Inputs and Outputs

Parameters description

Process description uses JSON Schema framents te define the inputs and outputs parameters as description in the OGC process description <https://docs.ogc.org/is/18-062r2/18-062r2.html#toc35 document.

This makes the task more complicated for api client to implement generic client since the variability of JSON schema is much more important than what was proposed by the WPS standards, but there is some invrariant rules.

Qjazz-Processes map QgsProcessingParameterDefinition <https://api.qgis.org/api/classQgsProcessingParameterDefinition.html>_ and QgsProcessingOutputDefinition to JSON Schema.

Literals and complex types

Most of the parameters are literals or array of literals types associated with constraints

Most of the time, there will be a format specification as described in additional formats thal will give you hints for the format of the parameter.

Literals will come with allowed values constraint expressed as JSON schema as enumerated values

This will be the case for QgisProcessingParameterEnum or layer names constrained by a source project.

Complex input types will have media types associated with them, allowing the client to select the type of input.

Warning

Input with content media types should always be sent as qualified values.