def render_config(hosts=None):
    if hosts is None:
        hosts = []

    config_file = resolve_cnf_file()
    if not os.path.exists(os.path.dirname(config_file)):
        os.makedirs(os.path.dirname(config_file))

    context = {
        'cluster_name': 'juju_cluster',
        'private_address': get_cluster_host_ip(),
        'cluster_hosts': ",".join(hosts),
        'sst_method': config('sst-method'),
        'sst_password': sst_password(),
        'innodb_file_per_table': config('innodb-file-per-table'),
        'table_open_cache': config('table-open-cache'),
        'lp1366997_workaround': config('lp1366997-workaround'),
        'binlogs_path': config('binlogs-path'),
        'enable_binlogs': config('enable-binlogs'),
        'binlogs_max_size': config('binlogs-max-size'),
        'binlogs_expire_days': config('binlogs-expire-days'),
        'performance_schema': config('performance-schema'),
        'is_leader': is_leader(),
        'server_id': get_server_id(),
    }

    if config('prefer-ipv6'):
        # NOTE(hopem): this is a kludge to get percona working with ipv6.
        # See lp 1380747 for more info. This is intended as a stop gap until
        # percona package is fixed to support ipv6.
        context['bind_address'] = '::'
        context['ipv6'] = True
    else:
        context['ipv6'] = False

    wsrep_provider_options = get_wsrep_provider_options()
    if wsrep_provider_options:
        context['wsrep_provider_options'] = wsrep_provider_options

    if CompareHostReleases(lsb_release()['DISTRIB_CODENAME']) < 'bionic':
        # myisam_recover is not valid for PXC 5.7 (introduced in Bionic) so we
        # only set it for PXC 5.6.
        context['myisam_recover'] = 'BACKUP'
        context['wsrep_provider'] = '/usr/lib/libgalera_smm.so'
    elif CompareHostReleases(lsb_release()['DISTRIB_CODENAME']) >= 'bionic':
        context['wsrep_provider'] = '/usr/lib/galera3/libgalera_smm.so'
        context['default_storage_engine'] = 'InnoDB'
        context['wsrep_log_conflicts'] = True
        context['innodb_autoinc_lock_mode'] = '2'
        context['pxc_strict_mode'] = config('pxc-strict-mode')

    context.update(PerconaClusterHelper().parse_config())
    render(os.path.basename(config_file), config_file, context, perms=0o444)
def render_config(hosts=None):
    if hosts is None:
        hosts = []

    config_file = resolve_cnf_file()
    if not os.path.exists(os.path.dirname(config_file)):
        os.makedirs(os.path.dirname(config_file))

    context = {
        'cluster_name': 'juju_cluster',
        'private_address': get_cluster_host_ip(),
        'cluster_hosts': ",".join(hosts),
        'sst_method': config('sst-method'),
        'sst_password': sst_password(),
        'innodb_file_per_table': config('innodb-file-per-table'),
        'table_open_cache': config('table-open-cache'),
        'binlogs_path': config('binlogs-path'),
        'enable_binlogs': config('enable-binlogs'),
        'binlogs_max_size': config('binlogs-max-size'),
        'binlogs_expire_days': config('binlogs-expire-days'),
        'performance_schema': config('performance-schema'),
        'is_leader': is_leader(),
        'server_id': get_server_id(),
        'series_upgrade': is_unit_upgrading_set(),
    }

    if config('prefer-ipv6'):
        # NOTE(hopem): this is a kludge to get percona working with ipv6.
        # See lp 1380747 for more info. This is intended as a stop gap until
        # percona package is fixed to support ipv6.
        context['bind_address'] = '::'
        context['ipv6'] = True
    else:
        context['ipv6'] = False

    wsrep_provider_options = get_wsrep_provider_options()
    if wsrep_provider_options:
        context['wsrep_provider_options'] = wsrep_provider_options

    if config('wsrep-slave-threads') is not None:
        context['wsrep_slave_threads'] = config('wsrep-slave-threads')

    if CompareHostReleases(lsb_release()['DISTRIB_CODENAME']) < 'bionic':
        # myisam_recover is not valid for PXC 5.7 (introduced in Bionic) so we
        # only set it for PXC 5.6.
        context['myisam_recover'] = 'BACKUP'
        context['wsrep_provider'] = '/usr/lib/libgalera_smm.so'
        if 'wsrep_slave_threads' not in context:
            context['wsrep_slave_threads'] = 1
    elif CompareHostReleases(lsb_release()['DISTRIB_CODENAME']) >= 'bionic':
        context['wsrep_provider'] = '/usr/lib/galera3/libgalera_smm.so'
        context['default_storage_engine'] = 'InnoDB'
        context['wsrep_log_conflicts'] = True
        context['innodb_autoinc_lock_mode'] = '2'
        context['pxc_strict_mode'] = config('pxc-strict-mode')
        if 'wsrep_slave_threads' not in context:
            context['wsrep_slave_threads'] = 48

    if config('databases-to-replicate'):
        context['databases_to_replicate'] = get_databases_to_replicate()

    context['server-id'] = get_server_id()

    context.update(PerconaClusterHelper().parse_config())
    render(os.path.basename(config_file), config_file, context, perms=0o444)