restart powermate after exceptions from sleep

.gitignore

@@ -1 +1,2 @@
 __pycache__/
+tags

powermate_pactl.py

@@ -2,11 +2,13 @@
 
 
 import glob
+import time
 
 from lib.powermate import powermate
 from lib.python_pulse_control.pulsectl import pulsectl
 
 
+RETRY_ATTEMPTS = 10
 INCREASE_AMOUNT = 0.01
 
 
@@ -17,8 +19,6 @@ class PowerMate(powermate.PowerMateBase):
         super().__init__(path)
 
     def rotate(self, rotation):
-        #print(rotation);
-
         if (rotation > 0):
             self.change_vol(INCREASE_AMOUNT)
         else:
@@ -26,10 +26,36 @@ class PowerMate(powermate.PowerMateBase):
 
     def change_vol(self, vol):
         for sink in self.pulse.sink_list():
-            #print(sink)
             self.pulse.volume_change_all_chans(sink, vol)
 
+def start():
+    for i in range(1, RETRY_ATTEMPTS + 1):
+        path = ''
+        powermates = glob.glob('/dev/input/by-id/*PowerMate*')
+
+        if len(powermates) > 0 :
+            path = powermates[0]
+            print(f'found powermate at {path}')
+
+        if path:
+            pm = PowerMate(path)
+
+            try:
+                pm.run()
+            except (KeyboardInterrupt, SystemExit):
+                return
+            except Exception as e:
+                print(f'caught exception from AsyncFileEventDispatcher.run(): {e}')
+                print('attempting restart')
+                time.sleep(5) # NOTE: give time to enumerate USB after suspend
+                start()
+                return
+        elif i == 1:
+            print(f'waiting up to {RETRY_ATTEMPTS}s for powermate')
+        elif i == RETRY_ATTEMPTS:
+            print(f'giving up looking for powermate after {RETRY_ATTEMPTS}s')
+
+        time.sleep(1)
 
 if __name__ == '__main__':
-    pm = PowerMate(glob.glob('/dev/input/by-id/*PowerMate*')[0])
+    start()
-    pm.run()