Refactor: Modularize configuration and implement robust DB bootstrap

app/db_sql.py

@@ -67,6 +67,36 @@ try:
 except Exception:
     log.exception('Could not connect to database.')
 
+def reconnect_db() -> bool:
+    """
+    Re-initializes the global database engine and connection using current settings.
+    Useful after bootstrapping new credentials from the 'cfg' table.
+    """
+    global engine, db, db_uri
+    
+    log.info("Refreshing database connection engine...")
+    try:
+        if engine:
+            engine.dispose()
+            log.info("Disposed of previous database engine.")
+            
+        db_uri = settings.SQLALCHEMY_DB_URI
+        engine = create_engine(
+            url = db_uri,
+            echo = False,
+            pool_use_lifo = True,
+            pool_pre_ping = True,
+            pool_recycle = settings.DB['pool_recycle'],
+            isolation_level = 'READ COMMITTED',
+            connect_args = {'connect_timeout': settings.DB['connect_timeout']}
+        )
+        db = engine.connect()
+        log.info(f"Database connection re-established successfully: {db_uri}")
+        return True
+    except Exception:
+        log.exception("FAILED to refresh database connection!")
+        return False
+
 # ### BEGIN ### API DB SQL ### sql_connect() ###
 @logger_reset
 def sql_connect(current_db, log_lvl: int = logging.INFO) -> None|bool|int: