MCOL-5806: added ability to start node in read-only mode

cmapi/cmapi_server/handlers/cluster.py

@@ -139,7 +139,10 @@ class ClusterHandler():
         return {'timestamp': operation_start_time}
 
     @staticmethod
-    def add_node(node: str, config: str = DEFAULT_MCS_CONF_PATH) -> dict:
+    def add_node(
+        node: str, config: str = DEFAULT_MCS_CONF_PATH,
+        read_only: bool = False,
+    ) -> dict:
         """Method to add node to MCS CLuster.
 
         :param node: node IP or name or FQDN
@@ -147,6 +150,8 @@ class ClusterHandler():
         :param config: columnstore xml config file path,
                        defaults to DEFAULT_MCS_CONF_PATH
         :type config: str, optional
+        :param read_only: add node in read-only mode, defaults to False
+        :type read_only: bool, optional
         :raises CMAPIBasicError: on exception while starting transaction
         :raises CMAPIBasicError: if transaction start isn't successful
         :raises CMAPIBasicError: on exception while adding node
@@ -157,20 +162,25 @@ class ClusterHandler():
         :rtype: dict
         """
         logger: logging.Logger = logging.getLogger('cmapi_server')
-        logger.debug(f'Cluster add node command called. Adding node {node}.')
+        logger.debug('Cluster add node command called. Adding node %s in %s mode.', node, 'read-only' if read_only else 'read-write')
 
         response = {'timestamp': str(datetime.now())}
 
         try:
             add_node(
                 node, input_config_filename=config,
-                output_config_filename=config
+                output_config_filename=config,
+                read_only=read_only,
             )
             if not get_dbroots(node, config):
-                add_dbroot(
-                    host=node, input_config_filename=config,
-                    output_config_filename=config
-                )
+                if not read_only:  # Read-only nodes don't own dbroots
+                    add_dbroot(
+                        host=node, input_config_filename=config,
+                        output_config_filename=config
+                    )
+                else:
+                    logger.debug("Node %s is read-only, skipping dbroot addition", node)
+
         except Exception as err:
             raise CMAPIBasicError('Error while adding node.') from err