Copy missing values from INIT_CFG to config_db during db_migration

config/main.py

@@ -838,7 +838,7 @@ def reload(filename, yes, load_sysinfo, no_service_restart):
         log.log_info("'reload' stopping services...")
         _stop_services()
 
-    # In Single AISC platforms we have single DB service. In multi-ASIC platforms we have a global DB
+    # In Single ASIC platforms we have single DB service. In multi-ASIC platforms we have a global DB
     # service running in the host + DB services running in each ASIC namespace created per ASIC.
     # In the below logic, we get all namespaces in this platform and add an empty namespace ''
     # denoting the current namespace which we are in ( the linux host )

scripts/db_migrator.py

@@ -2,6 +2,7 @@
 
 import os
 import argparse
+import json
 import sys
 import traceback
 
@@ -19,7 +20,7 @@
 except KeyError:
     pass
 
-
+INIT_CFG_FILE = '/etc/sonic/init_cfg.json'
 SYSLOG_IDENTIFIER = 'db_migrator'
 
 # Global logger instance
@@ -254,6 +255,24 @@ def set_version(self, version=None):
         self.configDB.set_entry(self.TABLE_NAME, self.TABLE_KEY, entry)
 
 
+    def common_migration_ops(self):
+        try:
+            with open(INIT_CFG_FILE) as f:
+                init_db = json.load(f)
+        except Exception as e:
+            raise Exception(str(e))
+
+        for init_cfg_table, table_val in init_db.items():
+            data = self.configDB.get_table(init_cfg_table)
+            if data:
+                # Ignore overriding the values that pre-exist in configDB
+                continue
+            log.log_info("Migrating table {} from INIT_CFG to config_db".format(init_cfg_table))
+            # Update all tables that do not exist in configDB but are present in INIT_CFG
+            for init_table_key, init_table_val in table_val.items():
+                self.configDB.set_entry(init_cfg_table, init_table_key, init_table_val)
+
+
     def migrate(self):
         version = self.get_version()
         log.log_info('Upgrading from version ' + version)
@@ -262,6 +281,8 @@ def migrate(self):
             if next_version == version:
                 raise Exception('Version migrate from %s stuck in same version' % version)
             version = next_version
+        # Perform common migration ops
+        self.common_migration_ops()
 
 
 def main():

sonic-utilities-tests/db_migrator_test.py

@@ -1,3 +1,4 @@
+import mock
 import os
 import pytest
 import sys
@@ -61,12 +62,13 @@ def test_mellanox_buffer_migrator_negative_cold_reboot(self, scenario):
         db_after_migrate = scenario + '-expected'
         device_info.get_sonic_version_info = get_sonic_version_info_mlnx
         _ = self.mock_dedicated_config_db(db_before_migrate)
-        import db_migrator
-        dbmgtr = db_migrator.DBMigrator(None)
-        dbmgtr.migrate()
-        expected_db = self.mock_dedicated_config_db(db_after_migrate)
-        self.check_config_db(dbmgtr.configDB, expected_db.cfgdb)
-        assert not dbmgtr.mellanox_buffer_migrator.is_buffer_config_default
+        with mock.patch("db_migrator.DBMigrator.common_migration_ops"):
+            import db_migrator
+            dbmgtr = db_migrator.DBMigrator(None)
+            dbmgtr.migrate()
+            expected_db = self.mock_dedicated_config_db(db_after_migrate)
+            self.check_config_db(dbmgtr.configDB, expected_db.cfgdb)
+            assert not dbmgtr.mellanox_buffer_migrator.is_buffer_config_default
 
     @pytest.mark.parametrize('sku_version',
                              [('ACS-MSN2700', 'version_1_0_1'),
@@ -97,10 +99,11 @@ def test_mellanox_buffer_migrator_for_cold_reboot(self, sku_version, topo):
         # migration from any version between start_version and the current version (inclusive) to the current version will be verified
         for version in self.version_list[start_index:]:
             _ = self.mock_dedicated_config_db(self.make_db_name_by_sku_topo_version(sku, topo, version))
-            import db_migrator
-            dbmgtr = db_migrator.DBMigrator(None)
-            dbmgtr.migrate()
-            self.check_config_db(dbmgtr.configDB, expected_db.cfgdb)
-            assert dbmgtr.mellanox_buffer_migrator.is_buffer_config_default
+            with mock.patch("db_migrator.DBMigrator.common_migration_ops"):
+                import db_migrator
+                dbmgtr = db_migrator.DBMigrator(None)
+                dbmgtr.migrate()
+                self.check_config_db(dbmgtr.configDB, expected_db.cfgdb)
+                assert dbmgtr.mellanox_buffer_migrator.is_buffer_config_default
 
         self.clear_dedicated_mock_dbs()