27.10. Input and output types for Processing Algorithms

Here is the list of input and output types that are supported in Processing with their corresponding alg decorator constants, their name in the modeler designer if exposed.

27.10.1. Input types

Input name

Class

Alg constant

Description

Annotation layer

QgsProcessingParameterAnnotationLayer

alg.ANNOTATION_LAYER

An annotation layer

Authentication Configuration

QgsProcessingParameterAuthConfig

alg.AUTH_CFG

Allows users to select from available authentication configurations or create new authentication configurations

Raster band

QgsProcessingParameterBand

alg.BAND

A band of a raster layer

Boolean

QgsProcessingParameterBoolean

alg.BOOL

A boolean value

Connection Name

QgsProcessingParameterProviderConnection

A selection from available registered connections for a particular data provider

Color

QgsProcessingParameterColor

alg.COLOR

A color

Coordinate Operation

QgsProcessingParameterCoordinateOperation

alg.COORDINATE_OPERATION

A coordinate operation (for CRS transformations)

CRS

QgsProcessingParameterCrs

alg.CRS

A Coordinate Reference System

Database Schema

QgsProcessingParameterDatabaseSchema

alg.DATABASE_SCHEMA

A database schema

Database Table

QgsProcessingParameterDatabaseTable

alg.DATABASE_TABLE

A database table

Datetime

QgsProcessingParameterDateTime

alg.DATETIME

A datetime (or a pure date or time)

Distance

QgsProcessingParameterDistance

alg.DISTANCE

A double numeric parameter for distance values

DXF Layers

QgsProcessingParameterDxfLayers

A list of vector layers to export as DXF file

Enum

QgsProcessingParameterEnum

alg.ENUM

An enumeration, allowing for selection from a set of predefined values

Expression

QgsProcessingParameterExpression

alg.EXPRESSION

An expression

Extent

QgsProcessingParameterExtent

alg.EXTENT

A spatial extent defined by xmin, xmax, ymin, ymax

QgsProcessingParameterField

alg.FIELD

A field in the attribute table of a vector layer

Field Aggregates

QgsProcessingParameterAggregate

A parameter for “aggregate” configurations, which consist of a definition of desired output fields, types, and aggregate used to populate them

Fields Mapper

QgsProcessingParameterFieldMapping

A parameter for “field mapping” configurations, which consist of a definition of desired output fields, types, and expressions used to populate them

File/Folder

QgsProcessingParameterFile

alg.FILE

A filename of an existing file

QgsProcessingParameterFileDestination

alg.FILE_DEST

A filename for a newly created output file

QgsProcessingParameterFolderDestination

alg.FOLDER_DEST

A folder (destination folder)

Geometry

QgsProcessingParameterGeometry

alg.GEOMETRY

A geometry

QgsProcessingParameterNumber.Integer

alg.INT

An integer

Print Layout

QgsProcessingParameterLayout

alg.LAYOUT

A layout

Print Layout Item

QgsProcessingParameterLayoutItem

alg.LAYOUT_ITEM

A layout item

Map Layer

QgsProcessingParameterMapLayer

alg.MAPLAYER

A map layer

Map Theme

QgsProcessingParameterMapTheme

alg.MAP_THEME

A project map theme

Matrix

QgsProcessingParameterMatrix

alg.MATRIX

A matrix

Mesh Dataset Groups

QgsProcessingParameterMeshDatasetGroups

Dataset groups of mesh layer

Mesh Dataset Time

QgsProcessingParameterMeshDatasetTime

Dataset index from a mesh layer by time setting

Mesh Layer

QgsProcessingParameterMeshLayer

alg.MESH_LAYER

A mesh layer

Multiple Input

QgsProcessingParameterMultipleLayers

alg.MULTILAYER

A set of layers

Number

QgsProcessingParameterNumber.Double

alg.NUMBER

A numerical value

Point

QgsProcessingParameterPoint

alg.POINT

A point

Point Cloud Attribute

QgsProcessingParameterPointCloudAttribute

An attribute from a point cloud layer

QgsProcessingParameterPointCloudDestination

alg.POINTCLOUD_LAYER_DEST

A point cloud layer destination parameter, for specifying the destination path for a point cloud layer created by the algorithm

Point Cloud Layer

QgsProcessingParameterPointCloudLayer

alg.POINTCLOUD_LAYER

A point cloud layer

QgsProcessingParameterProviderConnection

alg.PROVIDER_CONNECTION

An available connection for a database provider

Range

QgsProcessingParameterRange

alg.RANGE

A number range

Raster Layer

QgsProcessingParameterRasterLayer

alg.RASTER_LAYER

A raster layer

QgsProcessingParameterRasterDestination

alg.RASTER_LAYER_DEST

A raster layer destination parameter, for specifying the destination path for a raster layer created by the algorithm

Scale

QgsProcessingParameterScale

alg.SCALE

A map scale

QgsProcessingParameterFeatureSink

alg.SINK

A feature sink

TIN Creation Layers

QgsProcessingParameterTinInputLayers

Selection of multiple layers to create a TIN with vertices and/or break lines

Vector Features

QgsProcessingParameterFeatureSource

alg.SOURCE

A feature source

String

QgsProcessingParameterString

alg.STRING

A text string

Vector Layer

QgsProcessingParameterVectorLayer

alg.VECTOR_LAYER

A vector layer

QgsProcessingParameterVectorDestination

alg.VECTOR_LAYER_DEST

A vector layer destination parameter, for specifying the destination path for a vector layer created by the algorithm

Vector Tile Writer Layers

QgsProcessingParameterVectorTileDestination

A vector tile layer destination parameter, for specifying the destination path for a vector tile layer created by the algorithm

27.10.2. Output types

Class

Alg constant

Description

QgsProcessingOutputBoolean

alg.BOOL

A boolean value

QgsProcessingOutputNumber

alg.DISTANCE

A double numeric parameter for distance values

QgsProcessingOutputFile

alg.FILE

A filename of an existing file

QgsProcessingOutputFolder

alg.FOLDER

A folder

QgsProcessingOutputHtml

alg.HTML

HTML

QgsProcessingOutputNumber

alg.INT

A integer

QgsProcessingOutputLayerDefinition

alg.LAYERDEF

A layer definition

QgsProcessingOutputMapLayer

alg.MAPLAYER

A map layer

QgsProcessingOutputMultipleLayers

alg.MULTILAYER

A set of layers

QgsProcessingOutputNumber

alg.NUMBER

A numerical value

QgsProcessingOutputPointCloudLayer

alg.POINTCLOUD_LAYER

A point cloud layer

QgsProcessingOutputRasterLayer

alg.RASTER_LAYER

A raster layer

QgsProcessingOutputString

alg.STRING

A text string

QgsProcessingOutputVectorLayer

alg.VECTOR_LAYER

A vector layer

QgsProcessingOutputVectorTileLayer

A vector tile layer