Ray: Can't create remote actor without decorator and apply arguments

[zplizzi]

System information

• OS Platform and Distribution (e.g., Linux Ubuntu 16.04): Ubuntu 16.04
• Ray installed from (source or binary): binary
• Ray version: 0.7.6
• Python version: 3.6.8

import ray

ray.init()

class Test:
    def __init__(self):
        pass

actor = ray.remote(Test, num_cpus=1).remote()

fails with

AssertionError: The @ray.remote decorator must be applied either with no arguments and no parentheses, for example '@ray.remote', or it must be applied using some of the arguments 'num_return_vals', 'num_cpus', 'num_gpus', 'memory', 'object_store_memory', 'resources', 'max_calls', or 'max_reconstructions', like '@ray.remote(num_return_vals=2, resources={"CustomResource": 1})'.

Doing the same thing with a decorator (@ray.remote(num_cpus=1)) works, but I want to be able to use classes with and without Ray (eg for unit tests), so I don't want to use decorators.

[richardliaw]

Try:

actor = ray.remote(num_cpus=1)(Test).remote()

# is equivalent to:

RemoteTestClass = ray.remote(num_cpus=1)(Test)
actor = RemoteTestClass.remote()

[zplizzi]

Gotcha, that works. The example in the docs is
Counter = ray.remote(Counter)
which is how I got to my approach. Perhaps another example could be provided with your method?

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