Outputter

A type of Callable that outputs a pipeline result.

Definition

Constructor

class controller.callable.extractor.Extractor(self, id: str, params: CallableParameters)

An abstract subclass of Callable where its implementations are Callables that outputs a pipeline result.

Parameters:

• id (str) – The unique identifier of this Callable. Also referred to as callable_id in documentations for specific Callables.

• params (CallableParameters) – The parameters of this Callable. Refer to the documentation for a specific Callable for details.

Methods

abstract controller.callable.Callable.check_params(self, params: CallableParameters) → boolean

See Callable.

abstract controller.callable.Callable.exec(self, data: pd.DataFrame, **kwargs) → pd.DataFrame

See Callable.

Usage

A concrete implementation of a Callable may inherit this class and override its check_params() and exec() methods.

Output conventions

Refer to Callable for conventions on all Callable outputs.

• Outputter output conventions require the output DataFrame to contain 2 columns only.

  <callable_id>.output	<callable_id>.type
  buffer	mime type

  • The first column is named <callable_id>.output. It contains a BytesIO object – a bytes buffer for streaming binary data – storing bytes of the data to be outputted as the pipeline result.

  • The second column is named <callable_id>.type. It contains a str that specifies the MIME type of the output buffer. Refer to https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types for a list of common MIME types.

• An output DataFrame from an Outputter is not designed to be passed into subsequent Callables for further processing.