DPE-3830 - Paxos single leader (#416)

* testing paxos single leader

* fix utest

* test fix

Author: paulomach

lib/charms/mysql/v0/mysql.py

@@ -134,7 +134,7 @@ def wait_until_mysql_connection(self) -> None:
 # Increment this major API version when introducing breaking changes
 LIBAPI = 0
 
-LIBPATCH = 86
+LIBPATCH = 87
 
 UNIT_TEARDOWN_LOCKNAME = "unit-teardown"
 UNIT_ADD_LOCKNAME = "unit-add"
@@ -1023,6 +1023,7 @@ def render_mysqld_configuration(  # noqa: C901
             "log_error": f"{snap_common}/var/log/mysql/error.log",
             "general_log": "OFF",
             "general_log_file": f"{snap_common}/var/log/mysql/general.log",
+            "loose-group_replication_paxos_single_leader": "ON",
             "slow_query_log_file": f"{snap_common}/var/log/mysql/slow.log",
             "binlog_expire_logs_seconds": f"{binlog_retention_seconds}",
             "loose-audit_log_policy": audit_log_policy.upper(),

tests/unit/test_mysql.py

@@ -2088,6 +2088,7 @@ def test_render_mysqld_configuration(self, _get_available_memory):
             "loose-audit_log_policy": "LOGINS",
             "loose-audit_log_strategy": "ASYNCHRONOUS",
             "loose-audit_log_file": "/var/log/mysql/audit.log",
+            "loose-group_replication_paxos_single_leader": "ON",
             "innodb_buffer_pool_chunk_size": "2902458368",
             "gtid_mode": "ON",
             "enforce_gtid_consistency": "ON",

tests/unit/test_mysqlsh_helpers.py

@@ -327,6 +327,7 @@ def test_write_mysqld_config(
             "log_error = /var/snap/charmed-mysql/common/var/log/mysql/error.log",
             "general_log = OFF",
             "general_log_file = /var/snap/charmed-mysql/common/var/log/mysql/general.log",
+            "loose-group_replication_paxos_single_leader = ON",
             "slow_query_log_file = /var/snap/charmed-mysql/common/var/log/mysql/slow.log",
             "binlog_expire_logs_seconds = 604800",
             "loose-audit_log_policy = LOGINS",
@@ -364,6 +365,7 @@ def test_write_mysqld_config(
             "log_error = /var/snap/charmed-mysql/common/var/log/mysql/error.log",
             "general_log = OFF",
             "general_log_file = /var/snap/charmed-mysql/common/var/log/mysql/general.log",
+            "loose-group_replication_paxos_single_leader = ON",
             "slow_query_log_file = /var/snap/charmed-mysql/common/var/log/mysql/slow.log",
             "binlog_expire_logs_seconds = 604800",
             "loose-audit_log_policy = LOGINS",