Merge pull request #159 from andyguenin/periodic_exception

Propogate exceptions that are called in periodic

aat/engine/dispatch/periodic.py

@@ -1,4 +1,5 @@
 import asyncio
+from asyncio import Future
 from datetime import datetime
 from typing import Awaitable, Callable, List, Optional
 
@@ -47,10 +48,12 @@ def expires(self, timestamp: datetime) -> bool:
             return False
         return should_expire(self._last, timestamp, self.second, self.minute, self.hour)
 
-    async def execute(self, timestamp: datetime) -> None:
+    async def execute(self, timestamp: datetime) -> Optional[Future]:
         if self.expires(timestamp):
-            asyncio.ensure_future(self._function(timestamp=timestamp))
             self._last = timestamp
+            return asyncio.ensure_future(self._function(timestamp=timestamp))
+        else:
+            return None
 
 
 class PeriodicManagerMixin(object):

aat/engine/engine.py

@@ -424,14 +424,18 @@ async def run(self) -> None:
                     await self.processEvent(event, strat)
 
                 # process any periodics
-                await asyncio.gather(
+                periodic_result = await asyncio.gather(
                     *(
                         asyncio.create_task(p.execute(self._latest))
                         for p in self.manager.periodics()
                         if p.expires(self._latest)
                     )
                 )
 
+                exceptions = [r for r in periodic_result if r.exception()]
+                if any(exceptions):
+                    raise exceptions[0].exception()
+
         # Before engine shutdown, send an exit event
         await self.processEvent(Event(type=EventType.EXIT, target=None))