feat(ext-loader): Support async setup functions

Allow extension `setup` functions to be asynchronous. The loader now checks if `module.setup` returns an awaitable and runs it using asyncio, handling cases where an event loop is already running or not.

This enables extensions to perform asynchronous initialization tasks.

disagreement/ext/loader.py

@@ -1,9 +1,11 @@
 from __future__ import annotations
 
+import asyncio
 from importlib import import_module
+import inspect
 import sys
 from types import ModuleType
-from typing import Dict
+from typing import Any, Coroutine, Dict, cast
 
 __all__ = ["load_extension", "unload_extension", "reload_extension"]
 
@@ -25,7 +27,20 @@ def load_extension(name: str) -> ModuleType:
     if not hasattr(module, "setup"):
         raise ImportError(f"Extension '{name}' does not define a setup function")
 
-    module.setup()
+    result = module.setup()
+    if inspect.isawaitable(result):
+        coro = cast(Coroutine[Any, Any, Any], result)
+        try:
+            loop = asyncio.get_running_loop()
+        except RuntimeError:
+            asyncio.run(coro)
+        else:
+            if loop.is_running():
+                future = asyncio.run_coroutine_threadsafe(coro, loop)
+                future.result()
+            else:
+                loop.run_until_complete(coro)
+
     _loaded_extensions[name] = module
     return module
 

tests/test_extension_loader.py

@@ -22,6 +22,22 @@ def create_dummy_module(name):
     return called
 
 
+def create_async_module(name):
+    mod = types.ModuleType(name)
+    called = {"setup": False, "teardown": False}
+
+    async def setup():
+        called["setup"] = True
+
+    def teardown():
+        called["teardown"] = True
+
+    mod.setup = setup
+    mod.teardown = teardown
+    sys.modules[name] = mod
+    return called
+
+
 def test_load_and_unload_extension():
     called = create_dummy_module("dummy_ext")
 
@@ -75,3 +91,13 @@ def test_reload_extension(monkeypatch):
 
     loader.unload_extension("reload_ext")
     assert called_second["teardown"] is True
+
+
+def test_async_setup():
+    called = create_async_module("async_ext")
+
+    loader.load_extension("async_ext")
+    assert called["setup"] is True
+
+    loader.unload_extension("async_ext")
+    assert called["teardown"] is True