Return a `List` of metrics from client to server

[chongshenng]

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@Osama_Abu_Hamdan: Hello,
I am trying to return a List[int|float] of collected metrics from a client to the server when get_properties is called.
I get this error

TypeError: There is not a 1:1 mapping between `common.Scalar` types and those supported in `common.ConfigRecordValues` or `common.ConfigRecordValues`. Consider casting your values to a type supported by the `common.RecordDict` infrastructure. You used type: <class 'list'>

I checked the code and it only accepts scalars to be in return values. Any other way to pass metrics from client to server?
Best

@Chong_Shen: @Javier Can you please help with this question?

@Javier: Hi @Osama_Abu_Hamdan, returing a list is not supported. Only those types of type Scalar are supported. If you want to communicate a list I’d recommend you serialize it as a JSON for instance. Like this:

import json

def get_properties(self, config):
    # Original list of integers
    original_list = [1, 2, 3, 4, 5]

    # Serialize to string
    json_string = json.dumps(original_list)

    return {'my_property': json_string}

Then, on the receiving end (likely in your strategy) you just need to deserialize it:

# Deserialize back to list
restored_list = json.loads(json_string)

I hope this helps!!!

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