satif_core.transformers.base

Transformer Objects

class Transformer(ABC)

Abstract Base Class for data transformation.

This class defines the interface for all transformer implementations. Transformers are responsible for taking SDIF (Standardized Data Interchange Format) data as input, performing some transformation logic, and producing output data, which can then be exported to various file formats.

Concrete implementations of this class should provide logic for the transform and _export_data methods.

transform

@abstractmethod
def transform(
    sdif: Union[SDIFPath, List[SDIFPath], SDIFDatabase, Dict[str, SDIFPath]]
) -> Dict[str, Any]

Transforms input SDIF data into an in-memory representation.

This method should be implemented by subclasses to define the core transformation logic. It takes one or more SDIF sources, processes them, and returns a dictionary where keys are intended output filenames and values are the data to be written to these files (e.g., pandas DataFrames, dictionaries, lists, strings, or bytes).

Arguments:

• sdif - The SDIF data source(s) to transform. This can be:

  • A single SDIF file path (str or Path).

  • A list of SDIF file paths.

  • An SDIFDatabase instance.

  • A dictionary mapping custom schema names (str) to SDIF file paths.

Returns:

A dictionary where keys are relative output filenames (e.g., "data.csv") and values are the corresponding transformed data objects.

Raises:

• NotImplementedError - If the method is not implemented by a subclass.
• FileNotFoundError - If any input SDIF file path does not exist.
• ValueError - If input arguments are invalid or incompatible.
• Exception - Subclasses may raise specific exceptions related to transformation errors (e.g., database errors, data processing issues).

export

def export(sdif: Union[SDIFPath, List[SDIFPath], SDIFDatabase, Dict[str,
                                                                    SDIFPath]],
           output_path: Union[str, Path] = Path("."),
           zip_archive: bool = False) -> Path

Transforms SDIF data and exports the results to files.

This is a convenience method that orchestrates the transformation and export process. It first calls the transform method to get the in-memory transformed data, and then calls the _export_data method to write this data to the specified output path.

Arguments:

• sdif - The SDIF data source(s) to transform. Passed directly to the transform method. See transform method docstring for details.

• output_path - The base path for output. Passed directly to the _export_data method. See _export_data method docstring for details. Defaults to the current directory.

• zip_archive - If True, package all output files into a single ZIP archive. Passed directly to the _export_data method. Defaults to False.

Returns:

The absolute path to the created output file or directory. See _export_data method return value for more details.

Raises:

This method can raise any exceptions thrown by transform or _export_data methods (e.g., FileNotFoundError, ValueError, IOError).