luigi.task_register module

Define the centralized register of all Task classes.

exception luigi.task_register.TaskClassException[source]

Bases: Exception

exception luigi.task_register.TaskClassNotFoundException[source]

Bases: TaskClassException

exception luigi.task_register.TaskClassAmbigiousException[source]

Bases: TaskClassException

class luigi.task_register.Register(classname, bases, classdict, **kwargs)[source]

Bases: ABCMeta

The Metaclass of Task.

Acts as a global registry of Tasks with the following properties:

  1. Cache instances of objects so that eg. X(1, 2, 3) always returns the same object.

  2. Keep track of all subclasses of Task and expose them.

Custom class creation for namespacing.

Also register all subclasses.

When the set or inherited namespace evaluates to None, set the task namespace to whatever the currently declared namespace is.

AMBIGUOUS_CLASS = <object object>

If this value is returned by _get_reg() then there is an ambiguous task name (two Task have the same name). This denotes an error.

classmethod clear_instance_cache()[source]

Clear/Reset the instance cache.

classmethod disable_instance_cache()[source]

Disables the instance cache.

property task_family

Internal note: This function will be deleted soon.

classmethod task_names()[source]

List of task names as strings

classmethod tasks_str()[source]

Human-readable register contents dump.

classmethod get_task_cls(name)[source]

Returns an unambiguous class or raises an exception.

classmethod get_all_params()[source]

Compiles and returns all parameters for all Task.


a generator of tuples (TODO: we should make this more elegant)

luigi.task_register.load_task(module, task_name, params_str)[source]

Imports task dynamically given a module and a task name.