chore: import upstream snapshot with attribution

agentlightning/execution/base.py

@@ -0,0 +1,64 @@
+# Copyright (c) Microsoft. All rights reserved.
+
+from __future__ import annotations
+
+import logging
+from typing import Protocol
+
+from agentlightning.store.base import LightningStore
+
+from .events import ExecutionEvent
+
+logger = logging.getLogger(__name__)
+
+
+class AlgorithmBundle(Protocol):
+    """Callable bundle produced by [`Trainer`][agentlightning.Trainer].
+
+    Execution strategies treat the returned coroutine as opaque, only providing
+    the shared store instance and cooperative stop event. Bundles typically
+    encapsulate algorithm setup plus adapter and LLM proxy, etc.
+    """
+
+    async def __call__(self, store: LightningStore, event: ExecutionEvent) -> None:
+        """Execute algorithm logic using ``store`` until completion or stop."""
+
+
+class RunnerBundle(Protocol):
+    """Callable bundle wrapping runner setup and the worker loop, as opposed to the
+    [`AlgorithmBundle`][agentlightning.AlgorithmBundle]."""
+
+    async def __call__(self, store: LightningStore, worker_id: int, event: ExecutionEvent) -> None:
+        """Execute runner logic for ``worker_id`` using ``store`` and ``event``."""
+
+
+class ExecutionStrategy:
+    """Coordinate algorithm and runner bundles within a single process abstraction.
+
+    Strategies decide how many worker bundles to launch, whether to communicate
+    through shared memory or an HTTP boundary, and how to react to shutdown
+    signals. They intentionally avoid inspecting the bundle internals; instead,
+    each bundle remains responsible for its own scheduling semantics.
+
+    !!! note
+        Implementations must honor the [execute()][agentlightning.ExecutionStrategy.execute]
+        contract by propagating `KeyboardInterrupt` and ensuring resources are
+        released when an error occurs on either side of the algorithm/runner
+        pair.
+    """
+
+    def execute(self, algorithm: AlgorithmBundle, runner: RunnerBundle, store: LightningStore) -> None:
+        """Run the provided bundles using the configured orchestration model.
+
+        Args:
+            algorithm: Callable bundle responsible for algorithm execution.
+            runner: Callable bundle for runner workers.
+            store: Concrete [`LightningStore`][agentlightning.LightningStore]
+                shared across bundles.
+
+        Raises:
+            NotImplementedError: Subclasses must provide the orchestration
+                implementation.
+        """
+
+        raise NotImplementedError()