Holds data provider key, description, and associated shared library file or function pointer information. More...

#include <qgsprovidermetadata.h>

Inheritance diagram for QgsProviderMetadata:

Public Types
typedef std::function< QgsDataProvider *(const QString &, const QgsDataProvider::ProviderOptions &, QgsDataProvider::ReadFlags &) >	CreateDataProviderFunction
	Typedef for data provider creation function.

typedef QFlags< ProviderCapability >	ProviderCapabilities

enum	ProviderCapability { FileBasedUris = 1 << 0 , SaveLayerMetadata = 1 << 1 , ParallelCreateProvider = 1 << 2 }
	Provider capabilities. More...

typedef QFlags< ProviderMetadataCapability >	ProviderMetadataCapabilities

enum	ProviderMetadataCapability { PriorityForUri = 1 << 0 , LayerTypesForUri = 1 << 1 , QuerySublayers = 1 << 2 , CreateDatabase = 1 << 3 }
	Indicates capabilities of the provider metadata implementation. More...

Signals
void	connectionChanged (const QString &name)
	Emitted when the connection with the specified name is changed, e.g.

void	connectionCreated (const QString &name)
	Emitted when a connection with the specified name is created.

void	connectionDeleted (const QString &name)
	Emitted when the connection with the specified name was deleted.

Public Member Functions
Q_DECL_DEPRECATED	QgsProviderMetadata (const QString &key, const QString &description, const QgsProviderMetadata::CreateDataProviderFunction &createFunc)
	Metadata for provider with direct provider creation function pointer, where no library is involved.

	QgsProviderMetadata (const QString &key, const QString &description, const QString &library=QString())
	Constructor for provider metadata.

virtual	~QgsProviderMetadata ()
	dtor

virtual QString	absoluteToRelativeUri (const QString &uri, const QgsReadWriteContext &context) const
	Converts absolute path(s) to relative path(s) in the given provider-specific URI.

virtual QgsProviderMetadata::ProviderMetadataCapabilities	capabilities () const
	Returns the provider metadata capabilities.

virtual void	cleanupProvider ()
	Cleanup the provider.

virtual QMap< QString, QgsAbstractProviderConnection * >	connections (bool cached=true)
	Returns a dictionary of stored provider connections, the dictionary key is the connection identifier.

template<typename T >
QMap< QString, T * >	connections (bool cached=true)
	Returns a dictionary of provider connections of the specified type T, the dictionary key is the connection identifier.

virtual QgsAbstractProviderConnection *	createConnection (const QString &name)
	Creates a new connection by loading the connection with the given name from the settings.

virtual QgsAbstractProviderConnection *	createConnection (const QString &uri, const QVariantMap &configuration)
	Creates a new connection from uri and configuration, the newly created connection is not automatically stored in the settings, call saveConnection() to save it.

virtual bool	createDatabase (const QString &uri, QString &errorMessage)
	Creates a new empty database at the specified uri.

virtual bool	createDb (const QString &dbPath, QString &errCause)
	Creates database by the provider on the path.

virtual Qgis::VectorExportResult	createEmptyLayer (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.

Q_DECL_DEPRECATED CreateDataProviderFunction	createFunction () const
	Returns a pointer to the direct provider creation function, if supported by the provider.

virtual bool	createMeshData (const QgsMesh &mesh, const QString &fileName, const QString &driverName, const QgsCoordinateReferenceSystem &crs, const QMap< QString, QString > &metadata=QMap< QString, QString >()) const
	Creates mesh data source from a file name fileName and a driver driverName, that is the mesh frame stored in file, memory or with other way (depending of the provider) Since QGIS 3.38 the optional metadata argument can be used to pass metadata to the provider.

virtual bool	createMeshData (const QgsMesh &mesh, const QString &uri, const QgsCoordinateReferenceSystem &crs, const QMap< QString, QString > &metadata=QMap< QString, QString >()) const
	Creates mesh data source from an uri, that is the mesh frame stored in file, memory or with other way (depending of the provider) Since QGIS 3.38 the optional metadata argument can be used to pass metadata to the provider.

virtual QgsDataProvider *	createProvider (const QString &uri, const QgsDataProvider::ProviderOptions &options, QgsDataProvider::ReadFlags flags=QgsDataProvider::ReadFlags())
	Class factory to return a pointer to a newly created QgsDataProvider object.

virtual QgsRasterDataProvider *	createRasterDataProvider (const QString &uri, const QString &format, int nBands, Qgis::DataType type, int width, int height, double *geoTransform, const QgsCoordinateReferenceSystem &crs, const QStringList &createOptions=QStringList())
	Creates a new instance of the raster data provider.

virtual QgsTransaction *	createTransaction (const QString &connString)
	Returns new instance of transaction.

virtual QList< QgsDataItemProvider * >	dataItemProviders () const
	Returns data item providers.

