Smooth Migration Plugin

The Smooth Migration plugin allows database migrations to continue running instead of aborting on failure. The rake db:migrate task will fail at the end of the migration instead of in the middle. This helps prevent getting stuck between migrations and needing to comment out code to continue migrating.

Requirements

• Rails >= 1.2

Installation

The traditional way:

  ruby script/plugin install http://smooth-migration.googlecode.com/svn/trunk/smooth_migration/

Or with piston:

  piston import http://smooth-migration.googlecode.com/svn/trunk/smooth_migration/ vendor/plugins/smooth_migration

Example

Before Smooth Migration

  == CreateSomeTable: migrating =================================================
  -- create_table(:users)
     -> 0.0039s
  -- add_column(:users, :email, :string)
     -> 0.0075s
  -- add_column(:table_does_not_exist, :foo, :string)
  rake aborted!
  SQLite3::SQLException: no such table: table_does_not_exist: ALTER TABLE table_does_not_exist ADD "foo" varchar(255)

  In this example, the migration created the users table, but then failed when attempting to
  add a column to a table that does not exist.  One problem is that your database is still on the
  previous schema version, so the next time you try to migrate, it will fail on creating the users table.

After Smooth Migration

  == CreateSomeTable: migrating =================================================
  -- create_table(:users)
     -> 0.0042s
  -- add_column(:users, :email, :string)
     -> 0.3769s
  -- add_column(:table_does_not_exist, :foo, :string)
     -> ActiveRecord::StatementInvalid
     -> SQLite3::SQLException: no such table: table_does_not_exist: ALTER TABLE table_does_not_exist ADD "foo" varchar(255)
  -- add_column(:users, :bar, :string)
     -> 0.0081s
  == CreateSomeTable: migrated (0.3910s) ========================================

  rake aborted!
  -- 1 Failures!  Review console output.

  The exception messages are displayed inline and the migration continues.  At the end of the migration
  an exception is through to abort the rake task and a failure notice is displayed.

Usage

Your migrations will become smooth after installing the plugin. If you want to migrate the old way, use:

  rake db:migrate SMOOTH=false

Or, in your environment configuration file:

  SmoothMigration.disabled = true

Copyright © 2007 Dan Manges, released under the MIT license.

Owner: Dan Manges

Home: http://code.google.com/p/smooth-migration/

Repository: http://smooth-migration.googlecode.com/svn/trunk/smooth_migration/

License: Rails' (MIT)

Category: Misc. Enhancements