composer_replication/recipes/monarch/actors.py

"""Monarch actor skeletons — DESIGN/SKELETON for v0.

Per ADR-006, full Monarch integration is deferred to v0.2+. This file
documents the actor signatures so the framework's recipe matrix is
complete.

Importing this module does NOT require monarch installed; the imports
are deferred inside class bodies. Real instantiation will fail without
monarch, which is the desired behavior for a recipe document.
"""
from __future__ import annotations

from typing import Any


class TrainerActor:
    """Hosts the framework's 3-channel composer trainer.

    Real implementation (v0.2+):

        from monarch import Actor, endpoint

        class TrainerActor(Actor):
            @endpoint
            async def train_outer_step(self, batch_id: int) -> dict:
                # 1. Pull batch from generator
                # 2. Run inner H steps with composer compose_loss
                # 3. Compute pseudo-gradient
                # 4. Hand to ObjectStoreAllReduce manager
                # 5. Apply outer SGD step
                # 6. Return metrics dict
                ...

    For v0 the actor is just a documentation stub.
    """
    backend = "monarch"
    role = "trainer"

    def __init__(self) -> None:
        raise NotImplementedError(
            "Monarch trainer actor is a v0 skeleton; implementation "
            "deferred to v0.2 per ADR-006."
        )

    async def train_outer_step(self, batch_id: int) -> dict[str, Any]:
        raise NotImplementedError


class GeneratorActor:
    """vllm-backed rollout actor."""
    backend = "monarch"
    role = "generator"

    def __init__(self) -> None:
        raise NotImplementedError("v0 skeleton — see ADR-006.")

    async def rollout(self, prompts: list[str]) -> list[str]:
        raise NotImplementedError


class RewarderActor:
    """verifiers-protocol rewarder for RLVR-style RL."""
    backend = "monarch"
    role = "rewarder"

    def __init__(self) -> None:
        raise NotImplementedError("v0 skeleton — see ADR-006.")

    async def score(self, completions: list[str]) -> list[float]:
        raise NotImplementedError


class TeacherPoolActor:
    """Channel-3 teacher pool — wraps composer_replication.teacher_replay."""
    backend = "monarch"
    role = "teacher_pool"

    def __init__(self) -> None:
        raise NotImplementedError("v0 skeleton — see ADR-006.")

    async def replay(self, states: list[dict]) -> list[dict]:
        raise NotImplementedError


__all__ = [
    "GeneratorActor",
    "RewarderActor",
    "TeacherPoolActor",
    "TrainerActor",
]