Give more helpful error messages when a migration fails

classes/minion/migration/exception.php

@@ -0,0 +1,33 @@
+<?php
+
+/**
+ * Minion exception, thrown during a migration error
+ */
+class Minion_Migration_Exception extends Kohana_Exception {
+
+	protected $_migration = array();
+
+	/**
+	 * Constructor
+	 *
+	 */
+	public function __construct($message, array $migration, array $variables = array(), $code = 0)
+	{
+		$variables[':migration-id']       = $migration['id'];
+		$variables[':migration-location'] = $migration['location'];
+
+		$this->_migration = $migration;
+
+		parent::__construct($message, $variables, $code);
+	}
+
+	/**
+	 * Get the migration that caused this exception to be thrown
+	 *
+	 * @return array
+	 */
+	public function get_migration()
+	{
+		return $this->_migration;
+	}
+}

classes/minion/migration/manager.php

@@ -182,7 +182,15 @@ class Minion_Migration_Manager {
 
 				$db = $this->_get_db_instance($instance->get_database_connection());
 
-				$instance->$method($db);
+				try 
+				{
+					$instance->$method($db);
+				}
+				catch(Database_Exception $e)
+				{
+					throw new Minion_Migration_Exception($e->getMessage(), $migration);
+				}
+
 
 				if($this->_dry_run)
 				{

classes/minion/task/db/migrate.php

@@ -89,10 +89,20 @@ class Minion_Task_Db_Migrate extends Minion_Task
 			// Sync the available migrations with those in the db
 			->sync_migration_files()
 
-			->set_dry_run($dry_run)
+			->set_dry_run($dry_run);
 
+		try
+		{
 			// Run migrations for specified locations & versions
-			->run_migration($locations, $targets, $this->_default_direction);
+			$manager->run_migration($locations, $targets, $this->_default_direction);
+		}
+		catch(Minion_Migration_Exception $e)
+		{
+			return View::factory('minion/task/db/migrate/exception')
+				->set('migration', $e->get_migration())
+				->set('error',     $e->getMessage());
+		}
+
 
 		$view = View::factory('minion/task/db/migrate')
 			->set('dry_run', $dry_run)

views/minion/task/db/migrate/exception.php

@@ -0,0 +1,3 @@
+Minion encountered an error while executing migration `<?php echo $migration['id']; ?>` (<?php echo $migration['description'] ?>):
+
+<?php echo $error; ?>