Merged PR 394: Fix 'too many open files'

## Summary
Add a method to PCAP to clear file handlers. Invoke this method while resetting environment.

## Test process
no longer crashes on windows when i run too many episodes

## Checklist
- [x] PR is linked to a **work item**
- [x] **acceptance criteria** of linked ticket are met
- [x] performed **self-review** of the code
- [n] written **tests** for any new functionality added with this PR
- [n] updated the **documentation** if this PR changes or adds functionality
- [n] written/updated **design docs** if this PR implements new functionality
- [n] updated the **change log**
- [x] ran **pre-commit** checks for code style
- [x] attended to any **TO-DOs** left in the code

Related work items: #2588, #2626

src/primaite/session/environment.py

@@ -11,6 +11,7 @@ from primaite.game.game import PrimaiteGame
 from primaite.session.episode_schedule import build_scheduler, EpisodeScheduler
 from primaite.session.io import PrimaiteIO
 from primaite.simulator import SIM_OUTPUT
+from primaite.simulator.system.core.packet_capture import PacketCapture
 
 _LOGGER = getLogger(__name__)
 
@@ -92,6 +93,7 @@ class PrimaiteGymEnv(gymnasium.Env):
             all_agent_actions = {name: agent.action_history for name, agent in self.game.agents.items()}
             self.io.write_agent_actions(agent_actions=all_agent_actions, episode=self.episode_counter)
         self.episode_counter += 1
+        PacketCapture.clear()
         self.game: PrimaiteGame = PrimaiteGame.from_config(cfg=self.episode_scheduler(self.episode_counter))
         self.game.setup_for_episode(episode=self.episode_counter)
         state = self.game.get_sim_state()

src/primaite/session/ray_envs.py

@@ -11,6 +11,7 @@ from primaite.session.environment import _LOGGER, PrimaiteGymEnv
 from primaite.session.episode_schedule import build_scheduler, EpisodeScheduler
 from primaite.session.io import PrimaiteIO
 from primaite.simulator import SIM_OUTPUT
+from primaite.simulator.system.core.packet_capture import PacketCapture
 
 
 class PrimaiteRayMARLEnv(MultiAgentEnv):
@@ -63,6 +64,7 @@ class PrimaiteRayMARLEnv(MultiAgentEnv):
             self.io.write_agent_actions(agent_actions=all_agent_actions, episode=self.episode_counter)
 
         self.episode_counter += 1
+        PacketCapture.clear()
         self.game: PrimaiteGame = PrimaiteGame.from_config(self.episode_scheduler(self.episode_counter))
         self.game.setup_for_episode(episode=self.episode_counter)
         state = self.game.get_sim_state()

src/primaite/simulator/system/core/packet_capture.py

@@ -21,6 +21,8 @@ class PacketCapture:
     The PCAPs are logged to: <simulation output directory>/<hostname>/<hostname>_<ip address>_pcap.log
     """
 
+    _logger_instances: List[logging.Logger] = []
+
     def __init__(
         self,
         hostname: str,
@@ -65,10 +67,12 @@ class PacketCapture:
 
         if outbound:
             self.outbound_logger = logging.getLogger(self._get_logger_name(outbound))
+            PacketCapture._logger_instances.append(self.outbound_logger)
             logger = self.outbound_logger
         else:
             self.inbound_logger = logging.getLogger(self._get_logger_name(outbound))
             logger = self.inbound_logger
+            PacketCapture._logger_instances.append(self.inbound_logger)
 
         logger.setLevel(60)  # Custom log level > CRITICAL to prevent any unwanted standard DEBUG-CRITICAL logs
         logger.addHandler(file_handler)
@@ -122,3 +126,13 @@ class PacketCapture:
         if SIM_OUTPUT.save_pcap_logs:
             msg = frame.model_dump_json()
             self.outbound_logger.log(level=60, msg=msg)  # Log at custom log level > CRITICAL
+
+    @staticmethod
+    def clear():
+        """Close all open PCAP file handlers."""
+        for logger in PacketCapture._logger_instances:
+            handlers = logger.handlers[:]
+            for handler in handlers:
+                logger.removeHandler(handler)
+                handler.close()
+        PacketCapture._logger_instances = []