QMap< QString, QgsAbstractDatabaseProviderConnection * >	dbConnections (bool cached=true)
	Returns a dictionary of database provider connections, the dictionary key is the connection identifier.

virtual QVariantMap	decodeUri (const QString &uri) const
	Breaks a provider data source URI into its component paths (e.g.

virtual void	deleteConnection (const QString &name)
	Removes the connection with the given name from the settings.

virtual bool	deleteStyleById (const QString &uri, const QString &styleId, QString &errCause)
	Deletes a layer style defined by styleId.

QString	description () const
	This returns descriptive text for the provider.

virtual QString	encodeUri (const QVariantMap &parts) const
	Reassembles a provider data source URI from its component paths (e.g.

virtual QString	filters (Qgis::FileFilterType type)
	Builds the list of file filter strings (supported formats)

QgsAbstractProviderConnection *	findConnection (const QString &name, bool cached=true)
	Searches and returns a (possibly NULL) connection from the stored provider connections.

virtual QString	getStyleById (const QString &uri, const QString &styleId, QString &errCause)
	Gets a layer style defined by uri.

virtual QIcon	icon () const
	Returns an icon representing the provider.

virtual void	initProvider ()
	Initialize the provider.

QString	key () const
	This returns the unique key associated with the provider.

Q_DECL_DEPRECATED QString	library () const
	This returns the library file name.

virtual int	listStyles (const QString &uri, QStringList &ids, QStringList &names, QStringList &descriptions, QString &errCause)
	Lists stored layer styles in the provider defined by uri.

virtual QString	loadStoredStyle (const QString &uri, QString &styleName, QString &errCause)
	Loads a layer style from the provider storage, reporting its name.

virtual QString	loadStyle (const QString &uri, QString &errCause)
	Loads a layer style defined by uri.

virtual QList< QgsMeshDriverMetadata >	meshDriversMetadata ()
	Builds the list of available mesh drivers metadata.

virtual int	priorityForUri (const QString &uri) const
	Returns an integer representing the priority which this provider should have when opening a dataset with the specified uri.

virtual QgsProviderMetadata::ProviderCapabilities	providerCapabilities () const
	Returns the provider's capabilities.

virtual QList< QPair< QString, QString > >	pyramidResamplingMethods ()
	Returns pyramid resampling methods available for provider.

virtual QList< QgsProviderSublayerDetails >	querySublayers (const QString &uri, Qgis::SublayerQueryFlags flags=Qgis::SublayerQueryFlags(), QgsFeedback *feedback=nullptr) const
	Queries the specified uri and returns a list of any valid sublayers found in the dataset which can be handled by this provider.

virtual QString	relativeToAbsoluteUri (const QString &uri, const QgsReadWriteContext &context) const
	Converts relative path(s) to absolute path(s) in the given provider-specific URI.

virtual void	saveConnection (const QgsAbstractProviderConnection *connection, const QString &name)
	Stores the connection in the settings.

virtual bool	saveLayerMetadata (const QString &uri, const QgsLayerMetadata &metadata, QString &errorMessage)
	Saves metadata to the layer corresponding to the specified uri.

virtual bool	saveStyle (const QString &uri, const QString &qmlStyle, const QString &sldStyle, const QString &styleName, const QString &styleDescription, const QString &uiFileContent, bool useAsDefault, QString &errCause)
	Saves a layer style to provider.

virtual QStringList	sidecarFilesForUri (const QString &uri) const
	Given a uri, returns any sidecar files which are associated with the URI and this provider.

virtual bool	styleExists (const QString &uri, const QString &styleId, QString &errorCause)
	Returns `true` if a layer style with the specified styleId exists in the provider defined by uri.

virtual QString	suggestGroupNameForUri (const QString &uri) const
	Returns a name that can be used as a group name for sublayers retrieved from the specified uri.

virtual QList< Qgis::LayerType >	supportedLayerTypes () const
	Returns a list of the map layer types supported by the provider.

virtual bool	uriIsBlocklisted (const QString &uri) const
	Returns `true` if the specified uri is known by this provider to be something which should be blocklisted from the QGIS interface, e.g.

virtual QList< Qgis::LayerType >	validLayerTypesForUri (const QString &uri) const
	Returns a list of valid layer types which the provider can be used with when opening the specified uri.

Static Public Member Functions
static bool	boolParameter (const QVariantMap &uri, const QString &parameter, bool defaultValue=false)
	Returns the parameter value in the uri as a bool.

static void	setBoolParameter (QVariantMap &uri, const QString &parameter, const QVariant &value)
	Sets the value into the uri parameter as a bool.

Detailed Description

Holds data provider key, description, and associated shared library file or function pointer information.

Provider metadata refers either to providers which are loaded via libraries or which are native providers that are included in the core QGIS installation and accessed through function pointers.

