[WIP] Observation Types

[awjuliani]

Proposed change(s)

Adds a ObservationType field to the ObservationSpec.

ObservationType is an enum consisting of one of the following:

• Default
• Goal
• Reward
• Message

Todo:

• Mark new C# interface as internal.
• Ensure all current observation sensors are marked as observations.
• Modify all tests.

Useful links (Github issues, JIRA tickets, ML-Agents forum threads etc.)

Types of change(s)

• Bug fix
• New feature
• Code refactor
• Breaking change
• Documentation update
• Other (please describe)

Checklist

• Added tests that prove my fix is effective or that my feature works
• Updated the changelog (if applicable)
• Updated the documentation (if applicable)
• Updated the migration guide (if applicable)

Other comments

[chriselion]

Did you expect this file to change (especially with this new class)?

[awjuliani]

This is an artifact of my building the proto files using a newer version of grpc-tools, as I am still unable to install older versions. I'll try again to figure out the problem and build these with the version we are using internally though, since there are obviously discrepancies in what is being produced.

[chriselion]

General feedback:

• Should this be called ObservationType instead of SensorType?
• Is there a less generic term that we can use than "(Sensor/Observation)Type"? That would also get around using type as a member variable on the python side, which is OK but discouraged since it's a builtin function.

[awjuliani]

General feedback:

• Should this be called ObservationType instead of SensorType?
• Is there a less generic term that we can use than "(Sensor/Observation)Type"? That would also get around using type as a member variable on the python side, which is OK but discouraged since it's a builtin function.

Thanks for the code review, Chris. These are both good questions. The issue with ObservationType is that one of those types is "Observation," so we'd need to change whatever that is called to disambiguate it. Vince actually renamed the ObservationSpec to a SensorSpec, so this naming for the "type" lines us.

I agree though that "type" is too generic, and potentially problematic wrt python naming. Definitely open to other more appropriate names for it.

[vincentpierre]

Shouldn't this interface be public? Are users expected to add ObservationType to their sensors or not for now?

[chriselion]

It doesn't need to be, since any ISensor that isn't an ITypedSensor should be treated as Default type.

[awjuliani]

Intention is similar to making the DimensionProperty internal for now. To not change the public API until there are actual features to use it.