Randomness in interval and increasing waiting time to prevent API ban

main.py

@@ -1,4 +1,5 @@
 from tgtg import TgtgClient
+from tgtg.exceptions import TgtgAPIError
 import os
 import json
 import telegram
@@ -6,7 +7,16 @@ import asyncio
 import time
 import datetime
 import requests
+import random
 
+initial_waiting_time = 60
+waiting_time = initial_waiting_time
+waiting_time_limit = 60 * 60 * 24
+waiting_time_increase = 2
+
+randomness = 0.1
+
+interval = 60
 
 client = None
 telegram_bot = None
@@ -16,6 +26,21 @@ if removal_notification is None:
     removal_notification = False
 
 
+def parse_duration(seconds):
+    seconds = int(seconds)
+    minutes = seconds // 60
+    seconds = seconds % 60
+    hours = minutes // 60
+    minutes = minutes % 60
+
+    if hours > 0:
+        return f'{hours}h {minutes}m {seconds}s'
+    elif minutes > 0:
+        return f'{minutes}m {seconds}s'
+    else:
+        return f'{seconds}s'
+
+
 def check_env():
     if os.environ.get('TGTG_EMAIL') is None:
         return False
@@ -74,6 +99,7 @@ async def main():
     last = []
 
     while True:
+        try:
             items = client.get_items()
 
             texts = []
@@ -120,7 +146,18 @@ async def main():
                 print('-', end='', flush=True)
             
             last = next
-        time.sleep(60)
+            time.sleep(interval + randomness * interval * (2 * random.random() - 1))
+
+            waiting_time = initial_waiting_time
+
+        except TgtgAPIError as e:
+            print(e)
+            real_waiting_time = round(waiting_time + randomness * waiting_time * (2 * random.random() - 1))
+            await send_message([f'tg² failed to fetch data, retrying in {parse_duration(real_waiting_time)}'])
+            time.sleep(real_waiting_time)
+
+            if waiting_time < waiting_time_limit:
+                waiting_time *= waiting_time_increase
 
 if __name__ == '__main__':
     print('Check environ:', check_env())