For library based providers, the metadata class is used in a lazy load implementation in QgsProviderRegistry. To save memory, data providers are only actually loaded via QLibrary calls if they're to be used. (Though they're all iteratively loaded once to get their metadata information, and then unloaded when the QgsProviderRegistry is created.) QgsProviderMetadata supplies enough information to be able to later load the associated shared library object.

Definition at line 176 of file qgsprovidermetadata.h.

Member Typedef Documentation

◆ CreateDataProviderFunction

typedef std::function< QgsDataProvider*( const QString &, const QgsDataProvider::ProviderOptions &, QgsDataProvider::ReadFlags & ) > QgsProviderMetadata::CreateDataProviderFunction

Typedef for data provider creation function.

Definition at line 212 of file qgsprovidermetadata.h.

◆ ProviderCapabilities

typedef QFlags< ProviderCapability > QgsProviderMetadata::ProviderCapabilities

Definition at line 207 of file qgsprovidermetadata.h.

◆ ProviderMetadataCapabilities

typedef QFlags< ProviderMetadataCapability > QgsProviderMetadata::ProviderMetadataCapabilities

Definition at line 194 of file qgsprovidermetadata.h.

Member Enumeration Documentation

◆ ProviderCapability

enum QgsProviderMetadata::ProviderCapability

Provider capabilities.

Since: QGIS 3.18.1

Enumerator
FileBasedUris	Indicates that the provider can utilize URIs which are based on paths to files (as opposed to database or internet paths)
SaveLayerMetadata	Indicates that the provider supports saving native layer metadata (since QGIS 3.20)
ParallelCreateProvider	Indicates that the provider supports parallel creation, that is, can be created on another thread than the main thread (since QGIS 3.32)

Definition at line 201 of file qgsprovidermetadata.h.

◆ ProviderMetadataCapability

enum QgsProviderMetadata::ProviderMetadataCapability

Indicates capabilities of the provider metadata implementation.

Since: QGIS 3.18

Enumerator
PriorityForUri	Indicates that the metadata can calculate a priority for a URI.
LayerTypesForUri	Indicates that the metadata can determine valid layer types for a URI.
QuerySublayers	Indicates that the metadata can query sublayers for a URI (since QGIS 3.22)
CreateDatabase	Indicates that the metadata can create new empty databases (since QGIS 3.28)

Definition at line 187 of file qgsprovidermetadata.h.

Constructor & Destructor Documentation

◆ QgsProviderMetadata() [1/2]

QgsProviderMetadata::QgsProviderMetadata	(	const QString &	key,
		const QString &	description,
		const QString &	library = `QString()`
	)

Constructor for provider metadata.

Parameters

key	provider key
description	provider description
library	plugin library file name (empty if the provider is not loaded from a library)

Definition at line 26 of file qgsprovidermetadata.cpp.

◆ QgsProviderMetadata() [2/2]

QgsProviderMetadata::QgsProviderMetadata	(	const QString &	key,
		const QString &	description,
		const QgsProviderMetadata::CreateDataProviderFunction &	createFunc
	)

Metadata for provider with direct provider creation function pointer, where no library is involved.

Deprecated:: QGIS 3.10

Definition at line 34 of file qgsprovidermetadata.cpp.

◆ ~QgsProviderMetadata()

QgsProviderMetadata::~QgsProviderMetadata ( )

virtual

dtor

Definition at line 40 of file qgsprovidermetadata.cpp.

Member Function Documentation

◆ absoluteToRelativeUri()

QString QgsProviderMetadata::absoluteToRelativeUri	(	const QString &	uri,
		const QgsReadWriteContext &	context
	)		const

virtual

Converts absolute path(s) to relative path(s) in the given provider-specific URI.

and returns modified URI according to the context object's configuration. This is commonly used when writing project files. If a provider does not work with paths, unmodified URI will be returned.

Returns: modified URI with relative path(s)

Note: this function may not be supported by all providers. The default implementation uses QgsPathResolver::writePath() on the whole URI.

See also: relativeToAbsoluteUri()

Since: QGIS 3.30

Definition at line 190 of file qgsprovidermetadata.cpp.

◆ boolParameter()

bool QgsProviderMetadata::boolParameter	(	const QVariantMap &	uri,
		const QString &	parameter,
		bool	defaultValue = `false`
	)

static

Returns the parameter value in the uri as a bool.

eg. "yes" value will be returned as true, 0 will be returned as false

Since: QGIS 3.14

Definition at line 162 of file qgsprovidermetadata.cpp.

◆ capabilities()

QgsProviderMetadata::ProviderMetadataCapabilities QgsProviderMetadata::capabilities ( ) const

virtual

Returns the provider metadata capabilities.

Since: QGIS 3.18

Definition at line 60 of file qgsprovidermetadata.cpp.

