CREATE DATA TRANSFORMER

Synopsis

CREATE [ OR MODIFY ] DATA TRANSFORMER module.Name
    SOURCE { JSON | XML } 'sample'
{
    { JSLT | XSLT } 'transformation';
    [ { JSLT | XSLT } 'next_step'; ... ]
};

Description

Creates a data transformer that reshapes JSON or XML data through one or more transformation steps before it enters an import mapping or is returned to a caller.

A data transformer applies a pipeline of JSLT (for JSON) or XSLT (for XML) transformations to its input. Steps execute in order; each step’s output becomes the next step’s input.

If OR MODIFY is specified and the transformer already exists, it is updated in place. The document UUID is preserved.

JSLT

JSLT is a JSON transformation language designed for structural reshaping. Common operations:

Field selection: .field
Rename: "newName": .oldName
Arithmetic: .price * .quantity
Conditional: if (.status == "active") "yes" else "no"

Source Sample

The SOURCE clause provides a representative input document. Mendix uses it to validate the transformation at design time. The actual runtime input may differ in values but must match the structure.

Parameters

module.Name: The qualified name of the data transformer.
SOURCE JSON 'sample': A representative JSON input document. Multi-line samples can use $$...$$ quoting.
SOURCE XML 'sample': A representative XML input document.
JSLT 'transformation': A JSLT transformation expression applied to the current input.
XSLT 'transformation': An XSLT stylesheet applied to the current input.

Examples

Single-step JSON flattening

CREATE DATA TRANSFORMER MyModule.FlattenNested
    SOURCE JSON '{"wrapper": {"value": 42, "label": "hello"}}'
{
    JSLT '{"value": .wrapper.value, "label": .wrapper.label}';
};

Multi-line JSLT with $$ quoting

CREATE DATA TRANSFORMER MyModule.WeatherTransform
    SOURCE JSON '{"latitude": 51.9, "longitude": 4.5, "current": {"temperature_2m": 12.8, "wind_speed_10m": 18.3}}'
{
    JSLT $$
{
    "lat":        .latitude,
    "lon":        .longitude,
    "temp":       .current.temperature_2m,
    "wind_speed": .current.wind_speed_10m
}
    $$;
};

Idempotent update

CREATE OR MODIFY DATA TRANSFORMER MyModule.WeatherTransform
    SOURCE JSON '{"latitude": 51.9, "longitude": 4.5, "timezone": "UTC", "current": {"temperature_2m": 12.8}}'
{
    JSLT $$
{
    "lat":      .latitude,
    "lon":      .longitude,
    "timezone": .timezone,
    "temp":     .current.temperature_2m
}
    $$;
};

mxcli Documentation