Update the DBmigrator to support persistent loglevel during warm-upgrade (sonic-net#2370)

- What I did
Add the ability to the user to save the loglevel and make it persistent to reboot with the support in warm-upgrade. (Not need to add special support for cold/fast reboot since the LOGLEVEL DB flushes during fast/cold reboot).

- How I did it
Add a new version to the db_migrator that will move the logger tables from the LOGLEVEL DB to the CONFIG DB

- How to verify it
1. start with a switch that has an old master image (old master means that the VERSION in the config db is 3_0_5 or lower)
2. install this image to the switch
3. run warm-reboot
4. verify that the LOGLEVEL DB does not contain logger tables -> run redis-cli -n 3 keys "*" (expect to see only the JINJA2CACHE)
5. verify that the logger tables are in the config db -> run redis-cli -n 4 keys "LOGGER|*"

Author: EdenGri

scripts/db_migrator.py

@@ -44,7 +44,7 @@ def __init__(self, namespace, socket=None):
                      none-zero values.
               build: sequentially increase within a minor version domain.
         """
-        self.CURRENT_VERSION = 'version_3_0_5'
+        self.CURRENT_VERSION = 'version_3_0_6'
 
         self.TABLE_NAME      = 'VERSIONS'
         self.TABLE_KEY       = 'DATABASE'
@@ -70,6 +70,10 @@ def __init__(self, namespace, socket=None):
         if self.stateDB is not None:
             self.stateDB.connect(self.stateDB.STATE_DB)
 
+        self.loglevelDB = SonicV2Connector(host='127.0.0.1')
+        if self.loglevelDB is not None:
+            self.loglevelDB.connect(self.loglevelDB.LOGLEVEL_DB)
+
         version_info = device_info.get_sonic_version_info()
         asic_type = version_info.get('asic_type')
         self.asic_type = asic_type
@@ -717,9 +721,36 @@ def version_3_0_4(self):
 
     def version_3_0_5(self):
         """
-        Current latest version. Nothing to do here.
+        Version 3_0_5
         """
         log.log_info('Handling version_3_0_5')
+        # Removing LOGLEVEL DB and moving it's content to CONFIG DB
+        # Removing Jinja2_cache
+        warmreboot_state = self.stateDB.get(self.stateDB.STATE_DB, 'WARM_RESTART_ENABLE_TABLE|system', 'enable')
+        if warmreboot_state == 'true':
+            table_name = "LOGGER"
+            loglevel_field = "LOGLEVEL"
+            logoutput_field = "LOGOUTPUT"
+            keys = self.loglevelDB.keys(self.loglevelDB.LOGLEVEL_DB, "*")
+            if keys is not None:
+                for key in keys:
+                    if key != "JINJA2_CACHE":
+                        fvs = self.loglevelDB.get_all(self.loglevelDB.LOGLEVEL_DB, key)
+                        component = key.split(":")[1]
+                        loglevel = fvs[loglevel_field]
+                        logoutput = fvs[logoutput_field]
+                        self.configDB.set(self.configDB.CONFIG_DB, '{}|{}'.format(table_name, component), loglevel_field, loglevel)
+                        self.configDB.set(self.configDB.CONFIG_DB, '{}|{}'.format(table_name, component), logoutput_field, logoutput)
+                    self.loglevelDB.delete(self.loglevelDB.LOGLEVEL_DB, key)
+        self.set_version('version_3_0_6')
+        return 'version_3_0_6'
+
+    def version_3_0_6(self):
+        """
+        Current latest version. Nothing to do here.
+        """
+
+        log.log_info('Handling version_3_0_6')
         return None
 
     def get_version(self):

tests/db_migrator_input/config_db/logger_tables_expected.json

@@ -0,0 +1,13 @@
+{
+    "VERSIONS|DATABASE": {
+        "VERSION": "version_3_0_6"
+    },
+    "LOGGER|orchagent": {
+        "LOGLEVEL": "INFO",
+        "LOGOUTPUT": "SYSLOG"
+    },
+    "LOGGER|SAI_API_BUFFER": {
+        "LOGLEVEL": "SAI_LOG_LEVEL_NOTICE",
+        "LOGOUTPUT": "SYSLOG"
+    }
+}