◆ cleanupProvider()

void QgsProviderMetadata::cleanupProvider ( )

virtual

Cleanup the provider.

Since: QGIS 3.10

Definition at line 95 of file qgsprovidermetadata.cpp.

◆ connectionChanged

void QgsProviderMetadata::connectionChanged ( const QString & name )

signal

Emitted when the connection with the specified name is changed, e.g.

the settings relating to the connection have been updated.

Note: Only providers which implement the connection handling API will emit this signal.

Since: QGIS 3.14

◆ connectionCreated

void QgsProviderMetadata::connectionCreated ( const QString & name )

signal

Emitted when a connection with the specified name is created.

Note: Only providers which implement the connection handling API will emit this signal.

Since: QGIS 3.14

◆ connectionDeleted

void QgsProviderMetadata::connectionDeleted ( const QString & name )

signal

Emitted when the connection with the specified name was deleted.

Note: Only providers which implement the connection handling API will emit this signal.

Since: QGIS 3.14

◆ connections() [1/2]

QMap< QString, QgsAbstractProviderConnection * > QgsProviderMetadata::connections ( bool cached = true )

virtual

Returns a dictionary of stored provider connections, the dictionary key is the connection identifier.

Ownership is not transferred. Raises a QgsProviderConnectionException if any errors are encountered.

Parameters

cached if false connections will be re-read from the settings

Exceptions

QgsProviderConnectionException

Since: QGIS 3.10

Definition at line 313 of file qgsprovidermetadata.cpp.

◆ connections() [2/2]

template<typename T >

QMap< QString, T * > QgsProviderMetadata::connections ( bool cached = true )

Returns a dictionary of provider connections of the specified type T, the dictionary key is the connection identifier.

Parameters

cached if false connections will be re-read from the settings

Note: not available in Python bindings

Since: QGIS 3.10

Definition at line 380 of file qgsprovidermetadata.cpp.

◆ createConnection() [1/2]

QgsAbstractProviderConnection * QgsProviderMetadata::createConnection ( const QString & name )

virtual

Creates a new connection by loading the connection with the given name from the settings.

Ownership is transferred to the caller.

Exceptions

QgsProviderConnectionException

See also: findConnection()

Definition at line 338 of file qgsprovidermetadata.cpp.

◆ createConnection() [2/2]

QgsAbstractProviderConnection * QgsProviderMetadata::createConnection	(	const QString &	uri,
		const QVariantMap &	configuration
	)

virtual

Creates a new connection from uri and configuration, the newly created connection is not automatically stored in the settings, call saveConnection() to save it.

Ownership is transferred to the caller.

Exceptions

QgsProviderConnectionException

See also: saveConnection()

Since: QGIS 3.10

Definition at line 345 of file qgsprovidermetadata.cpp.

◆ createDatabase()

bool QgsProviderMetadata::createDatabase	(	const QString &	uri,
		QString &	errorMessage
	)

virtual

Creates a new empty database at the specified uri.

This method can be used for supported providers to construct a new empty database. For instance, the OGR provider metadata createDatabase() method can be used to create new empty GeoPackage or FileGeodatabase databases.

Parameters

uri	destination URI for newly created database.
errorMessage	will be set to a descriptive error message if the database could not be successfully created.

Returns: true if the database was successfully created

Note: This method is only supported by providers which return the QgsProviderMetadata::ProviderMetadataCapability::CreateDatabase capability.

Since: QGIS 3.28

Definition at line 209 of file qgsprovidermetadata.cpp.

◆ createDb()

bool QgsProviderMetadata::createDb	(	const QString &	dbPath,
		QString &	errCause
	)

virtual

Creates database by the provider on the path.

Since: QGIS 3.10

Definition at line 302 of file qgsprovidermetadata.cpp.

◆ createEmptyLayer()

Qgis::VectorExportResult QgsProviderMetadata::createEmptyLayer	(	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
	)

virtual

Creates new empty vector layer.

Note: not available in Python bindings

Since: QGIS 3.10

Definition at line 200 of file qgsprovidermetadata.cpp.

◆ createFunction()

QgsProviderMetadata::CreateDataProviderFunction QgsProviderMetadata::createFunction ( ) const

Returns a pointer to the direct provider creation function, if supported by the provider.

Note: not available in Python bindings

Deprecated:: QGIS 3.10

Definition at line 85 of file qgsprovidermetadata.cpp.

◆ createMeshData() [1/2]

bool QgsProviderMetadata::createMeshData	(	const QgsMesh &	mesh,
		const QString &	fileName,
		const QString &	driverName,
		const QgsCoordinateReferenceSystem &	crs,
		const QMap< QString, QString > &	metadata = `QMap<QString, QString>()`
	)		const

virtual

Creates mesh data source from a file name fileName and a driver driverName, that is the mesh frame stored in file, memory or with other way (depending of the provider) Since QGIS 3.38 the optional metadata argument can be used to pass metadata to the provider.

