More type annotations.

[python_utils.git] / smart_future.py

diff --git a/smart_future.py b/smart_future.py
index 8f23e7756b5417b15d89ba35c43dde971678ee14..1f6e6f0aedcf05966e536ec8f10f570c2175a3e4 100644 (file)
--- a/smart_future.py
+++ b/smart_future.py
@@ -3,7 +3,9 @@
 from __future__ import annotations
 import concurrent
 import concurrent.futures as fut
-from typing import Callable, List, TypeVar
+import logging
+import traceback
+from typing import Callable, List, Set, TypeVar
 
 from overrides import overrides
 
@@ -12,33 +14,68 @@ from overrides import overrides
 from deferred_operand import DeferredOperand
 import id_generator
 
+logger = logging.getLogger(__name__)
+
 T = TypeVar('T')
 
 
-def wait_any(futures: List[SmartFuture], *, callback: Callable = None):
+def wait_any(
+    futures: List[SmartFuture],
+    *,
+    callback: Callable = None,
+    log_exceptions: bool = True,
+):
     real_futures = []
     smart_future_by_real_future = {}
-    completed_futures = set()
-    for _ in futures:
-        real_futures.append(_.wrapped_future)
-        smart_future_by_real_future[_.wrapped_future] = _
+    completed_futures: Set[fut.Future] = set()
+    for x in futures:
+        assert type(x) == SmartFuture
+        real_futures.append(x.wrapped_future)
+        smart_future_by_real_future[x.wrapped_future] = x
+
     while len(completed_futures) != len(real_futures):
         newly_completed_futures = concurrent.futures.as_completed(real_futures)
         for f in newly_completed_futures:
             if callback is not None:
                 callback()
             completed_futures.add(f)
+            if log_exceptions and not f.cancelled():
+                exception = f.exception()
+                if exception is not None:
+                    logger.warning(
+                        f'Future {id(f)} raised an unhandled exception and exited.'
+                    )
+                    logger.exception(exception)
+                    raise exception
             yield smart_future_by_real_future[f]
     if callback is not None:
         callback()
     return
 
 
-def wait_all(futures: List[SmartFuture]) -> None:
-    real_futures = [x.wrapped_future for x in futures]
+def wait_all(
+    futures: List[SmartFuture],
+    *,
+    log_exceptions: bool = True,
+) -> None:
+    real_futures = []
+    for x in futures:
+        assert type(x) == SmartFuture
+        real_futures.append(x.wrapped_future)
+
     (done, not_done) = concurrent.futures.wait(
         real_futures, timeout=None, return_when=concurrent.futures.ALL_COMPLETED
     )
+    if log_exceptions:
+        for f in real_futures:
+            if not f.cancelled():
+                exception = f.exception()
+                if exception is not None:
+                    logger.warning(
+                        f'Future {id(f)} raised an unhandled exception and exited.'
+                    )
+                    logger.exception(exception)
+                    raise exception
     assert len(done) == len(real_futures)
     assert len(not_done) == 0
 
@@ -52,6 +89,7 @@ class SmartFuture(DeferredOperand):
     """
 
     def __init__(self, wrapped_future: fut.Future) -> None:
+        assert type(wrapped_future) == fut.Future
         self.wrapped_future = wrapped_future
         self.id = id_generator.get("smart_future_id")