diff --git a/application/controllers/migrate.php b/application/controllers/migrate.php new file mode 100644 index 00000000..97c2a7ef --- /dev/null +++ b/application/controllers/migrate.php @@ -0,0 +1,12 @@ +load->library('Migration'); + + if ( ! $this->migration->current()) { + show_error($this->migration->error_string()); + } + } + +} ?> diff --git a/system/language/english/migration_lang.php b/system/language/english/migration_lang.php new file mode 100644 index 00000000..fdf36ee9 --- /dev/null +++ b/system/language/english/migration_lang.php @@ -0,0 +1,13 @@ + $val) + { + $this->{'_' . $key} = $val; + } + + log_message('debug', 'Migrations class initialized'); + + // Are they trying to use migrations while it is disabled? + if ($this->_migration_enabled !== TRUE) + { + show_error('Migrations has been loaded but is disabled or set up incorrectly.'); + } + + // If not set, set it + $this->_migration_path == '' AND $this->_migration_path = APPPATH . 'migrations/'; + + // Add trailing slash if not set + $this->_migration_path = rtrim($this->_migration_path, '/').'/'; + + // Load migration language + $this->lang->load('migration'); + + // They'll probably be using dbforge + $this->load->dbforge(); + + // If the migrations table is missing, make it + if ( ! $this->db->table_exists('migrations')) + { + $this->dbforge->add_field(array( + 'version' => array('type' => 'INT', 'constraint' => 3), + )); + + $this->dbforge->create_table('migrations', TRUE); + + $this->db->insert('migrations', array('version' => 0)); + } + } + + // -------------------------------------------------------------------- + + /** + * Migrate to a schema version + * + * Calls each migration step required to get to the schema version of + * choice + * + * @param int Target schema version + * @return mixed TRUE if already latest, FALSE if failed, int if upgraded + */ + public function version($target_version) + { + $start = $current_version = $this->_get_version(); + $stop = $target_version; + + if ($target_version > $current_version) + { + // Moving Up + ++$start; + ++$stop; + $step = 1; + } + else + { + // Moving Down + $step = -1; + } + + $method = ($step === 1) ? 'up' : 'down'; + $migrations = array(); + + // We now prepare to actually DO the migrations + // But first let's make sure that everything is the way it should be + for ($i = $start; $i != $stop; $i += $step) + { + $f = glob(sprintf($this->_migration_path . '%03d_*.php', $i)); + + // Only one migration per step is permitted + if (count($f) > 1) + { + $this->_error_string = sprintf($this->lang->line('migration_multiple_version'), $i); + return FALSE; + } + + // Migration step not found + if (count($f) == 0) + { + // If trying to migrate up to a version greater than the last + // existing one, migrate to the last one. + if ($step == 1) + { + break; + } + + // If trying to migrate down but we're missing a step, + // something must definitely be wrong. + $this->_error_string = sprintf($this->lang->line('migration_not_found'), $i); + return FALSE; + } + + $file = basename($f[0]); + $name = basename($f[0], '.php'); + + // Filename validations + if (preg_match('/^\d{3}_(\w+)$/', $name, $match)) + { + $match[1] = strtolower($match[1]); + + // Cannot repeat a migration at different steps + if (in_array($match[1], $migrations)) + { + $this->_error_string = sprintf($this->lang->line('migration_multiple_version'), $match[1]); + return FALSE; + } + + include $f[0]; + $class = 'Migration_' . ucfirst($match[1]); + + if ( ! class_exists($class)) + { + $this->_error_string = sprintf($this->lang->line('migration_class_doesnt_exist'), $class); + return FALSE; + } + + if ( ! is_callable(array($class, $method))) + { + $this->_error_string = sprintf($this->lang->line('migration_missing_'.$method.'_method'), $class); + return FALSE; + } + + $migrations[] = $match[1]; + } + else + { + $this->_error_string = sprintf($this->lang->line('migration_invalid_filename'), $file); + return FALSE; + } + } + + log_message('debug', 'Current migration: ' . $current_version); + + $version = $i + ($step == 1 ? -1 : 0); + + // If there is nothing to do so quit + if ($migrations === array()) + { + return TRUE; + } + + log_message('debug', 'Migrating from ' . $method . ' to version ' . $version); + + // Loop through the migrations + foreach ($migrations AS $migration) + { + // Run the migration class + $class = 'Migration_' . ucfirst(strtolower($migration)); + call_user_func(array(new $class, $method)); + + $current_version += $step; + $this->_update_version($current_version); + } + + log_message('debug', 'Finished migrating to '.$current_version); + + return $current_version; + } + + // -------------------------------------------------------------------- + + /** + * Set's the schema to the latest migration + * + * @return mixed true if already latest, false if failed, int if upgraded + */ + public function latest() + { + if ( ! $migrations = $this->find_migrations()) + { + $this->_error_string = $this->line->lang('migration_none_found'); + return false; + } + + $last_migration = basename(end($migrations)); + + // Calculate the last migration step from existing migration + // filenames and procceed to the standard version migration + return $this->version((int) substr($last_migration, 0, 3)); + } + + // -------------------------------------------------------------------- + + /** + * Set's the schema to the migration version set in config + * + * @return mixed true if already current, false if failed, int if upgraded + */ + public function current() + { + return $this->version($this->_migration_version); + } + + // -------------------------------------------------------------------- + + /** + * Error string + * + * @return string Error message returned as a string + */ + public function error_string() + { + return $this->_error_string; + } + + // -------------------------------------------------------------------- + + /** + * Set's the schema to the latest migration + * + * @return mixed true if already latest, false if failed, int if upgraded + */ + protected function find_migrations() + { + // Load all *_*.php files in the migrations path + $files = glob($this->_migration_path . '*_*.php'); + $file_count = count($files); + + for ($i = 0; $i < $file_count; $i++) + { + // Mark wrongly formatted files as false for later filtering + $name = basename($files[$i], '.php'); + if ( ! preg_match('/^\d{3}_(\w+)$/', $name)) + { + $files[$i] = FALSE; + } + } + + sort($files); + return $files; + } + + // -------------------------------------------------------------------- + + /** + * Retrieves current schema version + * + * @return int Current Migration + */ + protected function _get_version() + { + $row = $this->db->get('migrations')->row(); + return $row ? $row->version : 0; + } + + // -------------------------------------------------------------------- + + /** + * Stores the current schema version + * + * @param int Migration reached + * @return bool + */ + protected function _update_version($migrations) + { + return $this->db->update('migrations', array( + 'version' => $migrations + )); + } + + // -------------------------------------------------------------------- + + /** + * Enable the use of CI super-global + * + * @param mixed $var + * @return mixed + */ + public function __get($var) + { + return get_instance()->$var; + } +} + +/* End of file Migration.php */ +/* Location: ./system/libraries/Migration.php */