Class: QgsProjectStorage

class qgis.core.QgsProjectStorage

Bases: sip.wrapper

Abstract interface for project storage - to be implemented by various backends and registered in QgsProjectStorageRegistry.

Methods

filePath

Extracts and returns the file path from a storage backend uri, filesystem-based storage backends should implement this method in order to support relative paths storage.

listProjects

Returns list of all projects for given URI (specific to each storage backend)

readProject

Reads project file content stored in the backend at the specified URI to the given device (could be e.g.

readProjectStorageMetadata

Reads project metadata (e.g.

removeProject

Removes an existing project at the given URI.

renameProject

Rename an existing project at the given URI to a different URI.

showLoadGui

Opens GUI to allow user to select a project to be loaded (GUI specific to this storage type).

showSaveGui

Opens GUI to allow user to select where a project should be saved (GUI specific to this storage type).

type

Unique identifier of the project storage type.

visibleName

Returns human-readable name of the storage.

writeProject

Writes project file content stored in given device (could be e.g.

class Metadata

Bases: sip.wrapper

Metadata associated with a project

New in version 3.2.

lastModified
name
filePath(self, uri: str)str

Extracts and returns the file path from a storage backend uri, filesystem-based storage backends should implement this method in order to support relative paths storage. The default implementation returns an empty string.

New in version 3.8.1.

Parameters

uri (str) –

Return type

str

listProjects(self, uri: str)List[str]

Returns list of all projects for given URI (specific to each storage backend)

Parameters

uri (str) –

Return type

List[str]

readProject(self, uri: str, device: QIODevice, context: QgsReadWriteContext)bool

Reads project file content stored in the backend at the specified URI to the given device (could be e.g. a temporary file or a memory buffer). The device is expected to be empty when passed to readProject() so that the method can write all data to it and then rewind it using seek(0) to make it ready for reading in QgsProject.

Parameters
Return type

bool

readProjectStorageMetadata(self, uri: str)Tuple[bool, QgsProjectStorage.Metadata]

Reads project metadata (e.g. last modified time) if this is supported by the storage implementation. Returns True if the metadata were read with success.

Parameters

uri (str) –

Return type

Tuple[bool, QgsProjectStorage.Metadata]

removeProject(self, uri: str)bool

Removes an existing project at the given URI. Returns True if the removal was successful.

Parameters

uri (str) –

Return type

bool

renameProject(self, uri: str, uriNew: str)bool

Rename an existing project at the given URI to a different URI. Returns True if renaming was successful.

Parameters
  • uri (str) –

  • uriNew (str) –

Return type

bool

showLoadGui(self)str

Opens GUI to allow user to select a project to be loaded (GUI specific to this storage type). Returns project URI if user has picked a project or empty string if the GUI was canceled.

Deprecated since version QGIS: 3.10 - use QgsProjectStorageGuiProvider for GUI-related project storage functionality

Return type

str

showSaveGui(self)str

Opens GUI to allow user to select where a project should be saved (GUI specific to this storage type). Returns project URI if user has picked a destination or empty string if the GUI was canceled.

Deprecated since version QGIS: 3.10 - use QgsProjectStorageGuiProvider for GUI-related project storage functionality

Return type

str

type(self)str

Unique identifier of the project storage type. If type() returns “memory”, all project file names starting with “memory:” will have read/write redirected through that storage implementation.

Return type

str

visibleName(self)str

Returns human-readable name of the storage. Used as the menu item text in QGIS. Empty name indicates that the storage does not implement GUI support (showLoadGui() and showSaveGui()). The name may be translatable and ideally unique as well.

Deprecated since version QGIS: 3.10 - use QgsProjectStorageGuiProvider for GUI-related project storage functionality

Return type

str

writeProject(self, uri: str, device: QIODevice, context: QgsReadWriteContext)bool

Writes project file content stored in given device (could be e.g. a temporary file or a memory buffer) using the backend to the specified URI. The device is expected to contain all project file data and having position at the start of the content when passed to writeProject() so that the method can read all data from it until it reaches its end.

Parameters
Return type

bool