Since: QGIS 3.16

Definition at line 225 of file qgsprovidermetadata.cpp.

◆ createMeshData() [2/2]

bool QgsProviderMetadata::createMeshData	(	const QgsMesh &	mesh,
		const QString &	uri,
		const QgsCoordinateReferenceSystem &	crs,
		const QMap< QString, QString > &	metadata = `QMap<QString, QString>()`
	)		const

virtual

Creates mesh data source from an uri, that is the mesh frame stored in file, memory or with other way (depending of the provider) Since QGIS 3.38 the optional metadata argument can be used to pass metadata to the provider.

Since: QGIS 3.22

Definition at line 234 of file qgsprovidermetadata.cpp.

◆ createProvider()

QgsDataProvider * QgsProviderMetadata::createProvider	(	const QString &	uri,
		const QgsDataProvider::ProviderOptions &	options,
		QgsDataProvider::ReadFlags	flags = `QgsDataProvider::ReadFlags()`
	)

virtual

Class factory to return a pointer to a newly created QgsDataProvider object.

Parameters

uri	the datasource uri
options	creation options
flags	creation flags, sing QGIS 3.16

Since: QGIS 3.10

Definition at line 135 of file qgsprovidermetadata.cpp.

◆ createRasterDataProvider()

QgsRasterDataProvider * QgsProviderMetadata::createRasterDataProvider	(	const QString &	uri,
		const QString &	format,
		int	nBands,
		Qgis::DataType	type,
		int	width,
		int	height,
		double *	geoTransform,
		const QgsCoordinateReferenceSystem &	crs,
		const QStringList &	createOptions = `QStringList()`
	)

virtual

Creates a new instance of the raster data provider.

Since: QGIS 3.10

Definition at line 215 of file qgsprovidermetadata.cpp.

◆ createTransaction()

QgsTransaction * QgsProviderMetadata::createTransaction ( const QString & connString )

virtual

Returns new instance of transaction.

Ownership is transferred to the caller

Since: QGIS 3.10

Definition at line 308 of file qgsprovidermetadata.cpp.

◆ dataItemProviders()

QList< QgsDataItemProvider * > QgsProviderMetadata::dataItemProviders ( ) const

virtual

Returns data item providers.

Caller is responsible for ownership of the item providers

See also: QgsProviderGuiMetadata::dataItemGuiProviders()

Note: Ownership of created data item providers is passed to the caller.

Since: QGIS 3.10

Definition at line 247 of file qgsprovidermetadata.cpp.

◆ dbConnections()

QMap< QString, QgsAbstractDatabaseProviderConnection * > QgsProviderMetadata::dbConnections ( bool cached = true )

Returns a dictionary of database provider connections, the dictionary key is the connection identifier.

Ownership is not transferred. Raises a QgsProviderConnectionException if any errors are encountered.

Parameters

cached if false connections will be re-read from the settings

Exceptions

QgsProviderConnectionException

Since: QGIS 3.10

Definition at line 319 of file qgsprovidermetadata.cpp.

◆ decodeUri()

QVariantMap QgsProviderMetadata::decodeUri ( const QString & uri ) const

virtual

Breaks a provider data source URI into its component paths (e.g.

file path, layer name).

Parameters

uri	uri string

Returns: map containing components. Standard components may include:

"path": file path
"layerName"
"url": base URL, for online services
"referer": referrer string, for HTTP requests
"host": hostname, for database services
"bounds": hardcoded layer bounds (as a QgsRectangle)
"crs": CRS definition
"authcfg": authentication configuration ID

Note: this function may not be supported by all providers, an empty map will be returned in such case

Since: QGIS 3.10

Definition at line 180 of file qgsprovidermetadata.cpp.

◆ deleteConnection()

void QgsProviderMetadata::deleteConnection ( const QString & name )

virtual

Removes the connection with the given name from the settings.

Raises a QgsProviderConnectionException if any errors are encountered.

Exceptions

QgsProviderConnectionException

Since: QGIS 3.10

Definition at line 352 of file qgsprovidermetadata.cpp.

◆ deleteStyleById()

bool QgsProviderMetadata::deleteStyleById	(	const QString &	uri,
		const QString &	styleId,
		QString &	errCause
	)

virtual

Deletes a layer style defined by styleId.

Since: QGIS 3.10

Definition at line 272 of file qgsprovidermetadata.cpp.

◆ description()

QString QgsProviderMetadata::description ( ) const

This returns descriptive text for the provider.

This is used to provide a descriptive list of available data providers.

Definition at line 50 of file qgsprovidermetadata.cpp.

◆ encodeUri()

QString QgsProviderMetadata::encodeUri ( const QVariantMap & parts ) const

virtual

Reassembles a provider data source URI from its component paths (e.g.

file path, layer name).

