1 files changed, 235 insertions, 0 deletions
diff --git a/phpBB/phpbb/db/migration/schema_generator.php b/phpBB/phpbb/db/migration/schema_generator.php
new file mode 100644
index 0000000000..91d8307d91
--- /dev/null
+++ b/phpBB/phpbb/db/migration/schema_generator.php
@@ -0,0 +1,235 @@
+<?php
+/**
+*
+* This file is part of the phpBB Forum Software package.
+*
+* @copyright (c) phpBB Limited <https://www.phpbb.com>
+* @license GNU General Public License, version 2 (GPL-2.0)
+*
+* For full copyright and license information, please see
+* the docs/CREDITS.txt file.
+*
+*/
+
+namespace phpbb\db\migration;
+
+/**
+* The schema generator generates the schema based on the existing migrations
+*/
+class schema_generator
+{
+	/** @var \phpbb\config\config */
+	protected $config;
+
+	/** @var \phpbb\db\driver\driver_interface */
+	protected $db;
+
+	/** @var \phpbb\db\tools */
+	protected $db_tools;
+
+	/** @var array */
+	protected $class_names;
+
+	/** @var string */
+	protected $table_prefix;
+
+	/** @var string */
+	protected $phpbb_root_path;
+
+	/** @var string */
+	protected $php_ext;
+
+	/** @var array */
+	protected $tables;
+
+	/** @var array */
+	protected $dependencies = array();
+
+	/**
+	* Constructor
+	*/
+	public function __construct(array $class_names, \phpbb\config\config $config, \phpbb\db\driver\driver_interface $db, \phpbb\db\tools $db_tools, $phpbb_root_path, $php_ext, $table_prefix)
+	{
+		$this->config = $config;
+		$this->db = $db;
+		$this->db_tools = $db_tools;
+		$this->class_names = $class_names;
+		$this->phpbb_root_path = $phpbb_root_path;
+		$this->php_ext = $php_ext;
+		$this->table_prefix = $table_prefix;
+	}
+
+	/**
+	* Loads all migrations and their application state from the database.
+	*
+	* @return array
+	*/
+	public function get_schema()
+	{
+		if (!empty($this->tables))
+		{
+			return $this->tables;
+		}
+
+		$migrations = $this->class_names;
+
+		$tree = array();
+		$check_dependencies = true;
+		while (!empty($migrations))
+		{
+			foreach ($migrations as $migration_class)
+			{
+				$open_dependencies = array_diff($migration_class::depends_on(), $tree);
+
+				if (empty($open_dependencies))
+				{
+					$migration = new $migration_class($this->config, $this->db, $this->db_tools, $this->phpbb_root_path, $this->php_ext, $this->table_prefix);
+					$tree[] = $migration_class;
+					$migration_key = array_search($migration_class, $migrations);
+
+					foreach ($migration->update_schema() as $change_type => $data)
+					{
+						if ($change_type === 'add_tables')
+						{
+							foreach ($data as $table => $table_data)
+							{
+								$this->tables[$table] = $table_data;
+							}
+						}
+						else if ($change_type === 'drop_tables')
+						{
+							foreach ($data as $table)
+							{
+								unset($this->tables[$table]);
+							}
+						}
+						else if ($change_type === 'add_columns')
+						{
+							foreach ($data as $table => $add_columns)
+							{
+								foreach ($add_columns as $column => $column_data)
+								{
+									if (isset($column_data['after']))
+									{
+										$columns = $this->tables[$table]['COLUMNS'];
+										$offset = array_search($column_data['after'], array_keys($columns));
+										unset($column_data['after']);
+
+										if ($offset === false)
+										{
+											$this->tables[$table]['COLUMNS'][$column] = array_values($column_data);
+										}
+										else
+										{
+											$this->tables[$table]['COLUMNS'] = array_merge(array_slice($columns, 0, $offset + 1, true), array($column => array_values($column_data)), array_slice($columns, $offset));
+										}
+									}
+									else
+									{
+										$this->tables[$table]['COLUMNS'][$column] = $column_data;
+									}
+								}
+							}
+						}
+						else if ($change_type === 'change_columns')
+						{
+							foreach ($data as $table => $change_columns)
+							{
+								foreach ($change_columns as $column => $column_data)
+								{
+									$this->tables[$table]['COLUMNS'][$column] = $column_data;
+								}
+							}
+						}
+						else if ($change_type === 'drop_columns')
+						{
+							foreach ($data as $table => $drop_columns)
+							{
+								if (is_array($drop_columns))
+								{
+									foreach ($drop_columns as $column)
+									{
+										unset($this->tables[$table]['COLUMNS'][$column]);
+									}
+								}
+								else
+								{
+									unset($this->tables[$table]['COLUMNS'][$drop_columns]);
+								}
+							}
+						}
+						else if ($change_type === 'add_unique_index')
+						{
+							foreach ($data as $table => $add_index)
+							{
+								foreach ($add_index as $key => $index_data)
+								{
+									$this->tables[$table]['KEYS'][$key] = array('UNIQUE', $index_data);
+								}
+							}
+						}
+						else if ($change_type === 'add_index')
+						{
+							foreach ($data as $table => $add_index)
+							{
+								foreach ($add_index as $key => $index_data)
+								{
+									$this->tables[$table]['KEYS'][$key] = array('INDEX', $index_data);
+								}
+							}
+						}
+						else if ($change_type === 'drop_keys')
+						{
+							foreach ($data as $table => $drop_keys)
+							{
+								foreach ($drop_keys as $key)
+								{
+									unset($this->tables[$table]['KEYS'][$key]);
+								}
+							}
+						}
+						else
+						{
+							var_dump($change_type);
+						}
+					}
+					unset($migrations[$migration_key]);
+				}
+				else if ($check_dependencies)
+				{
+					$this->dependencies = array_merge($this->dependencies, $open_dependencies);
+				}
+			}
+
+			// Only run this check after the first run
+			if ($check_dependencies)
+			{
+				$this->check_dependencies();
+				$check_dependencies = false;
+			}
+		}
+
+		ksort($this->tables);
+		return $this->tables;
+	}
+
+	/**
+	* Check if one of the migrations files' dependencies can't be resolved
+	* by the supplied list of migrations
+	*
+	* @throws \UnexpectedValueException If a dependency can't be resolved
+	*/
+	protected function check_dependencies()
+	{
+		// Strip duplicate values from array
+		$this->dependencies = array_unique($this->dependencies);
+
+		foreach ($this->dependencies as $dependency)
+		{
+			if (!in_array($dependency, $this->class_names))
+			{
+				throw new \UnexpectedValueException("Unable to resolve the dependency '$dependency'");
+			}
+		}
+	}
+}