Function validation
Custom JavaScript or Python validation function (returns row if valid, null if invalid).
Parameters
- language (Language, string, optional) — JavaScript or Python. Omitted language is JavaScript. Switching does not translate source. Allowed values:
javascript,python. - function (string, required) — JavaScript or Python function code. Default:
"".
Field selection
- source — Field whose values this operation reads. Use a single field name, a comma-separated list of plain field paths (
cash_flow_type, currency) from the multi-select UI, or a regex via Pattern mode. Omit to apply to all fields on the row. - target — Optional output field. When omitted, the source field is updated in place. Hidden when more than one named source field is selected.
JSON Configuration
{ "id": "op-function", "type": "validation", "action": "function", "params": { "language": "javascript", "function": "(cellValue, { row }) =>\n row.status === \"active\" ? row : null" }, "testInputs": [ "hello world", "valid row", "good value", "HELLO WORLD", "bad row", "invalid value" ]}Write Python with params.language set to python. Use def validate(cell_value, ctx):. Return True or the same ctx["row"] object to pass; return {"columnId": …, "message": …} to fail with that message. Stdlib plus from fontana import Currency. Import pandas when the function uses it.