Fail migrating schedule config when named timezones aren't loaded

doc/80-Upgrading.md

@@ -6,6 +6,13 @@ Usually the only manual steps involved are schema updates for the database.
 ## Upgrading to Version 1.0.0
 
 Icinga Reporting version 1.0.0 requires a schema update for the database.
+
+> **Note**
+>
+> In order for the migration script to be successful, you must [populate](https://dev.mysql.com/doc/refman/8.0/en/time-zone-support.html#time-zone-installation)
+> all the system named time zone information into your MSQL/MariaDB server. Otherwise, the migration will not succeed
+> and will produce an SQL error.
+
 If you're already using Icinga Web version `>= 2.12`, then you don't need to perform any of these steps manually.
 Icinga Web provides you the ability to perform such migrations in a simple way. You may be familiar with such an
 automation if you're an Icinga Director user. For those who are not using the latest version of Icinga Web, please

schema/mysql-upgrades/1.0.0.sql

@@ -2,6 +2,10 @@ DROP PROCEDURE IF EXISTS migrate_schedule_config;
 DELIMITER //
 CREATE PROCEDURE migrate_schedule_config()
 BEGIN
+  DECLARE session_time_zone text;
+  DECLARE session_time_zone_exists text;
+  DECLARE utc_time_zone text;
+
   DECLARE schedule_id int;
   DECLARE schedule_start bigint;
   DECLARE schedule_frequency enum('minutely', 'hourly', 'daily', 'weekly', 'monthly');
@@ -13,6 +17,15 @@ BEGIN
   DECLARE schedule CURSOR FOR SELECT id, start, frequency, config FROM schedule;
   DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = 1;
 
+  -- Determine the current session time zone name
+  SELECT IF(@@session.TIME_ZONE = 'SYSTEM', @@system_time_zone, @@session.TIME_ZONE) INTO session_time_zone;
+
+  SELECT Name INTO session_time_zone_exists FROM mysql.time_zone_name WHERE Name = session_time_zone LIMIT 1;
+  SELECT Name INTO utc_time_zone FROM mysql.time_zone_name WHERE Name = 'UTC' LIMIT 1;
+  IF utc_time_zone IS NULL OR session_time_zone_exists IS NULL THEN
+    SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = 'required named time zone information are not populated into mysql/mariadb';
+  END IF;
+
   OPEN schedule;
   read_loop: LOOP
     FETCH schedule INTO schedule_id, schedule_start, schedule_frequency, schedule_config;