Update energycharts/tariff.py - add retry on timeout

packages/modules/electricity_tariffs/energycharts/tariff.py

@@ -1,29 +1,59 @@
+import logging
+import random
+import requests
+import time
 from typing import Dict
 from datetime import datetime, timedelta
-
 from helpermodules import timecheck
-
 from modules.common import req
 from modules.common.abstract_device import DeviceDescriptor
 from modules.common.component_state import TariffState
 from modules.electricity_tariffs.energycharts.config import EnergyChartsTariffConfiguration
 from modules.electricity_tariffs.energycharts.config import EnergyChartsTariff
 
+MAX_RETRIES = 10
+MAX_DELAY = 10
+log = logging.getLogger(__name__)
+
+
+def get_tomorrow_last_hour_timestamp() -> int:
+    tomorrow = datetime.now() + timedelta(days=2)
+    return int(tomorrow.timestamp())
+
 
-def fetch_prices(config: EnergyChartsTariffConfiguration) -> Dict[int, float]:
-    tomorrow = datetime.now() + timedelta(1)
+def create_request_url(config: EnergyChartsTariffConfiguration) -> str:
     start_time = timecheck.create_unix_timestamp_current_full_hour()
-    end_time = int(tomorrow.timestamp())
+    end_time = get_tomorrow_last_hour_timestamp()
     url = f'https://api.energy-charts.info/price?bzn={config.country}&start={start_time}&end={end_time}'
-    raw_prices = req.get_http_session().get(url).json()
-    price_arr = []
-    for price in raw_prices['price']:
-        price_arr.append((float(price + (config.surcharge*10))/1000000))  # €/MWh -> €/Wh + Aufschlag
+    log.debug("fetching tariffs: %s", url)
+    return url
+
+
+def parse_response(config: EnergyChartsTariffConfiguration, raw_prices: dict) -> Dict[str, float]:
     prices: Dict[int, float] = {}
-    prices = dict(zip([str(int(unix_seconds)) for unix_seconds in raw_prices['unix_seconds']], price_arr))
+    for timestamp, price_per_MWh in zip(raw_prices['unix_seconds'],  raw_prices['price']):
+        prices[str(int(timestamp))] = float(price_per_MWh + (config.surcharge*10))/1000000
+    log.debug("converted prices: %s : %s", len(prices), prices)
     return prices
 
 
+def fetch_prices(config: EnergyChartsTariffConfiguration) -> Dict[str, float]:
+    url = create_request_url(config)
+    for attempt in range(MAX_RETRIES):
+        attempt += 1  # one-based indexing
+        try:
+            response = req.get_http_session().get(url, timeout=(10, 20))
+            response.raise_for_status()
+            return parse_response(config, response.json())
+        except requests.exceptions.Timeout as e:
+            if MAX_RETRIES > attempt:
+                delay = (attempt) * random.uniform(attempt, MAX_DELAY)
+                log.warning(f"Timeout beim Abrufen der Preise (Versuch {attempt}/{MAX_RETRIES}) : {str(e)}"
+                            f", neuer Versuch in {delay:.1f} Sekunden...")
+                time.sleep(delay)
+    raise Exception("Timeout beim Abrufen der Preise nach {MAX_RETRIES} Versuchen")
+
+
 def create_electricity_tariff(config: EnergyChartsTariff):
     def updater():
         return TariffState(prices=fetch_prices(config.configuration))