xworkflows 0.4.0

Links

• Package on PyPI: http://pypi.python.org/pypi/xworkflows

• Repository and issues on GitHub: http://github.com/rbarrois/xworkflows

• Doc on http://readthedocs.org/docs/xworkflows/

Example

It allows to easilly define a workflow, attach it to a class, and use its transitions:

class MyWorkflow(xworkflows.Workflow):
    # A list of state names
    states = (
        ('foo', _(u"Foo")),
        ('bar', _(u"Bar")),
        ('baz', _(u"Baz")),
    )
    # A list of transition definitions; items are (name, source states, target).
    transitions = (
        ('foobar', 'foo', 'bar'),
        ('gobaz', ('foo', 'bar'), 'baz'),
        ('bazbar', 'baz', 'bar'),
    )
    initial_state = 'foo'


class MyObject(xworkflows.WorkflowEnabled):
    state = MyWorkflow()

    @transition()
    def foobar(self):
        return 42

    # It is possible to use another method for a given transition.
    @transition('gobaz')
    def blah(self):
        return 13

>>> o = MyObject()
>>> o.state
State('foo')
>>> o.state.is_foo
True

>>> o.foobar()
42
>>> o.state
State('bar')

>>> o.blah()
13
>>> o.state
State('baz')

Hooks

Custom functions can be hooked to transactions, in order to run before/after a transition, when entering a state, when leaving a state, …:

class MyObject(xworkflows.WorkflowEnabled):

    state = MyWorkflow()

    @xworkflows.before_transition('foobar')
    def my_hook(self, *args, **kwargs):
        # *args and **kwargs are those passed to MyObject.foobar(...)
        pass

    @xworkflows.on_enter_state('bar')
    def my_other_hook(self, result, *args, **kwargs):
        # Will be called just after any transition entering 'bar'
        # result is the value returned by that transition
        # *args, **kwargs are the arguments/keyword arguments passed to the
        # transition.
        pass