Rate limit API requests

custom_components/candy/client/__init__.py

@@ -7,11 +7,18 @@
 import backoff
 from aiohttp import ClientSession
 
+from aiolimiter import AsyncLimiter
+
 from .decryption import decrypt, Encryption, find_key
 from .model import WashingMachineStatus, TumbleDryerStatus, DishwasherStatus, OvenStatus
 
 _LOGGER = logging.getLogger(__name__)
 
+# Some devices reportedly can't handle too frequent requests and respond with BAD_REQUEST
+# This global limiter makes sure we don't call the API too fast
+# https://github.com/ofalvai/home-assistant-candy/issues/61
+_LIMITER = AsyncLimiter(max_rate=1, time_period=3)
+
 
 class CandyClient:
 
@@ -28,7 +35,7 @@ async def status_with_retry(self) -> Union[WashingMachineStatus, TumbleDryerStat
 
     async def status(self) -> Union[WashingMachineStatus, TumbleDryerStatus, DishwasherStatus, OvenStatus]:
         url = _status_url(self.device_ip, self.use_encryption)
-        async with self.session.get(url) as resp:
+        async with _LIMITER, self.session.get(url) as resp:
             if self.use_encryption:
                 resp_hex = await resp.text()  # Response is hex encoded, either encrypted or not
                 if self.encryption_key != "":
@@ -61,7 +68,7 @@ async def detect_encryption(session: aiohttp.ClientSession, device_ip: str) -> (
     try:
         _LOGGER.info("Trying to get a response without encryption (encrypted=0)...")
         url = _status_url(device_ip, use_encryption=False)
-        async with session.get(url) as resp:
+        async with _LIMITER, session.get(url) as resp:
             resp_json = await resp.json(content_type="text/html")
             assert resp_json.get("response") != "BAD REQUEST"
             _LOGGER.info("Received unencrypted JSON response, no need to use key for decryption")
@@ -70,7 +77,7 @@ async def detect_encryption(session: aiohttp.ClientSession, device_ip: str) -> (
         _LOGGER.debug(e)
         _LOGGER.info("Failed to get a valid response without encryption, let's try with encrypted=1...")
         url = _status_url(device_ip, use_encryption=True)
-        async with session.get(url) as resp:
+        async with _LIMITER, session.get(url) as resp:
             resp_hex = await resp.text()  # Response is hex encoded encrypted data
             try:
                 json.loads(bytes.fromhex(resp_hex))

custom_components/candy/manifest.json

@@ -6,7 +6,8 @@
   "documentation": "https://github.com/ofalvai/home-assistant-candy",
   "issue_tracker": "https://github.com/ofalvai/home-assistant-candy/issues",
   "requirements": [
-    "backoff>=2.0"
+    "backoff~=2.0",
+    "aiolimiter~=1.0"
   ],
   "ssdp": [],
   "zeroconf": [],

requirements_test.txt

@@ -2,4 +2,5 @@ pytest~=7.1
 pytest-homeassistant-custom-component==0.12.18
 
 # Component dependencies
-backoff==2.2.1
+backoff~=2.0
+aiolimiter~=1.0

tests/conftest.py

@@ -15,6 +15,7 @@
 # See here for more info: https://docs.pytest.org/en/latest/fixture.html (note that
 # pytest includes fixtures OOB which you can use as defined on this page)
 from unittest.mock import patch
+from aiolimiter import AsyncLimiter
 
 import pytest
 
@@ -38,3 +39,8 @@ def skip_notifications_fixture():
         "homeassistant.components.persistent_notification.async_dismiss"
     ):
         yield
+
+@pytest.fixture(name="disable_api_rate_limiter", autouse=True)
+def disable_api_rate_limiter():
+    with patch("custom_components.candy.client._LIMITER"):
+        yield AsyncLimiter(max_rate=1000, time_period=1)