Unified Way of Serializing Spaces and Samples from Spaces

[maximilianreimer]

Currently gym.Spaces as well as the sample drawn from them are serialized to JSON in different ways producing duplicated code and incompatible formats at a different places of the program.

Known serialization code locations:

• dacbench.abstract_benchmark.AbstractBenchmark.load_config(...)
• dacbench.abstract_env.AbstractEnv.__init__(...)
• dacbench.container.container_utils.Encoder and dacbench.container.container_utils.Decoder

Related to #91 and #80

[maximilianreimer]

Serialization of Dict Spaces done by AbstractBenchmark does not work properly. See falling tests in https://github.com/automl/DACBench/tree/container_draft/tests/benchmarks

Should be replace by serialization from dacbench.container.container_utils.Encoderanddacbench.container.container_utils.Decoder` and code should be move somewhere else.

The way of storing spaces will change which requires conversion of existing serialized benchmark configs. We should provide a small script that takes care of this.

Summary:

• Change serialization of spaces in benchmark configs to the one in Encoder / Decoder, maybe extend the classes to handle the whole benchmark config?
• Add scrip for conversion of old config format to new
• Convert old benchmark configs.

[TheEimer]

We should implement #80 before we tackle this