Simplify and improve rest lifetime (#1230)

Signed-off-by: davfsa <davfsa@gmail.com>

changes/1230.breaking.md

@@ -0,0 +1 @@
+`RESTApp` and `RESTBucketManager` now need to be started and stopped by using `.start` and `.close`.

changes/1230.bugfix.md

@@ -0,0 +1 @@
+Buckets across different authentications are not shared any more, which would lead to incorrect rate limiting.

changes/1230.feature.md

@@ -0,0 +1,5 @@
+`RESTClientImpl` improvements:
+ - You can now share client sessions and bucket managers across these objects or have them created for you.
+ - Speedup of request lifetime
+ - No-ratelimit routes no longer attempt to acquire rate limits
+   - Just for safety, a check is in place to treat the route as a rate limited route if a bucket is ever received for it and a error log is emitted. If you spot it around, please inform us!

examples/oauth.py

@@ -0,0 +1,78 @@
+# -*- coding: utf-8 -*-
+# Hikari Examples - A collection of examples for Hikari.
+#
+# To the extent possible under law, the author(s) have dedicated all copyright
+# and related and neighboring rights to this software to the public domain worldwide.
+# This software is distributed without any warranty.
+#
+# You should have received a copy of the CC0 Public Domain Dedication along with this software.
+# If not, see <https://creativecommons.org/publicdomain/zero/1.0/>.
+"""An example OAuth server."""
+import logging
+import os
+
+from aiohttp import web
+
+import hikari
+
+logging.basicConfig(level=logging.DEBUG)
+
+host = "localhost"
+port = 8080
+CLIENT_ID = int(os.environ["CLIENT_ID"])  # ID as an int
+CLIENT_SECRET = os.environ["CLIENT_SECRET"]  # Secret as a str
+BOT_TOKEN = os.environ["BOT_TOKEN"]  # Token as a str
+CHANNEL_ID = int(os.environ["CHANNEL_ID"])  # Channel to post in as an int
+REDIRECT_URI = "http://localhost:8080"
+
+route_table = web.RouteTableDef()
+
+
+@route_table.get("/")
+async def oauth(request: web.Request) -> web.Response:
+    """Handle an OAuth request."""
+    code = request.query.get("code")
+    if not code:
+        return web.json_response({"error": "'code' is not provided"}, status=400)
+
+    discord_rest: hikari.RESTApp = request.app["discord_rest"]
+
+    # Exchange code to acquire a Bearer one for the user
+    async with discord_rest.acquire(None) as r:
+        auth = await r.authorize_access_token(CLIENT_ID, CLIENT_SECRET, code, REDIRECT_URI)
+
+    # Perform a request as the user to get their own user object
+    async with discord_rest.acquire(auth.access_token, hikari.TokenType.BEARER) as client:
+        user = await client.fetch_my_user()
+        # user is a hikari.OwnUser object where we can access attributes on it
+
+    # Notify the success
+    async with discord_rest.acquire(BOT_TOKEN, hikari.TokenType.BOT) as client:
+        await client.create_message(CHANNEL_ID, f"{user} ({user.id}) just authorized!")
+
+    return web.Response(text="Successfully authenticated!")
+
+
+async def start_discord_rest(app: web.Application) -> None:
+    """Start the RESTApp."""
+    discord_rest = hikari.RESTApp()
+    await discord_rest.start()
+
+    app["discord_rest"] = discord_rest
+
+
+async def stop_discord_rest(app: web.Application) -> None:
+    """Stop the RESTApp."""
+    discord_rest: hikari.RESTApp = app["discord_rest"]
+
+    await discord_rest.close()
+
+
+if __name__ == "__main__":
+    server = web.Application()
+    server.add_routes(route_table)
+
+    server.on_startup.append(start_discord_rest)
+    server.on_cleanup.append(stop_discord_rest)
+
+    web.run_app(server, host=host, port=port)

hikari/impl/bot.py

@@ -97,6 +97,21 @@ def _validate_activity(activity: undefined.UndefinedNoneOr[presences.Activity])
         )
 
 
+async def _close_resource(name: str, awaitable: typing.Awaitable[typing.Any]) -> None:
+    future = asyncio.ensure_future(awaitable)
+
+    try:
+        await future
+    except Exception as ex:
+        asyncio.get_running_loop().call_exception_handler(
+            {
+                "message": f"{name} raised an exception during shut down",
+                "future": future,
+                "exception": ex,
+            }
+        )
+
+
 class GatewayBot(traits.GatewayBotAware):
     """Basic auto-sharding bot implementation.
 
@@ -288,7 +303,7 @@ def __init__(
         intents: intents_.Intents = intents_.Intents.ALL_UNPRIVILEGED,
         auto_chunk_members: bool = True,
         logs: typing.Union[None, int, str, typing.Dict[str, typing.Any]] = "INFO",
-        max_rate_limit: float = 300,
+        max_rate_limit: float = 300.0,
         max_retries: int = 3,
         proxy_settings: typing.Optional[config_impl.ProxySettings] = None,
         rest_url: typing.Optional[str] = None,
@@ -426,30 +441,14 @@ async def close(self) -> None:
         await self._event_manager.dispatch(self._event_factory.deserialize_stopping_event())
         _LOGGER.log(ux.TRACE, "StoppingEvent dispatch completed, now beginning termination")
 
-        loop = asyncio.get_running_loop()
-
-        async def handle(name: str, awaitable: typing.Awaitable[typing.Any]) -> None:
-            future = asyncio.ensure_future(awaitable)
-
-            try:
-                await future
-            except Exception as ex:
-                loop.call_exception_handler(
-                    {
-                        "message": f"{name} raised an exception during shut down",
-                        "future": future,
-                        "exception": ex,
-                    }
-                )
-
-        await handle("voice handler", self._voice.close())
+        await _close_resource("voice handler", self._voice.close())
 
-        shards = tuple((handle(f"shard {s.id}", s.close()) for s in self._shards.values() if s.is_alive))
+        shards = tuple(_close_resource(f"shard {s.id}", s.close()) for s in self._shards.values() if s.is_alive)
 
         for coro in asyncio.as_completed(shards):
             await coro
 
-        await handle("rest", self._rest.close())
+        await _close_resource("rest", self._rest.close())
 
         # Clear out cache and shard map
         self._cache.clear()