[Bug]: Socket attribute typo in BaseAgent.__init__ causes silent broken-socket state

[diegoforni]

Bug Report

title: [Bug]: Socket attribute typo in BaseAgent.init causes silent broken-socket state

labels: bug

assignees: ondrej-lukas

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Bug Description

In netsecgame/agents/base_agent.py, the __init__ method contains a critical typo in its socket error handler. When socket.connect() raises a socket.error, the code sets:

self.sock = None   # <-- WRONG attribute name

instead of:

self._socket = None  # <-- correct attribute name used everywhere else

Because self.sock is a completely different (newly created) attribute, self._socket is never reset to None. It continues to hold the socket object that failed to connect. Every subsequent method (communicate, make_step, register, request_game_reset, terminate_connection, __del__) guards its socket usage with if self._socket:, which will evaluate to True even on a broken connection, silently attempting I/O on an unusable socket.

Impact:

• An agent that failed to connect appears fully initialized — the caller has no way to detect the failure.
• All subsequent communicate() / make_step() calls operate on a broken socket, causing unpredictable behavior: hangs waiting for data, BrokenPipeError, corrupted game state, or silent data loss — depending on OS-level socket behavior.
• The intended fallback (self._socket = None) to trigger safe-guards never fires.
• The ghost self.sock attribute pollutes the object namespace with a confusing, unused None value.

Affected file: netsecgame/agents/base_agent.py, line 25

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Steps to Reproduce

1. Instantiate BaseAgent (or any subclass) with an unreachable host/port:

   agent = BaseAgent("192.0.2.1", 9999, AgentRole.Attacker)  # port not open

2. Observe that no exception is raised and the agent object is returned.
3. Call agent.make_step(some_action) or agent.register().
4. The call blocks or raises an unexpected low-level socket error rather than failing cleanly.

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Expected Behavior

When the socket fails to connect, self._socket should be set to None. All subsequent method calls should then short-circuit cleanly (the if self._socket: guards would correctly prevent any I/O). Callers should be able to detect the failed state, e.g., by checking agent.socket is None.

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Fix

# netsecgame/agents/base_agent.py  (__init__)
        except socket.error as e:
            self._logger.error(f"Socket error: {e}")
-           self.sock = None        # BUG: wrong attribute name
+           self._socket = None     # FIX: matches the actual attribute

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Version

See VERSION file in repository root.

Installation / Deployment Method

Running locally from source