handle rate limits

utils.py

@@ -34,3 +34,35 @@ def removeprefix(s, prefix):
 	except AttributeError:
 		# compatibility for pre-3.9
 		return s[len(prefix):] if s.startswith(prefix) else s
+
+async def sleep_until(dt):
+	await anyio.sleep((dt - datetime.now(timezone.utc)).total_seconds())
+
+class HandleRateLimits:
+	def __init__(self, http):
+		self.http = http
+
+	def request(self, *args, **kwargs):
+		return _RateLimitContextManager(self.http, args, kwargs)
+
+class _RateLimitContextManager(contextlib.AbstractAsyncContextManager):
+	def __init__(self, http, args, kwargs):
+		self.http = http
+		self.args = args
+		self.kwargs = kwargs
+
+	async def __aenter__(self):
+		self._request_cm = self.http.request(*self.args, **self.kwargs)
+		return await self._do_enter()
+
+	async def _do_enter(self):
+		resp = await self._request_cm.__aenter__()
+		if resp.headers.get('X-RateLimit-Remaining') not in {'0', '1'}:
+			return resp
+
+		await sleep_until(datetime.fromisoformat(resp.headers['X-RateLimit-Reset']))
+		await self._request_cm.__aexit__(*(None,)*3)
+		return await self.__aenter__()
+
+	async def __aexit__(self, *excinfo):
+		return await self._request_cm.__aexit__(*excinfo)