45 lines
1.5 KiB
Plaintext
45 lines
1.5 KiB
Plaintext
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Description:
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The plugin migration generator assists in working with schema additions
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required by plugins. Instead of running migrations from plugins directly,
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the generator creates a regular Rails migration which will be responsible
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for migrating the plugins from their current version to the latest version
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installed.
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This is important because the set of application migrations remains an
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accurate record of the state of the database, even as plugins are installed
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and removed during the development process.
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Example:
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./script/generate plugin_migration [<plugin_name> <another_plugin_name> ...]
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This will generate:
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RAILS_ROOT
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|- db
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|-migrate
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|- xxx_plugin_migrations.rb
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which contains the migrations for the given plugin(s).
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Advanced Usage:
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There may be situations where you need *complete* control over the migrations
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of plugins in your application, migrating a certainly plugin down to X, and
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another plugin up to Y, where neither X or Y are the latest migrations for those
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plugins.
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For those unfortunate few, I have two pieces of advice:
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1. Why? This is a code smell [http://c2.com/xp/CodeSmell.html].
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2. Well, OK. Don't panic. You can completely control plugin migrations by
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creating your own migrations. To manually migrate a plugin to a specific
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version, simply use
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Engines.plugins[:your_plugin_name].migrate(version)
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where version is the integer of the migration this plugin should end
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up at.
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With great power comes great responsibility. Use this wisely.
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