMetadata *md = QgsProviderRegistry::instance()->providerMetadata( QStringLiteral( "postgres" ) );
97 mConn.reset( static_cast<QgsAbstractDatabaseProviderConnection *>( md->createConnection( connectionName ) ) );
98 }
100 {
101 QgsProcessingException( QObject::tr( "Could not retrieve connection details for %1" ).arg( connectionName ) );
102 }
103
104 mSchema = parameterAsSchema( parameters, QStringLiteral( "SCHEMA" ), context );
105 mPrimaryKeyField = parameterAsString( parameters, QStringLiteral( "PRIMARY_KEY" ), context );
106 mEncoding = parameterAsString( parameters, QStringLiteral( "ENCODING" ), context );
107 mOverwrite = parameterAsBoolean( parameters, QStringLiteral( "OVERWRITE" ), context );
108
109 mTable = parameterAsDatabaseTableName( parameters, QStringLiteral( "TABLENAME" ), context ).trimmed();
110 if ( mTable.isEmpty() )
111 {
112 mTable = mSource->sourceName();
113 mTable = mTable.replace( '.', '_' );
114 }
115 mTable = mTable.replace( ' ', QString() ).right( 63 );
116
117 mGeomColumn = parameterAsString( parameters, QStringLiteral( "GEOMETRY_COLUMN" ), context );
118 if ( mGeomColumn.isEmpty() )
119 mGeomColumn = QStringLiteral( "geom" );
120 if ( mSource->wkbType() == Qgis::WkbType::NoGeometry )
121 mGeomColumn.clear();
122
123 mCreateIndex = parameterAsBoolean( parameters, QStringLiteral( "CREATEINDEX" ), context );
124
125 if ( mOverwrite )
126 mOptions[QStringLiteral( "overwrite" )] = true;
127 if ( parameterAsBoolean( parameters, QStringLiteral( "LOWERCASE_NAMES" ), context ) )
128 {
129 mOptions[QStringLiteral( "lowercaseFieldNames" )] = true;
130 mGeomColumn = mGeomColumn.toLower();
131 }
132 if ( parameterAsBoolean( parameters, QStringLiteral( "DROP_STRING_LENGTH" ), context ) )
133 mOptions[QStringLiteral( "dropStringConstraints" )] = true;
134 if ( parameterAsBoolean( parameters, QStringLiteral( "FORCE_SINGLEPART" ), context ) )
135 mOptions[QStringLiteral( "forceSinglePartGeometryType" )] = true;
136 if ( !mEncoding.isEmpty() )
137 mOptions[QStringLiteral( "fileEncoding" )] = mEncoding;
138
139 return true;
140}
141
142QVariantMap QgsExportToPostgresqlAlgorithm::processAlgorithm( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback )
143{
144 Q_UNUSED( parameters );
145 Q_UNUSED( context );
146
147 QgsDataSourceUri uri = QgsDataSourceUri( mConn->uri() );
148 uri.setSchema( mSchema );
149 uri.setTable( mTable );
150 uri.setKeyColumn( mPrimaryKeyField );
151 uri.setGeometryColumn( mGeomColumn );
152
153 std::unique_ptr< QgsVectorLayerExporter > exporter = std::make_unique< QgsVectorLayerExporter >( uri.uri(), mProviderName, mSource->fields(), mSource->wkbType(), mSource->sourceCrs(), mOverwrite, mOptions );
154
155 if ( exporter->errorCode() != Qgis::VectorExportResult::Success )
156 throw QgsProcessingException( QObject::tr( "Error exporting to PostGIS\n%1" ).arg( exporter->errorMessage() ) );
157
158 QgsFeatureIterator featureIterator = mSource->getFeatures();
159
160 const double progressStep = ( mSource->featureCount() ) ? 100.0 / mSource->featureCount() : 0.0;
161
162 qgssize i = 0;
163 QgsFeature f;
164 while ( featureIterator.nextFeature( f ) )
165 {
166 if ( feedback->isCanceled() )
167 break;
168
169 if ( !exporter->addFeature( f, QgsFeatureSink::FastInsert ) )
170 feedback->reportError( exporter->errorMessage() );
171
172 feedback->setProgress( i * progressStep );
173 i++;
174 }
175 exporter->flushBuffer();
176
177 if ( exporter->errorCode() != Qgis::VectorExportResult::Success )
178 throw QgsProcessingException( QObject::tr( "Error exporting to PostGIS\n%1" ).arg( exporter->errorMessage() ) );
179
180 exporter.reset();
