[rllib] Deprecate policy optimizers (#8345)

python/ray/tests/test_iter.py

@@ -29,18 +29,10 @@ def test_metrics(ray_start_regular_shared):
     it = it.gather_sync().for_each(f)
     it2 = it2.gather_sync().for_each(f)
 
-    # Context cannot be accessed outside the iterator.
-    with pytest.raises(ValueError):
-        LocalIterator.get_metrics()
-
     # Tests iterators have isolated contexts.
     assert it.take(4) == [1, 3, 6, 10]
     assert it2.take(4) == [1, 3, 6, 10]
 
-    # Context cannot be accessed outside the iterator.
-    with pytest.raises(ValueError):
-        LocalIterator.get_metrics()
-
 
 def test_zip_with_source_actor(ray_start_regular_shared):
     it = from_items([1, 2, 3, 4], num_shards=2)

python/ray/util/iter.py

@@ -670,15 +670,8 @@ class LocalIterator(Generic[T]):
 
     @contextmanager
     def _metrics_context(self):
-        if hasattr(self.thread_local, "metrics"):
-            prev_metrics = self.thread_local.metrics
-        else:
-            prev_metrics = None
-        try:
-            self.thread_local.metrics = self.shared_metrics.get()
-            yield
-        finally:
-            self.thread_local.metrics = prev_metrics
+        self.thread_local.metrics = self.shared_metrics.get()
+        yield
 
     def __iter__(self):
         self._build_once()