Call plugin unload function after stopping event loop (SteamDeckHomeb…

…rew#539)

This can prevent race conditions where unload is clearing data but main is still working with it

backend/src/plugin.py

@@ -0,0 +1,168 @@
+import multiprocessing
+from asyncio import (Lock, get_event_loop, new_event_loop,
+                     set_event_loop, sleep)
+from importlib.util import module_from_spec, spec_from_file_location
+from json import dumps, load, loads
+from logging import getLogger
+from traceback import format_exc
+from os import path, environ
+from signal import SIGINT, signal
+from sys import exit, path as syspath, modules as sysmodules
+from typing import Any, Dict
+from .localsocket import LocalSocket
+from .localplatform import setgid, setuid, get_username, get_home_path
+from .customtypes import UserType
+from . import helpers
+
+class PluginWrapper:
+    def __init__(self, file: str, plugin_directory: str, plugin_path: str) -> None:
+        self.file = file
+        self.plugin_path = plugin_path
+        self.plugin_directory = plugin_directory
+        self.method_call_lock = Lock()
+        self.socket: LocalSocket = LocalSocket(self._on_new_message)
+
+        self.version = None
+
+        json = load(open(path.join(plugin_path, plugin_directory, "plugin.json"), "r", encoding="utf-8"))
+        if path.isfile(path.join(plugin_path, plugin_directory, "package.json")):
+            package_json = load(open(path.join(plugin_path, plugin_directory, "package.json"), "r", encoding="utf-8"))
+            self.version = package_json["version"]
+
+        self.legacy = False
+        self.main_view_html = json["main_view_html"] if "main_view_html" in json else ""
+        self.tile_view_html = json["tile_view_html"] if "tile_view_html" in json else ""
+        self.legacy = self.main_view_html or self.tile_view_html
+
+        self.name = json["name"]
+        self.author = json["author"]
+        self.flags = json["flags"]
+
+        self.log = getLogger("plugin")
+
+        self.passive = not path.isfile(self.file)
+
+    def __str__(self) -> str:
+        return self.name
+
+    def _init(self):
+        try:
+            signal(SIGINT, lambda s, f: exit(0))
+
+            set_event_loop(new_event_loop())
+            if self.passive:
+                return
+            setgid(UserType.ROOT if "root" in self.flags else UserType.HOST_USER)
+            setuid(UserType.ROOT if "root" in self.flags else UserType.HOST_USER)
+            # export a bunch of environment variables to help plugin developers
+            environ["HOME"] = get_home_path(UserType.ROOT if "root" in self.flags else UserType.HOST_USER)
+            environ["USER"] = "root" if "root" in self.flags else get_username()
+            environ["DECKY_VERSION"] = helpers.get_loader_version()
+            environ["DECKY_USER"] = get_username()
+            environ["DECKY_USER_HOME"] = helpers.get_home_path()
+            environ["DECKY_HOME"] = helpers.get_homebrew_path()
+            environ["DECKY_PLUGIN_SETTINGS_DIR"] = path.join(environ["DECKY_HOME"], "settings", self.plugin_directory)
+            helpers.mkdir_as_user(path.join(environ["DECKY_HOME"], "settings"))
+            helpers.mkdir_as_user(environ["DECKY_PLUGIN_SETTINGS_DIR"])
+            environ["DECKY_PLUGIN_RUNTIME_DIR"] = path.join(environ["DECKY_HOME"], "data", self.plugin_directory)
+            helpers.mkdir_as_user(path.join(environ["DECKY_HOME"], "data"))
+            helpers.mkdir_as_user(environ["DECKY_PLUGIN_RUNTIME_DIR"])
+            environ["DECKY_PLUGIN_LOG_DIR"] = path.join(environ["DECKY_HOME"], "logs", self.plugin_directory)
+            helpers.mkdir_as_user(path.join(environ["DECKY_HOME"], "logs"))
+            helpers.mkdir_as_user(environ["DECKY_PLUGIN_LOG_DIR"])
+            environ["DECKY_PLUGIN_DIR"] = path.join(self.plugin_path, self.plugin_directory)
+            environ["DECKY_PLUGIN_NAME"] = self.name
