Method from_dict

celery/canvas.py:1511–1564

Create a group signature from a dictionary that represents a group. Example: >>> group_dict = { "task": "celery.group", "args": [], "kwargs": { "tasks": [ { "t

(cls, d, app=None)

    @classmethod
    def from_dict(cls, d, app=None):
        """Create a group signature from a dictionary that represents a group.

        Example:
            >>> group_dict = {
                "task": "celery.group",
                "args": [],
                "kwargs": {
                    "tasks": [
                        {
                            "task": "add",
                            "args": [
                                1,
                                2
                            ],
                            "kwargs": {},
                            "options": {},
                            "subtask_type": None,
                            "immutable": False
                        },
                        {
                            "task": "add",
                            "args": [
                                3,
                                4
                            ],
                            "kwargs": {},
                            "options": {},
                            "subtask_type": None,
                            "immutable": False
                        }
                    ]
                },
                "options": {},
                "subtask_type": "group",
                "immutable": False
            }
            >>> group_sig = group.from_dict(group_dict)

        Iterates over the given tasks in the dictionary and convert them to signatures.
        Tasks needs to be defined in d['kwargs']['tasks'] as a sequence
        of tasks.

        The tasks themselves can be dictionaries or signatures (or both).
        """
        # We need to mutate the `kwargs` element in place to avoid confusing
        # `freeze()` implementations which end up here and expect to be able to
        # access elements from that dictionary later and refer to objects
        # canonicalized here
        orig_tasks = d["kwargs"]["tasks"]
        d["kwargs"]["tasks"] = rebuilt_tasks = type(orig_tasks)(
            maybe_signature(task, app=app) for task in orig_tasks
        )
        return cls(rebuilt_tasks, app=app, **d['options'])

    def __init__(self, *tasks, **options):
        if len(tasks) == 1: