FEAT-#7139: Use ray-core instead of ray-default

[anmyachev]

What do these changes do?

These changes are aimed at reducing the number of dependencies and thereby simplifying the installation of Modin with the Ray engine in the user environment. For example, we might not install dependencies for the Ray dashboard. To do this, we could use either package ray[client], but it appears only from version Ray>=2.6.0 (there is no desire to increase the minimally supported version of Ray so much for now), or switch to using the basic package itself (ray), but this will not work for fairly new versions of Ray, so how they don't include grpcio dependency.

As a transitional option, we can use the basic package with an explicit indication of grpcio package . This option will work, in this pull request, I tried it with different versions of Ray. However, there is a chance that grpcio package of some version will be installed, with which Ray has problems. Ray can explicitly exclude any versions in such cases (note: the exceptions are not made for the basic package, but for ray[client] package, so they cannot be reused on our side), but using the proposed approach, we most likely will not know about this until the problem arises for users.

If we decide to switch to such a transitional option, then I believe we should also consider switching to ray[client] package for Modin 1.0 release.

For example, dependencies for ray[default]==2.9.3:

        "default": [
            # If adding dependencies necessary to launch the dashboard api server,
            # please add it to dashboard/optional_deps.py as well.
            "aiohttp >= 3.7",
            "aiohttp_cors",
            "colorful",
            "py-spy >= 0.2.0",
            "requests",
            "gpustat >= 1.0.0",  # for windows
            "grpcio >= 1.32.0; python_version < '3.10'",  # noqa:E501
            "grpcio >= 1.42.0; python_version >= '3.10'",  # noqa:E501
            "opencensus",
            "pydantic!=2.0.*,!=2.1.*,!=2.2.*,!=2.3.*,!=2.4.*,<3",
            "prometheus_client >= 0.7.1",
            "smart_open",
            "virtualenv >=20.0.24, !=20.21.1",  # For pip runtime env.
        ],

• first commit message and PR title follow format outlined here

  NOTE: If you edit the PR title to match this format, you need to add another commit (even if it's empty) or amend your last commit for the CI job that checks the PR title to pick up the new PR title.

• passes flake8 modin/ asv_bench/benchmarks scripts/doc_checker.py
• passes black --check modin/ asv_bench/benchmarks scripts/doc_checker.py
• signed commit with git commit -s
• Resolves Simplify Modin on Ray installation #7139
• tests added and passing
• module layout described at docs/development/architecture.rst is up-to-date

[rkooo567]

I think there's no package that only includes cluster launcher. ray[client] is not for the cluster launcher (it is for ray client mode https://docs.ray.io/en/master/cluster/running-applications/job-submission/ray-client.html, which is not recommended to use)

[anmyachev]

I think there's no package that only includes cluster launcher. ray[client] is not for the cluster launcher (it is for ray client mode https://docs.ray.io/en/master/cluster/running-applications/job-submission/ray-client.html, which is not recommended to use)

@rkooo567 thanks! Now it’s more clear how to deal with this.

The base branch was changed.

[anmyachev]

It looks like we can safely remove ClientObjectRef from Modin sources. It was introduced in #2851. Ray fixed the problem a long time ago and defined the type like this: class ClientObjectRef(raylet.ObjectRef):

[YarShev]

Suggested change

	If you need those, consider installing `ray[default]` (through pip) along with `modin[ray]` or `ray-default` (through conda).
	If you need those, consider installing `ray[default]` (through pip) or `ray-default` (through conda) along with `modin[ray]`.

The first suggestion above.
The second is maybe we should also add this note to installation with conda below like.

**Note:** Since Modin 0.30.0 we use a reduced set of Ray dependencies: `ray-core` instead of `ray-default`.
This means that the dashboard and cluster launcher are no longer installed by default.
If you need those, consider installing `ray-default` along with `modin-ray`.

[YarShev]

I would go with the second one.

[anmyachev]

added