Function compute_layer_dependencies

dask/highlevelgraph.py:34–48

Returns the dependencies between layers

(layers)

def compute_layer_dependencies(layers):
    """Returns the dependencies between layers"""

    def _find_layer_containing_key(key):
        for k, v in layers.items():
            if key in v:
                return k
        raise RuntimeError(f"{key!r} not found")

    all_keys = {key for layer in layers.values() for key in layer}
    ret = {k: set() for k in layers}
    for k, v in layers.items():
        for key in keys_in_tasks(all_keys - v.keys(), v.values()):
            ret[k].add(_find_layer_containing_key(key))
    return ret


class Layer(Graph):