Parameters

parts parts as returned by decodeUri

Returns: datasource uri string

Note: this function may not be supported by all providers, an empty string will be returned in such case

See also: decodeUri()

Since: QGIS 3.12

Definition at line 185 of file qgsprovidermetadata.cpp.

◆ filters()

QString QgsProviderMetadata::filters ( Qgis::FileFilterType type )

virtual

Builds the list of file filter strings (supported formats)

Suitable for use in a QFileDialog::getOpenFileNames() call.

Since: QGIS 3.10

Definition at line 100 of file qgsprovidermetadata.cpp.

◆ findConnection()

QgsAbstractProviderConnection * QgsProviderMetadata::findConnection	(	const QString &	name,
		bool	cached = `true`
	)

Searches and returns a (possibly NULL) connection from the stored provider connections.

Ownership is not transferred. Raises a QgsProviderConnectionException if any errors are encountered.

Parameters

name	the connection name
cached	if `false` connections will be re-read from the settings

Exceptions

QgsProviderConnectionException

Since: QGIS 3.10

Definition at line 324 of file qgsprovidermetadata.cpp.

◆ getStyleById()

QString QgsProviderMetadata::getStyleById	(	const QString &	uri,
		const QString &	styleId,
		QString &	errCause
	)

virtual

Gets a layer style defined by uri.

See also: styleExists()

Since: QGIS 3.10

Definition at line 266 of file qgsprovidermetadata.cpp.

◆ icon()

QIcon QgsProviderMetadata::icon ( ) const

virtual

Returns an icon representing the provider.

Since: QGIS 3.26

Definition at line 55 of file qgsprovidermetadata.cpp.

◆ initProvider()

void QgsProviderMetadata::initProvider ( )

virtual

Initialize the provider.

Since: QGIS 3.10

Definition at line 90 of file qgsprovidermetadata.cpp.

◆ key()

QString QgsProviderMetadata::key ( ) const

This returns the unique key associated with the provider.

This key string is used for the associative container in QgsProviderRegistry

Definition at line 45 of file qgsprovidermetadata.cpp.

◆ library()

QString QgsProviderMetadata::library ( ) const

This returns the library file name.

This is used to QLibrary calls to load the data provider (only for dynamically loaded libraries)

Deprecated:: QGIS 3.10 - providers may not need to be loaded from a library (empty string returned)

Definition at line 75 of file qgsprovidermetadata.cpp.

◆ listStyles()

int QgsProviderMetadata::listStyles	(	const QString &	uri,
		QStringList &	ids,
		QStringList &	names,
		QStringList &	descriptions,
		QString &	errCause
	)

virtual

Lists stored layer styles in the provider defined by uri.

Returns: -1 if not implemented by provider, otherwise number of styles stored

Since: QGIS 3.10

Definition at line 252 of file qgsprovidermetadata.cpp.

◆ loadStoredStyle()

QString QgsProviderMetadata::loadStoredStyle	(	const QString &	uri,
		QString &	styleName,
		QString &	errCause
	)

virtual

Loads a layer style from the provider storage, reporting its name.

Parameters

uri	data source uri
styleName	the name of the style if available, empty otherwise
errCause	report errors

Returns: the style QML (XML)

Since: QGIS 3.30

Definition at line 291 of file qgsprovidermetadata.cpp.

◆ loadStyle()

QString QgsProviderMetadata::loadStyle	(	const QString &	uri,
		QString &	errCause
	)

virtual

Loads a layer style defined by uri.

Since: QGIS 3.10

Definition at line 285 of file qgsprovidermetadata.cpp.

◆ meshDriversMetadata()

QList< QgsMeshDriverMetadata > QgsProviderMetadata::meshDriversMetadata ( )

virtual

Builds the list of available mesh drivers metadata.

Since: QGIS 3.12

Definition at line 105 of file qgsprovidermetadata.cpp.

◆ priorityForUri()

int QgsProviderMetadata::priorityForUri ( const QString & uri ) const

virtual

Returns an integer representing the priority which this provider should have when opening a dataset with the specified uri.

A larger priority means that the provider should be selected over others with a lower priority for the same URI.

The default implementation returns 0 for all URIs.

Warning: Not all providers implement this functionality. Check whether capabilities() returns the ProviderMetadataCapability::PriorityForUri to determine whether a specific provider metadata object supports this method.

Since: QGIS 3.18

Definition at line 110 of file qgsprovidermetadata.cpp.

◆ providerCapabilities()

QgsProviderMetadata::ProviderCapabilities QgsProviderMetadata::providerCapabilities ( ) const

virtual

Returns the provider's capabilities.

Since: QGIS 3.18.1

Definition at line 65 of file qgsprovidermetadata.cpp.

