Target closed exception on env.close()

[bwitherspoon]

Running the example:

from gym_derk.envs import DerkEnv

env = DerkEnv(
  n_arenas=1 # Change to 100 for instance, to run many instances in parallel
)

observation_n = env.reset()

while True:
  # Take random actions each step
  action_n = [env.action_space.sample() for i in range(env.n_agents)]
  observation_n, reward_n, done_n, info_n = env.step(action_n)

  if all(done_n):
    break
env.close()

I get the following exception on env.close():

Traceback (most recent call last):
  File "test.py", line 16, in <module>
    env.close()
  File "/home/spoonb/.conda/envs/derk/lib/python3.8/site-packages/gym_derk/envs/derk_env.py", line 193, in close
    return asyncio.get_event_loop().run_until_complete(self.async_close())
  File "/home/spoonb/.conda/envs/derk/lib/python3.8/asyncio/base_events.py", line 616, in run_until_complete
    return future.result()
  File "/home/spoonb/.conda/envs/derk/lib/python3.8/site-packages/gym_derk/envs/derk_env.py", line 205, in async_close
    await self.running_session
  File "/home/spoonb/.conda/envs/derk/lib/python3.8/site-packages/gym_derk/derk_app_instance.py", line 264, in run_episodes_loop
    await self.page.evaluate('''() => window.derk.session.runEpisodesLoop()''')
  File "/home/spoonb/.conda/envs/derk/lib/python3.8/site-packages/pyppeteer/page.py", line 1184, in evaluate
    return await frame.evaluate(pageFunction, *args, force_expr=force_expr)
  File "/home/spoonb/.conda/envs/derk/lib/python3.8/site-packages/pyppeteer/frame_manager.py", line 308, in evaluate
    return await context.evaluate(
  File "/home/spoonb/.conda/envs/derk/lib/python3.8/site-packages/pyppeteer/execution_context.py", line 53, in evaluate
    handle = await self.evaluateHandle(
  File "/home/spoonb/.conda/envs/derk/lib/python3.8/site-packages/pyppeteer/execution_context.py", line 108, in evaluateHandle
    _rewriteError(e)
  File "/home/spoonb/.conda/envs/derk/lib/python3.8/site-packages/pyppeteer/execution_context.py", line 238, in _rewriteError
    raise error
  File "/home/spoonb/.conda/envs/derk/lib/python3.8/site-packages/pyppeteer/execution_context.py", line 99, in evaluateHandle
    _obj = await self._client.send('Runtime.callFunctionOn', {
pyppeteer.errors.NetworkError: Protocol error Runtime.callFunctionOn: Target closed.

[FredrikNoren]

@bwitherspoon Thanks for reporting. From what I can tell, everything should still be working fine, this is just a "cosmetic" error on the env.close call (i.e. everything should still work fine). I'll look into fixing it.

[FredrikNoren]

Ok, this is now fixed in 0.15.6