Source code for openalea.oalab.service.applet

from openalea.core.plugin import iter_plugins


class Applet(object):
    # TODO: become a manager ??
    _applets = {}

    @classmethod
    def register(cls, applet_name, applet):
        cls._applets[applet_name] = applet

    @classmethod
    def new(cls, name, klass, *args, **kwargs):
        if name in cls._applets:
            return cls._applets[name]
        else:
            applet = klass(*args, **kwargs)
            cls.register(name, applet)
            return applet

    @classmethod
    def instances(cls, **kwargs):
        return cls._applets.values()

    @classmethod
    def instance(cls, **kwargs):
        """
        This is a temporary service that will be replaced by more specialized service or
        services based on interface
        """
        if 'class_args' in kwargs:
            class_args = kwargs['class_args']
        else:
            class_args = {}

        instance = None
        err = 'Cannot find required applet'

        if 'identifier' in kwargs:
            identifier = kwargs['identifier']
            err = 'No applet named %s' % identifier
            if identifier in cls._applets:
                instance = cls._applets[identifier]
                return instance
            else:
                for plugin in iter_plugins('oalab.applet'):
                    if plugin.name == identifier:
                        instance = plugin()
                        applet = instance(**class_args)
                        cls.register_applet(plugin.name, applet)
                        instance = cls._applets[identifier]
                        return instance
        raise NotImplementedError, err


register_applet = Applet.register
new_applet = Applet.new

from openalea.core.service.plugin import plugin_instances, plugin_instance


def get_applets():
    return plugin_instances('oalab.applet')

def get_applet(**kwargs):
    if 'class_args' in kwargs:
        class_args = kwargs['class_args']
    else:
        class_args = {}

    instance = None
    err = 'Cannot find required applet'

    if 'identifier' in kwargs:
        identifier = kwargs['identifier']

        return plugin_instance('oalab.applet', identifier, class_kwds=class_args)