181
182 if ( !mGeomColumn.isEmpty() && mCreateIndex )
183 {
184 try
185 {
187 opt.geometryColumnName = mGeomColumn;
188 mConn->createSpatialIndex( mSchema, mTable, opt );
189 }
191 {
192 throw QgsProcessingException( QObject::tr( "Error creating spatial index:\n%1" ).arg( ex.what() ) );
193 }
194 }
195
196 try
197 {
198 mConn->vacuum( mSchema, mTable );
199 }
201 {
202 feedback->reportError( QObject::tr( "Error vacuuming table:\n{0}" ).arg( ex.what() ) );
203 }
204
205 QVariantMap outputs;
206 return outputs;
207}
@ Vector
Tables (i.e. vector layers with or without geometry). When used for a sink this indicates the sink ha...
@ Success
No errors were encountered.
@ NoGeometry
No geometry.
The QgsAbstractDatabaseProviderConnection class provides common functionality for DB based connection...
Class for storing the component parts of a RDBMS data source URI (e.g.
void setSchema(const QString &schema)
Sets the scheme for the URI.
void setTable(const QString &table)
Sets table to table.
void setGeometryColumn(const QString &geometryColumn)
Sets geometry column name to geometryColumn.
QString uri(bool expandAuthConfig=true) const
Returns the complete URI as a string.
void setKeyColumn(const QString &column)
Sets the name of the (primary) key column.
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.
@ FastInsert
Use faster inserts, at the cost of updating the passed features to reflect changes made at the provid...
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition qgsfeature.h:58
bool isCanceled() const
Tells whether the operation has been canceled already.
Definition qgsfeedback.h:53
void setProgress(double progress)
Sets the current progress for the feedback object.
Definition qgsfeedback.h:61
Contains information about the context in which a processing algorithm is executed.
Custom exception class for processing related exceptions.
Base class for providing feedback from a processing algorithm.
virtual void reportError(const QString &error, bool fatalError=false)
Reports that the algorithm encountered an error while executing.
A boolean parameter for processing algorithms.
A database schema parameter for processing algorithms, allowing users to select from existing schemas...
A database table name parameter for processing algorithms, allowing users to select from existing dat...
An input feature source (such as vector layers) parameter for processing algorithms.
A vector layer or feature source field parameter for processing algorithms.
A data provider connection parameter for processing algorithms, allowing users to select from availab...
A string parameter for processing algorithms.
Custom exception class for provider connection related exceptions.
Holds data provider key, description, and associated shared library file or function pointer informat...
virtual QgsAbstractProviderConnection * createConnection(const QString &uri, const QVariantMap &configuration)
Creates a new connection from uri and configuration, the newly created connection is not automaticall...
static QgsProviderRegistry * instance(const QString &pluginPath=QString())
Means of accessing canonical single instance.
QgsProviderMetadata * providerMetadata(const QString &providerKey) const
Returns metadata of the provider or nullptr if not found.
unsigned long long qgssize
Qgssize is used instead of size_t, because size_t is stdlib type, unknown by SIP, and it would be har...
Definition qgis.h:6013
The SpatialIndexOptions contains extra options relating to spatial index creation.
QString geometryColumnName
Specifies the name of the geometry column to create the index for.