hbc proper termination, hbd config reloadable

hbd/server/config.py

@@ -1,5 +1,6 @@
 """Configuration loader and defaults for hbd (HeartBeat Daemon/Server)."""
 
+import asyncio
 import logging
 import os
 
@@ -95,6 +96,91 @@ def load_config(path=None):
     return cfg
 
 
+class ReloadableConfig:
+    """Thread-safe/async-safe configuration wrapper that supports runtime reloading.
+    
+    This class wraps the configuration dictionary and provides:
+    - Thread-safe config reloading via SIGHUP
+    - Backward-compatible dict-like access
+    - Async lock to prevent concurrent reloads
+    """
+    
+    def __init__(self, initial_config, config_path=None):
+        """Initialize with initial configuration.
+        
+        Args:
+            initial_config: Initial configuration dictionary
+            config_path: Path to config file for reloading (optional)
+        """
+        self._config = initial_config
+        self._config_path = config_path
+        self._lock = asyncio.Lock()
+        self._logger = logging.getLogger(__name__)
+    
+    async def reload(self, config_path=None):
+        """Reload configuration from file.
+        
+        Args:
+            config_path: Path to config file (uses stored path if not provided)
+            
+        Returns:
+            New configuration dictionary
+            
+        Raises:
+            Exception if reload fails (keeps existing config)
+        """
+        path = config_path or self._config_path
+        if not path:
+            raise ValueError("No config path specified for reload")
+        
+        async with self._lock:
+            try:
+                # Load new config
+                new_config = load_config(path)
+                
+                # Store old config for rollback if needed
+                old_config = self._config
+                
+                # Update config
+                self._config = new_config
+                self._logger.info(f"Configuration reloaded from {path}")
+                
+                return new_config
+            except Exception as e:
+                self._logger.error(f"Failed to reload config from {path}: {e}", exc_info=True)
+                # Keep existing config on error
+                raise
+    
+    def get(self, key, default=None):
+        """Get a config value (dict-compatible)."""
+        return self._config.get(key, default)
+    
+    def __getitem__(self, key):
+        """Get a config value via subscript (dict-compatible)."""
+        return self._config[key]
+    
+    def __contains__(self, key):
+        """Check if key exists (dict-compatible)."""
+        return key in self._config
+    
+    def keys(self):
+        """Return config keys (dict-compatible)."""
+        return self._config.keys()
+    
+    def items(self):
+        """Return config items (dict-compatible)."""
+        return self._config.items()
+    
+    def values(self):
+        """Return config values (dict-compatible)."""
+        return self._config.values()
+    
+    @property
+    def config(self):
+        """Get the underlying config dict (for components that need full dict)."""
+        return self._config
+
+
 def get_watchhosts(config):
     """Extract watchhosts from config, supporting both new and legacy formats.