Refactor migrations to handle postgresql specifically

Author: iMattPro

migrations/v20x/m15_language_iso.php …grations/v20x/m15_update_lang_schema.phpmigrations/v20x/m15_language_iso.php renamed to migrations/v20x/m15_update_lang_schema.php migrations/v20x/m15_language_iso.php renamed to migrations/v20x/m15_update_lang_schema.php

@@ -10,8 +10,18 @@
 
 namespace phpbb\boardrules\migrations\v20x;
 
-class m15_language_iso extends \phpbb\db\migration\container_aware_migration
+class m15_update_lang_schema extends \phpbb\db\migration\migration
 {
+	/**
+	 * @inheritDoc
+	 *
+	 * This migration is incompatible with PostgreSQL
+	 */
+	public function effectively_installed()
+	{
+		return $this->db->get_sql_layer() === 'postgres';
+	}
+
 	/**
 	 * @inheritDoc
 	 */
@@ -34,6 +44,11 @@ public function update_schema()
 					'rule_language' => array('VCHAR:30', ''),
 				),
 			),
+			'add_index' => array(
+				$this->table_prefix . 'boardrules' => array(
+					'rule_language' => array('rule_language'),
+				),
+			),
 		);
 	}
 
@@ -43,9 +58,9 @@ public function update_schema()
 	public function revert_schema()
 	{
 		return array(
-			'change_columns' => array(
+			'drop_keys' => array(
 				$this->table_prefix . 'boardrules' => array(
-					'rule_language' => array('UINT', ''),
+					'rule_language',
 				),
 			),
 		);

migrations/v20x/m16_update_lang_postgres.php

@@ -0,0 +1,116 @@
+<?php
+/**
+ *
+ * Board Rules extension for the phpBB Forum Software package.
+ *
+ * @copyright (c) 2017 phpBB Limited <https://www.phpbb.com>
+ * @license GNU General Public License, version 2 (GPL-2.0)
+ *
+ */
+
+namespace phpbb\boardrules\migrations\v20x;
+
+class m16_update_lang_postgres extends \phpbb\db\migration\migration
+{
+	/**
+	 * @inheritDoc
+	 *
+	 * This migration is only for PostgreSQL
+	 */
+	public function effectively_installed()
+	{
+		return strpos($this->db->get_sql_layer(), 'postgres') === false;
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	static public function depends_on()
+	{
+		return array(
+			'\phpbb\boardrules\migrations\v10x\m7_sample_rule_data',
+			'\phpbb\boardrules\migrations\v20x\m14_reparse',
+			'\phpbb\boardrules\migrations\v20x\m15_update_lang_schema',
+		);
+	}
+
+	/**
+	 * @inheritDoc
+	 */
+	public function update_data()
+	{
+		return array(
+			array('custom', array(array($this, 'alter_rule_language'))),
+		);
+	}
+
+	/**
+	 * Alter rule_language column for PostgreSQL
+	 *
+	 * PostgreSQL does not allow us to change a column's data type if it
+	 * already contains values, so the normal 'change_columns' action fails.
+	 * To work around this, we re-create a new rule_language column with
+	 * the new data type and copy the new data to it via specific queries.
+	 *
+	 * @throws \RuntimeException
+	 */
+	public function alter_rule_language()
+	{
+		// Ensure we are only processing this on postgresql dbms
+		if (strpos($this->db->get_sql_layer(), 'postgres') === false)
+		{
+			return;
+		}
+
+		$boardrules_table = $this->table_prefix . 'boardrules';
+
+		// Rename existing column to a temporary name
+		$sql = 'ALTER TABLE ' . $boardrules_table . ' 
+			RENAME COLUMN rule_language TO old_rule_language';
+		$this->db->sql_query($sql);
+
+		// Stop running if column rename failed (custom language must be hardcoded)
+		if (!$this->db_tools->sql_column_exists($boardrules_table , 'old_rule_language'))
+		{
+			throw new \RuntimeException('The column ‘rule_language’ could not be renamed.');
+		}
+
+		// Add a new rule_language column
+		$this->db_tools->sql_column_add($boardrules_table, 'rule_language', array('VCHAR:30', ''));
+
+		// Stop running if add column failed (custom language must be hardcoded)
+		if (!$this->db_tools->sql_column_exists($boardrules_table, 'rule_language'))
+		{
+			throw new \RuntimeException('The column ‘rule_language’ could not be created.');
+		}
+
+		// Add an index for the rule_language column
+		$this->db_tools->sql_create_index($boardrules_table, 'rule_language', 'rule_language');
+
+		// Get installed language identifiers and iso codes
+		$sql = 'SELECT lang_id, lang_iso
+			FROM ' . LANG_TABLE;
+		$result = $this->db->sql_query($sql);
+		$rows = $this->db->sql_fetchrowset($result);
+		$this->db->sql_freeresult($result);
+
+		// Update the languages in the boardrules table, from id to iso
+		if (!empty($rows))
+		{
+			$this->db->sql_transaction('begin');
+
+			foreach ($rows as $row)
+			{
+				$sql = 'UPDATE ' . $boardrules_table . "
+					SET rule_language = '" . $this->db->sql_escape($row['lang_iso']) . "'
+					WHERE old_rule_language = " . (int) $row['lang_id'];
+				$this->db->sql_query($sql);
+			}
+
+			$this->db->sql_transaction('commit');
+		}
+
+		// Drop the temporary column
+		$this->db_tools->sql_column_remove($boardrules_table, 'old_rule_language');
+	}
+}