Hi, Alexey! On Dec 03, Alexey Botchkov wrote:

revision-id: 07f5d036fbb5bdcb011a84f5c882a062d9e609e7 (mariadb-10.4.0-54-g07f5d03) parent(s): 3afae13b548c903d86a55530d59fbf7d8666281f committer: Alexey Botchkov timestamp: 2018-12-03 02:35:52 +0400 message:

MDEV-5313 Improving merge audit api.

"improving audit api" ? we don't merge it anymore, right?

service_json and service_cfg_table interfaces added.

diff --git a/include/mysql/service_cfg_table.h b/include/mysql/service_cfg_table.h new file mode 100644 index 0000000..36660ff --- /dev/null +++ b/include/mysql/service_cfg_table.h @@ -0,0 +1,109 @@ +/* Copyright (C) 2018 MariaDB Corporation + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; version 2 of the License. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1301 USA */ + +#ifndef MYSQL_SERVICE_CFG_TABLE +#define MYSQL_SERVICE_CFG_TABLE + +/** + @file + cfg table service + + Reading plugin settings from the server table. + + This service lets the plugin to read it's settings + from the server table. + This 'cfg' table has two VARCHAR fields per row + which are + 'id' - the name of the setting + 'value' - the value of the respective 'id' setting + The structure 'cfg_table_row' reflects this format for + the data interchange with the service. + Fuctions of the service: + cfg_table_check_exists + checks if the table exists. + cfg_table_create - creates the table + parameers: + table_name - the name of the table + int id_len, int value_len - the length of the 'id' and 'value' + fields. + const struct cfg_table_row *defaults - table will be filled + with these default rows. + The list of rows is ended by {0,0} row + + cfg_table_set - replaces (inserts if not exists) the setting + parameters: + table_name - the name of the table + const char *id, const char *value - the 'id' and the new value + + cfg_table_get - reads the cft tale content + It return the number of rows in the table or -1 if error. + parameters: + table_name, + struct cfg_table_row *data_buf - buffer to store the records + int n_buf_row - the size of the buffer +*/

This is, of course, a very much overdue functionality. I'm not sure it should be limited to key/value pairs. On the other hand, if it's plugin config only, loaded once on startup - then it should be fine. Just need to make clear it's not for run-time data. In the implementation, make sure that when a table is opened, there are no other opened/locked tables. This will avoid deadlocks and prevent plugins from using it from inside another statement. Also, * I'd put the table name into pluginname namespace. Not quite sure how to do it, though. * Why do you need cfg_table_check_exists and cfg_table_create? A plugin only needs set and get methods. A table is automatically created on the first access, a plugin can always assume it exists. * may be even just one table, plugin_config? with two columns plugin_name and json_config? plugin gets the json on startup and that's all. No way for a plugin to access the table directly.

diff --git a/include/mysql/service_json.h b/include/mysql/service_json.h new file mode 100644 index 0000000..5d0e260 --- /dev/null +++ b/include/mysql/service_json.h ... +int js_type(const char *js, const char *js_end, + enum js_value_types *vt, + const char **v, int *vlen); +int js_get_array_item(const char *js, const char *js_end, int n_item, + enum js_value_types *vt, + const char **v, int *vlen); +int js_get_object_key(const char *js, const char *js_end, const char *key, + enum js_value_types *vt, + const char **v, int *vlen); +int js_get_object_nkey(const char *js,const char *js_end, int nkey, + const char **keyname, const char **keyname_end, + enum js_value_types *vt, + const char **v, int *vlen);

I wouldn't introduce ten different apis to access json. Just json_get(json, path) and json_set(json, path, value). Same path syntax everywhere, like on SQL level. Regards, Sergei Chief Architect MariaDB and security@mariadb.org