Plugin: BuyCourses: Bump to v7.5 to apply update on tax_perc in plugin_buycourses_services

Author: ywarnier

public/plugin/BuyCourses/CHANGELOG.md

@@ -1,3 +1,18 @@
+v7.5 - 2026-06-12
+====
+Fix: an empty tax rate on a service or a subscription can now be saved again, and is stored
+as NULL so the item falls back to the global tax rate (as intended). Older installations
+created the `tax_perc` column as NOT NULL on the services and subscription tables, which made
+saving an empty tax rate fail with "Column 'tax_perc' cannot be null".
+
+ACTION REQUIRED for installations updated from an earlier version: run the update procedure
+so these columns are made nullable. Either load [your-host]/plugin/BuyCourses/update.php in
+your browser as a platform administrator, or run this SQL manually:
+```sql
+ALTER TABLE plugin_buycourses_services MODIFY tax_perc int unsigned NULL;
+ALTER TABLE plugin_buycourses_subscription MODIFY tax_perc int unsigned NULL;
+```
+
 v7.4 - 2022-04-28
 ====
 Add subscriptions support.

public/plugin/BuyCourses/src/buy_course_plugin.class.php

@@ -117,7 +117,7 @@ class BuyCoursesPlugin extends Plugin
     public function __construct()
     {
         parent::__construct(
-            '7.1',
+            '7.5',
             '
                 Jose Angel Ruiz - NoSoloRed (original author) <br/>
                 Francis Gonzales and Yannick Warnier - BeezNest (integration) <br/>
@@ -363,6 +363,16 @@ public function update(): void
             if (!$res) {
                 echo Display::return_message($this->get_lang('ErrorUpdateFieldDB'), 'warning');
             }
+        } else {
+            // An empty tax rate must be stored as NULL so the service falls back to the
+            // global tax rate. Older installations created this column as NOT NULL.
+            $column = Database::fetch_assoc($res);
+            if (isset($column['Null']) && 'NO' === $column['Null']) {
+                $res = Database::query("ALTER TABLE $table MODIFY tax_perc int unsigned NULL");
+                if (!$res) {
+                    echo Display::return_message($this->get_lang('ErrorUpdateFieldDB'), 'warning');
+                }
+            }
         }
 
         $table = Database::get_main_table(self::TABLE_SALE);
@@ -576,6 +586,17 @@ public function update(): void
         )";
         Database::query($sql);
 
+        // An empty tax rate must be stored as NULL so the subscription falls back to the
+        // global tax rate. Older installations created this column as NOT NULL.
+        $res = Database::query("SHOW COLUMNS FROM $table WHERE Field = 'tax_perc'");
+        $column = Database::fetch_assoc($res);
+        if (isset($column['Null']) && 'NO' === $column['Null']) {
+            $res = Database::query("ALTER TABLE $table MODIFY tax_perc int unsigned NULL");
+            if (!$res) {
+                echo Display::return_message($this->get_lang('ErrorUpdateFieldDB'), 'warning');
+            }
+        }
+
         $table = Database::get_main_table(self::TABLE_SUBSCRIPTION_SALE);
         $sql = "CREATE TABLE IF NOT EXISTS $table (
             id int unsigned NOT NULL AUTO_INCREMENT,