Module table.pick.column in plugin tabular v0.5.2

Pick one column from a table, returning an array.

Author(s)	Markus Binsteiner (markus@frkl.io)
Tags	tabular
Python class	kiara_plugin.tabular.modules.table.PickColumnModule

Configuration

Module configuration options

Configuration class: kiara_plugin.tabular.modules.table.PickColumnModuleConfig

Name	Description	Type	Required?	Default
column_name	A hardcoded column name to cut.	anyOf: [{'type': 'string'}, {'type': 'null'}]	false	null
constants	Value constants for this module.	object	false	null
defaults	Value defaults for this module.	object	false	null

Source code

Module source code

class PickColumnModule(KiaraModule):
    """Pick one column from a table, returning an array."""

    _module_type_name = "table.pick.column"
    _config_cls = PickColumnModuleConfig

    def create_inputs_schema(
        self,
    ) -> ValueMapSchema:

        inputs: Dict[str, Any] = {"table": {"type": "table", "doc": "A table."}}
        column_name = self.get_config_value("column_name")
        if not column_name:
            inputs["column_name"] = {
                "type": "string",
                "doc": "The name of the column to extract.",
            }

        return inputs

    def create_outputs_schema(
        self,
    ) -> ValueMapSchema:

        outputs: Mapping[str, Any] = {"array": {"type": "array", "doc": "The column."}}
        return outputs

    def process(self, inputs: ValueMap, outputs: ValueMap) -> None:

        import pyarrow as pa

        column_name: Union[str, None] = self.get_config_value("column_name")
        if not column_name:
            column_name = inputs.get_value_data("column_name")

        if not column_name:
            raise KiaraProcessingException(
                "Could not cut column from table: column_name not provided or empty string."
            )

        table_value: Value = inputs.get_value_obj("table")
        table_metadata: KiaraTableMetadata = table_value.get_property_data(
            "metadata.table"
        )
        available = table_metadata.table.column_names

        if column_name not in available:
            raise KiaraProcessingException(
                f"Invalid column name '{column_name}'. Available column names: {', '.join(available)}"
            )

        table: pa.Table = table_value.data.arrow_table
        column = table.column(column_name)

        outputs.set_value("array", column)