tests/db_migrator_input/config_db/logger_tables_input.json

@@ -0,0 +1,5 @@
+{
+    "VERSIONS|DATABASE": {
+        "VERSION": "version_3_0_5"
+    }
+}

tests/db_migrator_input/config_db/reclaiming-buffer-warmreboot-expected.json

@@ -2043,6 +2043,6 @@
         "admin_status": "up"
     },
     "VERSIONS|DATABASE": {
-        "VERSION": "version_3_0_5"
+        "VERSION": "version_3_0_3"
     }
 }

tests/db_migrator_input/loglevel_db/logger_tables_input.json

@@ -0,0 +1,11 @@
+{
+    "orchagent:orchagent": {
+        "LOGLEVEL": "INFO",
+        "LOGOUTPUT": "SYSLOG"
+    },
+    "SAI_API_BUFFER:SAI_API_BUFFER": {
+        "LOGLEVEL": "SAI_LOG_LEVEL_NOTICE",
+        "LOGOUTPUT": "SYSLOG"
+    },
+    "JINJA2_CACHE": {}
+}

tests/db_migrator_test.py

@@ -409,4 +409,44 @@ def test_global_dscp_to_tc_map_migrator(self):
         dbmgtr_mlnx.migrate()
         resulting_table = dbmgtr_mlnx.configDB.get_table('PORT_QOS_MAP')
         assert resulting_table == {}
+        
+class TestMoveLoggerTablesInWarmUpgrade(object):
+    @classmethod
+    def setup_class(cls):
+        os.environ['UTILITIES_UNIT_TESTING'] = "2"
+
+    @classmethod
+    def teardown_class(cls):
+        os.environ['UTILITIES_UNIT_TESTING'] = "0"
+        dbconnector.dedicated_dbs['CONFIG_DB'] = None
+        dbconnector.dedicated_dbs['LOGLEVEL_DB'] = None
+        dbconnector.dedicated_dbs['STATE_DB'] = None
+
+    def mock_dedicated_loglevel_db(self, filename):
+        jsonfile = os.path.join(mock_db_path, 'loglevel_db', filename)
+        dbconnector.dedicated_dbs['LOGLEVEL_DB'] = jsonfile
+        loglevel_db = SonicV2Connector(host='127.0.0.1')
+        loglevel_db.connect(loglevel_db.LOGLEVEL_DB)
+        return loglevel_db
+
+    def test_move_logger_tables_in_warm_upgrade(self):
+        device_info.get_sonic_version_info = get_sonic_version_info_mlnx
 
+        dbconnector.dedicated_dbs['CONFIG_DB'] = os.path.join(mock_db_path, 'config_db', 'logger_tables_input')
+        dbconnector.dedicated_dbs['LOGLEVEL_DB'] = os.path.join(mock_db_path, 'loglevel_db', 'logger_tables_input')
+        dbconnector.dedicated_dbs['STATE_DB'] = os.path.join(mock_db_path, 'state_db')
+
+        import db_migrator
+        dbmgtr = db_migrator.DBMigrator(None)
+        dbmgtr.migrate()
+
+        dbconnector.dedicated_dbs['CONFIG_DB'] = os.path.join(mock_db_path, 'config_db', 'logger_tables_expected')
+        dbconnector.dedicated_dbs['LOGLEVEL_DB'] = os.path.join(mock_db_path, 'loglevel_db', 'logger_tables_expected')
+
+        expected_db = Db()
+
+        resulting_table = dbmgtr.configDB.get_table('LOGGER')
+        expected_table = expected_db.cfgdb.get_table('LOGGER')
+
+        diff = DeepDiff(resulting_table, expected_table, ignore_order=True)
+        assert not diff