mars.contrib.dask.converter 源代码
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# Licensed under the Apache License, Version 2.0 (the "License");
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#
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from dask import is_dask_collection, optimize
from dask.bag import Bag
from ...remote import spawn
from .scheduler import mars_dask_get
from .utils import reduce
[文档]def convert_dask_collection(dc):
"""
Convert dask collection object into mars.core.Object via remote API
Parameters
----------
dc: dask collection
Dask collection object to be converted.
Returns
-------
Object
Mars Object.
"""
if not is_dask_collection(dc):
raise TypeError(f"'{type(dc).__name__}' object is not a valid dask collection")
dc.__dask_graph__().validate()
dsk = optimize(dc)[0].__dask_graph__()
first_key = next(iter(dsk.keys()))
if isinstance(first_key, str):
key = [first_key]
elif isinstance(first_key, tuple):
key = sorted(
[i for i in dsk.keys() if i[0] == first_key[0]], key=lambda x: x[1]
)
else:
raise ValueError(
f"Dask collection object seems be broken, with unexpected key type:'{type(first_key).__name__}'"
)
res = reduce(mars_dask_get(dsk, [key]))
if isinstance(dc, Bag):
return spawn(lambda x: list(x[0][0]), args=(res,))
else:
return res