Fix Excessive Writes (#258)

Author: alexyao2015

emulated_hue/__init__.py

@@ -52,6 +52,7 @@ async def async_start(self) -> None:
         """Start running the Hue emulation."""
         self._loop = asyncio.get_running_loop()
         self._hass = HomeAssistantClient(url=self._hass_url, token=self._hass_token)
+        await self.config.async_start(self._loop)
         await self._hass.connect()
         await self._api.async_setup()
         self.loop.create_task(async_setup_discovery(self.config))
@@ -63,5 +64,6 @@ async def async_start(self) -> None:
     async def async_stop(self) -> None:
         """Stop running the Hue emulation."""
         LOGGER.info("Application shutdown")
+        await self.config.async_stop()
         await self._hass.disconnect()
         await self._api.async_stop()

emulated_hue/config.py

@@ -1,4 +1,5 @@
 """Hold configuration variables for the emulated hue bridge."""
+import asyncio
 import datetime
 import hashlib
 import logging
@@ -7,6 +8,7 @@
 
 from getmac import get_mac_address
 
+from .const import CONFIG_WRITE_INTERVAL_SECONDS
 from .utils import async_save_json, create_secure_string, get_local_ip, load_json
 
 if TYPE_CHECKING:
@@ -76,6 +78,29 @@ def __init__(
         self._bridge_serial = mac_str.lower()
         self._bridge_uid = f"2f402f80-da50-11e1-9b23-{mac_str}"
 
+        # Flag to initiate shutdown of background saving
+        self._interrupted = False
+        self._need_save = False
+        self._saver_task = None  # type: asyncio.Task | None
+
+    async def _background_saver(self) -> None:
+        last_save = 0
+        while not self._interrupted:
+            now = datetime.datetime.now().timestamp()
+            if self._need_save and now - last_save > CONFIG_WRITE_INTERVAL_SECONDS:
+                await async_save_json(self.get_path(CONFIG_FILE), self._config)
+                last_save = now
+            await asyncio.sleep(1)
+
+    async def async_start(self, loop: asyncio.AbstractEventLoop) -> None:
+        """Start background saving task."""
+        self._saver_task = loop.create_task(self._background_saver())
+
+    async def async_stop(self) -> None:
+        """Save the config."""
+        self._interrupted = True
+        await self._saver_task
+
     @property
     def ip_addr(self) -> str:
         """Return ip address of the emulated bridge."""
@@ -252,7 +277,7 @@ async def async_set_storage_value(
             needs_save = True
         # save config to file if changed
         if needs_save:
-            await async_save_json(self.get_path(CONFIG_FILE), self._config)
+            self._need_save = True
 
     async def async_delete_storage_value(self, key: str, subkey: str = None) -> None:
         """Delete a value in persistent storage."""

emulated_hue/const.py

@@ -2,6 +2,8 @@
 
 DEFAULT_THROTTLE_MS = 0
 
+CONFIG_WRITE_INTERVAL_SECONDS = 60
+
 HASS_ATTR_BRIGHTNESS = "brightness"
 HASS_ATTR_COLOR_TEMP = "color_temp"
 HASS_ATTR_XY_COLOR = "xy_color"