◆ pyramidResamplingMethods()

QList< QPair< QString, QString > > QgsProviderMetadata::pyramidResamplingMethods ( )

virtual

Returns pyramid resampling methods available for provider.

Since: QGIS 3.10

Definition at line 242 of file qgsprovidermetadata.cpp.

◆ querySublayers()

QList< QgsProviderSublayerDetails > QgsProviderMetadata::querySublayers	(	const QString &	uri,
		Qgis::SublayerQueryFlags	flags = `Qgis::SublayerQueryFlags()`,
		QgsFeedback *	feedback = `nullptr`
	)		const

virtual

Queries the specified uri and returns a list of any valid sublayers found in the dataset which can be handled by this provider.

The optional flags argument can be used to control the behavior of the query.

The optional feedback argument can be used to provide cancellation support for long-running queries.

Note: Providers which implement this method should always return a list of sublayer details for any valid, even if the uri only relates to a single layer. Returning a non-empty list indicates that the provider is able to load at least one layer using the uri, and is used to collate a combined layer of all providers which support the URI (e.g. in the case that a URI may be readable by multiple different providers).

Since: QGIS 3.22

Definition at line 130 of file qgsprovidermetadata.cpp.

◆ relativeToAbsoluteUri()

QString QgsProviderMetadata::relativeToAbsoluteUri	(	const QString &	uri,
		const QgsReadWriteContext &	context
	)		const

virtual

Converts relative path(s) to absolute path(s) in the given provider-specific URI.

and returns modified URI according to the context object's configuration. This is commonly used when reading project files. If a provider does not work with paths, unmodified URI will be returned.

Returns: modified URI with absolute path(s)

Note: this function may not be supported by all providers. The default implementation uses QgsPathResolver::readPath() on the whole URI.

See also: absoluteToRelativeUri()

Since: QGIS 3.30

Definition at line 195 of file qgsprovidermetadata.cpp.

◆ saveConnection()

void QgsProviderMetadata::saveConnection	(	const QgsAbstractProviderConnection *	connection,
		const QString &	name
	)

virtual

Stores the connection in the settings.

Parameters

connection	the connection to be stored in the settings
name	the name under which the connection will be stored

Exceptions

QgsProviderConnectionException

Since: QGIS 3.10

Definition at line 358 of file qgsprovidermetadata.cpp.

◆ saveLayerMetadata()

bool QgsProviderMetadata::saveLayerMetadata	(	const QString &	uri,
		const QgsLayerMetadata &	metadata,
		QString &	errorMessage
	)

virtual

Saves metadata to the layer corresponding to the specified uri.

Parameters

uri	uri of layer to store metadata for
metadata	layer metadata
errorMessage	descriptive string of error if encountered

Returns: true if the metadata was successfully saved.

Exceptions

QgsNotSupportedException if the provider does not support saving layer metadata for the specified uri.

Since: QGIS 3.20

Definition at line 297 of file qgsprovidermetadata.cpp.

◆ saveStyle()

bool QgsProviderMetadata::saveStyle	(	const QString &	uri,
		const QString &	qmlStyle,
		const QString &	sldStyle,
		const QString &	styleName,
		const QString &	styleDescription,
		const QString &	uiFileContent,
		bool	useAsDefault,
		QString &	errCause
	)

virtual

Saves a layer style to provider.

Note: Prior to QGIS 3.24, this method would show a message box warning when a style with the same styleName already existed to confirm replacing the style with the user. Since 3.24, calling this method will ALWAYS overwrite any existing style with the same name. Use styleExists() to test in advance if a style already exists and handle this appropriately in your client code.

Since: QGIS 3.10

Definition at line 278 of file qgsprovidermetadata.cpp.

◆ setBoolParameter()

void QgsProviderMetadata::setBoolParameter	(	QVariantMap &	uri,
		const QString &	parameter,
		const QVariant &	value
	)

static

Sets the value into the uri parameter as a bool.

eg. "yes" value will be saved as true, 0 will be saved as false

Since: QGIS 3.14

Definition at line 146 of file qgsprovidermetadata.cpp.

◆ sidecarFilesForUri()

QStringList QgsProviderMetadata::sidecarFilesForUri ( const QString & uri ) const

virtual

Given a uri, returns any sidecar files which are associated with the URI and this provider.

In this context a sidecar file is defined as a file which shares the same base filename as a dataset, but which differs in file extension. It defines the list of additional files which must be renamed or deleted alongside the main file associated with the dataset in order to completely rename/delete the dataset.

For instance, the OGR provider would return the corresponding .dbf, .idx, etc files for a uri pointing at a .shp file.

Implementations should files any files which MAY exist for the URI, and it is up to the caller to filter these to only existing files if required.

Note: Some file formats consist of a set of static file names, such as ESRI aigrid datasets which consist of a folder with files with the names "hdr.adf", "prj.adf", etc. These statically named files are NOT considered as sidecar files.

Since: QGIS 3.22

Definition at line 125 of file qgsprovidermetadata.cpp.

◆ styleExists()

bool QgsProviderMetadata::styleExists	(	const QString &	uri,
		const QString &	styleId,
		QString &	errorCause
	)

virtual

Returns true if a layer style with the specified styleId exists in the provider defined by uri.

Parameters

uri	provider URI
styleId	style ID to test for
errorCause	will be set to a descriptive error message, if an error occurs while checking if the style exists

Returns: true if the layer style already exists

See also: getStyleById()

Since: QGIS 3.24

Definition at line 260 of file qgsprovidermetadata.cpp.

◆ suggestGroupNameForUri()

QString QgsProviderMetadata::suggestGroupNameForUri ( const QString & uri ) const

virtual

Returns a name that can be used as a group name for sublayers retrieved from the specified uri.

The default implementation returns an empty string.

Since: QGIS 3.30

Definition at line 80 of file qgsprovidermetadata.cpp.

◆ supportedLayerTypes()

QList< Qgis::LayerType > QgsProviderMetadata::supportedLayerTypes ( ) const

virtual

Returns a list of the map layer types supported by the provider.

Since: QGIS 3.26

Definition at line 70 of file qgsprovidermetadata.cpp.

◆ uriIsBlocklisted()

bool QgsProviderMetadata::uriIsBlocklisted ( const QString & uri ) const

virtual

Returns true if the specified uri is known by this provider to be something which should be blocklisted from the QGIS interface, e.g.

an internal detail only.

Specifically, this method can be utilized by the browser panel to hide noisy internal details by returning true for URIs which are known to be sidecar files only, such as ".aux.xml" files or ".shp.xml" files, or the "ept-build.json" files which sit alongside Entwine "ept.json" point cloud sources.

The default method returns false for all URIs.

Warning: Returning true from an implementation of this method indicates that ALL providers should ignore the specified uri, not just the provider associated with this metadata!

Since: QGIS 3.18

Definition at line 120 of file qgsprovidermetadata.cpp.

◆ validLayerTypesForUri()

QList< Qgis::LayerType > QgsProviderMetadata::validLayerTypesForUri ( const QString & uri ) const

virtual

Returns a list of valid layer types which the provider can be used with when opening the specified uri.

Warning: Not all providers implement this functionality. Check whether capabilities() returns the ProviderMetadataCapability::LayerTypesForUri to determine whether a specific provider metadata object supports this method.

Since: QGIS 3.18

Definition at line 115 of file qgsprovidermetadata.cpp.

The documentation for this class was generated from the following files:

/home/fischer/src/qgis-3.38/src/core/providers/qgsprovidermetadata.h
/home/fischer/src/qgis-3.38/src/core/providers/qgsprovidermetadata.cpp

Public Types

Signals

Public Member Functions

Static Public Member Functions

Detailed Description

Member Typedef Documentation

◆ CreateDataProviderFunction

◆ ProviderCapabilities

◆ ProviderMetadataCapabilities

Member Enumeration Documentation

◆ ProviderCapability

◆ ProviderMetadataCapability

Constructor & Destructor Documentation

◆ QgsProviderMetadata() [1/2]

◆ QgsProviderMetadata() [2/2]

◆ ~QgsProviderMetadata()

Member Function Documentation

◆ absoluteToRelativeUri()

◆ boolParameter()

◆ capabilities()

◆ cleanupProvider()

◆ connectionChanged

◆ connectionCreated

◆ connectionDeleted

◆ connections() [1/2]

◆ connections() [2/2]

◆ createConnection() [1/2]

◆ createConnection() [2/2]

◆ createDatabase()

◆ createDb()

◆ createEmptyLayer()

◆ createFunction()

◆ createMeshData() [1/2]

◆ createMeshData() [2/2]

◆ createProvider()

◆ createRasterDataProvider()

◆ createTransaction()

◆ dataItemProviders()

◆ dbConnections()

◆ decodeUri()

◆ deleteConnection()

◆ deleteStyleById()

◆ description()

◆ encodeUri()

◆ filters()

◆ findConnection()

◆ getStyleById()

◆ icon()

◆ initProvider()

◆ key()

◆ library()

◆ listStyles()

◆ loadStoredStyle()

◆ loadStyle()

◆ meshDriversMetadata()

◆ priorityForUri()

◆ providerCapabilities()

◆ pyramidResamplingMethods()

◆ querySublayers()

◆ relativeToAbsoluteUri()

◆ saveConnection()

◆ saveLayerMetadata()

◆ saveStyle()

◆ setBoolParameter()

◆ sidecarFilesForUri()

◆ styleExists()

◆ suggestGroupNameForUri()

◆ supportedLayerTypes()

◆ uriIsBlocklisted()

◆ validLayerTypesForUri()