migration lockfile lifetime

application/config/migration.php

@@ -37,5 +37,20 @@ $config['migration_version'] = 211;
 $config['migration_path'] = APPPATH . 'migrations/';
 
 
+/*
+|--------------------------------------------------------------------------
+| Migration Lockfile
+|--------------------------------------------------------------------------
+|
+| Path to the migration lockfile.
+| This lockfile prevents migrations from running twice
+|
+*/
+$config['migration_lockfile'] = sys_get_temp_dir() . '/.migration_running';
+
+// the maximum age of the lockfile in seconds
+$config['migration_lf_maxage'] = 30;
+
+
 /* End of file migration.php */
 /* Location: ./application/config/migration.php */

application/controllers/Migrate.php

@@ -3,6 +3,7 @@ class Migrate extends CI_Controller {
 
     public function index() {
         $this->load->library('Migration');
+        $this->load->config('migration');
 
         $result = array();
         $latest = $this->migration->latest();
@@ -12,7 +13,7 @@ class Migrate extends CI_Controller {
             log_message('error', 'Migration failed');
             $result['status'] = 'error';
         } else {
-            while (file_exists(APPPATH . 'cache/.migration_running')) {
+            while (file_exists($this->config->item('migration_lockfile'))) {
                 sleep(1);
             }
             $result['status'] = 'success';

system/libraries/Migration.php

@@ -91,7 +91,16 @@ class CI_Migration {
 	 * 
 	 * @var string
 	 */
-	protected $_migration_lockfile = APPPATH . 'cache/.migration_running';
+	protected $_migration_lockfile = NULL;
+
+	/**
+	 * Max Age of the migration lockfile
+	 * 
+	 * @var int
+	 */
+
+	protected $_migration_lf_maxage = NULL;
+
 
 	/**
 	 * Whether to automatically run migrations
@@ -147,6 +156,12 @@ class CI_Migration {
 		// Add trailing slash if not set
 		$this->_migration_path = rtrim($this->_migration_path, '/').'/';
 
+		// If not set, set it
+		$this->_migration_lockfile !== '' OR $this->_migration_lockfile = '/tmp/.migration_running';
+
+		// selockfile maxage if not set in config file. Fallback is 60 seconds. 
+		$this->_migration_lf_maxage !== '' OR $this->_migration_lf_maxage = 60;
+
 		// Load migration language
 		$this->lang->load('migration');
 
@@ -341,7 +356,27 @@ class CI_Migration {
 			}
 
 		} else {
-			log_message('debug', 'Migration process is currently locked. Second migration attempt ignored.');
+
+			log_message('debug', 'There is a lockfile for migrations. Checking the age...');
+
+			// Get the file creation date
+			$lockfile_ctime = filemtime($this->_migration_lockfile);
+
+			//compare to the current time
+			$tdiff = time() - $lockfile_ctime;
+			log_message('debug', 'Migration lockfile lifetime in seconds: '.$tdiff.'/'.$this->_migration_lf_maxage);
+
+			// if the file is older then the configured limit, delete it
+			if ($tdiff > $this->_migration_lf_maxage) {
+
+				unlink($this->_migration_lockfile);
+				log_message('debug', 'Deleted migration lockfile because it was older then maxage.');
+
+			} else {
+
+				log_message('debug', 'Migration process is currently locked. Second migration attempt ignored.');
+
+			}
 		}
 
 		return $current_version;