monitor.py: Still write manifest if close errors

Before, on a headless server I was losing manifests with:

NullFunctionError: Attempt to call an undefined function glIsFramebuffer, check for bool(glIsFramebuffer) before calling (when closing Ant-v0)

gym/monitoring/monitor.py

@@ -155,14 +155,14 @@ class Monitor(object):
         # during video recording.
         try:
             self.env.render(close=True)
-        except Exception:
-            type, value, traceback = sys.exc_info()
+        except Exception as e:
             if self.env.spec:
                 key = self.env.spec.id
             else:
                 key = self.env
-            # This likely indicates unsupported kwargs
-            six.reraise(type, '{} (when closing {})'.format(value, key), traceback)
+            # We don't want to avoid writing the manifest simply
+            # because we couldn't close the renderer.
+            logger.warn('Could not close renderer for %s: %s'.format(key, e))
 
         # Give it a very distiguished name, since we need to pick it
         # up from the filesystem later.

gym/monitoring/tests/test_monitor.py

@@ -0,0 +1,36 @@
+import contextlib
+import glob
+import os
+import shutil
+import tempfile
+
+import gym
+from gym.monitoring import monitor
+
+class FakeEnv(gym.Env):
+    def _render(self, close=True):
+        raise RuntimeError('Raising')
+
+@contextlib.contextmanager
+def tempdir():
+    temp = tempfile.mkdtemp()
+    yield temp
+    shutil.rmtree(temp)
+
+def test_monitor_filename():
+    with tempdir() as temp:
+        env = gym.make('Acrobot-v0')
+        env.monitor.start(temp)
+        env.monitor.close()
+
+        manifests = glob.glob(os.path.join(temp, '*.manifest.*'))
+        assert len(manifests) == 1
+
+def test_close_monitor():
+    with tempdir() as temp:
+        env = FakeEnv()
+        env.monitor.start(temp)
+        env.monitor.close()
+
+        manifests = monitor.detect_training_manifests(temp)
+        assert len(manifests) == 1