+            if self.version:
+                environ["DECKY_PLUGIN_VERSION"] = self.version
+            environ["DECKY_PLUGIN_AUTHOR"] = self.author
+
+            # append the plugin's `py_modules` to the recognized python paths
+            syspath.append(path.join(environ["DECKY_PLUGIN_DIR"], "py_modules"))
+
+            #TODO: FIX IN A LESS CURSED WAY
+            keys = [key.replace("src.", "") for key in sysmodules if key.startswith("src.")]
+            for key in keys:
+                sysmodules[key] = sysmodules["src"].__dict__[key]
+
+            spec = spec_from_file_location("_", self.file)
+            assert spec is not None
+            module = module_from_spec(spec)
+            assert spec.loader is not None
+            spec.loader.exec_module(module)
+            self.Plugin = module.Plugin
+
+            if hasattr(self.Plugin, "_migration"):
+                get_event_loop().run_until_complete(self.Plugin._migration(self.Plugin))
+            if hasattr(self.Plugin, "_main"):
+                get_event_loop().create_task(self.Plugin._main(self.Plugin))
+            get_event_loop().create_task(self.socket.setup_server())
+            get_event_loop().run_forever()
+        except:
+            self.log.error("Failed to start " + self.name + "!\n" + format_exc())
+            exit(0)
+
+    async def _unload(self):
+        try:
+            self.log.info("Attempting to unload with plugin " + self.name + "'s \"_unload\" function.\n")
+            if hasattr(self.Plugin, "_unload"):
+                await self.Plugin._unload(self.Plugin)
+                self.log.info("Unloaded " + self.name + "\n")
+            else:
+                self.log.info("Could not find \"_unload\" in " + self.name + "'s main.py" + "\n")
+        except:
+            self.log.error("Failed to unload " + self.name + "!\n" + format_exc())
+            exit(0)
+
+    async def _on_new_message(self, message : str) -> str|None:
+        data = loads(message)
+
+        if "stop" in data:
+            self.log.info("Calling Loader unload function.")
+            get_event_loop().stop()
+            while get_event_loop().is_running():
+                await sleep(0)
+            get_event_loop().close()
+            await self._unload()
+            raise Exception("Closing message listener")
+
+        # TODO there is definitely a better way to type this
+        d: Dict[str, Any] = {"res": None, "success": True}
+        try:
+            d["res"] = await getattr(self.Plugin, data["method"])(self.Plugin, **data["args"])
+        except Exception as e:
+            d["res"] = str(e)
+            d["success"] = False
+        finally:
+            return dumps(d, ensure_ascii=False)
+
+    def start(self):
+        if self.passive:
+            return self
+        multiprocessing.Process(target=self._init).start()
+        return self
+
+    def stop(self):
+        if self.passive:
+            return
+
+        async def _(self: PluginWrapper):
+            await self.socket.write_single_line(dumps({ "stop": True }, ensure_ascii=False))
+            await self.socket.close_socket_connection()
+
+        get_event_loop().create_task(_(self))
+
+    async def execute_method(self, method_name: str, kwargs: Dict[Any, Any]):
+        if self.passive:
+            raise RuntimeError("This plugin is passive (aka does not implement main.py)")
+        async with self.method_call_lock:
+            # reader, writer = 
+            await self.socket.get_socket_connection()
+
+            await self.socket.write_single_line(dumps({ "method": method_name, "args": kwargs }, ensure_ascii=False))
+
+            line = await self.socket.read_single_line()
+            if line != None:
+                res = loads(line)
+                if not res["success"]:
+                    raise Exception(res["res"])
+                return res["res"]