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cd130297ec
Previously we weren't passing in the spec_name, so this wasn't able to pick up the alternate schema names when using multiple databases.
1394 lines
45 KiB
Ruby
1394 lines
45 KiB
Ruby
# frozen_string_literal: true
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require "benchmark"
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require "set"
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require "zlib"
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require "active_support/core_ext/module/attribute_accessors"
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require "active_support/actionable_error"
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module ActiveRecord
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class MigrationError < ActiveRecordError #:nodoc:
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def initialize(message = nil)
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message = "\n\n#{message}\n\n" if message
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super
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end
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end
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# Exception that can be raised to stop migrations from being rolled back.
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# For example the following migration is not reversible.
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# Rolling back this migration will raise an ActiveRecord::IrreversibleMigration error.
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#
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# class IrreversibleMigrationExample < ActiveRecord::Migration[5.0]
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# def change
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# create_table :distributors do |t|
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# t.string :zipcode
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# end
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#
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# execute <<~SQL
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# ALTER TABLE distributors
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# ADD CONSTRAINT zipchk
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# CHECK (char_length(zipcode) = 5) NO INHERIT;
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# SQL
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# end
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# end
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#
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# There are two ways to mitigate this problem.
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#
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# 1. Define <tt>#up</tt> and <tt>#down</tt> methods instead of <tt>#change</tt>:
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#
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# class ReversibleMigrationExample < ActiveRecord::Migration[5.0]
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# def up
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# create_table :distributors do |t|
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# t.string :zipcode
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# end
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#
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# execute <<~SQL
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# ALTER TABLE distributors
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# ADD CONSTRAINT zipchk
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# CHECK (char_length(zipcode) = 5) NO INHERIT;
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# SQL
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# end
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#
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# def down
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# execute <<~SQL
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# ALTER TABLE distributors
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# DROP CONSTRAINT zipchk
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# SQL
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#
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# drop_table :distributors
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# end
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# end
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#
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# 2. Use the #reversible method in <tt>#change</tt> method:
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#
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# class ReversibleMigrationExample < ActiveRecord::Migration[5.0]
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# def change
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# create_table :distributors do |t|
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# t.string :zipcode
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# end
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#
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# reversible do |dir|
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# dir.up do
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# execute <<~SQL
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# ALTER TABLE distributors
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# ADD CONSTRAINT zipchk
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# CHECK (char_length(zipcode) = 5) NO INHERIT;
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# SQL
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# end
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#
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# dir.down do
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# execute <<~SQL
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# ALTER TABLE distributors
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# DROP CONSTRAINT zipchk
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# SQL
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# end
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# end
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# end
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# end
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class IrreversibleMigration < MigrationError
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end
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class DuplicateMigrationVersionError < MigrationError #:nodoc:
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def initialize(version = nil)
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if version
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super("Multiple migrations have the version number #{version}.")
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else
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super("Duplicate migration version error.")
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end
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end
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end
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class DuplicateMigrationNameError < MigrationError #:nodoc:
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def initialize(name = nil)
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if name
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super("Multiple migrations have the name #{name}.")
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else
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super("Duplicate migration name.")
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end
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end
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end
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class UnknownMigrationVersionError < MigrationError #:nodoc:
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def initialize(version = nil)
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if version
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super("No migration with version number #{version}.")
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else
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super("Unknown migration version.")
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end
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end
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end
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class IllegalMigrationNameError < MigrationError #:nodoc:
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def initialize(name = nil)
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if name
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super("Illegal name for migration file: #{name}\n\t(only lower case letters, numbers, and '_' allowed).")
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else
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super("Illegal name for migration.")
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end
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end
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end
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class PendingMigrationError < MigrationError #:nodoc:
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include ActiveSupport::ActionableError
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action "Run pending migrations" do
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ActiveRecord::Tasks::DatabaseTasks.migrate
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end
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def initialize(message = nil)
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if !message && defined?(Rails.env)
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super("Migrations are pending. To resolve this issue, run:\n\n rails db:migrate RAILS_ENV=#{::Rails.env}")
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elsif !message
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super("Migrations are pending. To resolve this issue, run:\n\n rails db:migrate")
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else
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super
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end
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end
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end
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class ConcurrentMigrationError < MigrationError #:nodoc:
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DEFAULT_MESSAGE = "Cannot run migrations because another migration process is currently running."
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RELEASE_LOCK_FAILED_MESSAGE = "Failed to release advisory lock"
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def initialize(message = DEFAULT_MESSAGE)
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super
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end
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end
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class NoEnvironmentInSchemaError < MigrationError #:nodoc:
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def initialize
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msg = "Environment data not found in the schema. To resolve this issue, run: \n\n rails db:environment:set"
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if defined?(Rails.env)
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super("#{msg} RAILS_ENV=#{::Rails.env}")
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else
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super(msg)
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end
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end
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end
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class ProtectedEnvironmentError < ActiveRecordError #:nodoc:
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def initialize(env = "production")
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msg = +"You are attempting to run a destructive action against your '#{env}' database.\n"
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msg << "If you are sure you want to continue, run the same command with the environment variable:\n"
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msg << "DISABLE_DATABASE_ENVIRONMENT_CHECK=1"
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super(msg)
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end
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end
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class EnvironmentMismatchError < ActiveRecordError
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def initialize(current: nil, stored: nil)
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msg = +"You are attempting to modify a database that was last run in `#{ stored }` environment.\n"
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msg << "You are running in `#{ current }` environment. "
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msg << "If you are sure you want to continue, first set the environment using:\n\n"
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msg << " rails db:environment:set"
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if defined?(Rails.env)
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super("#{msg} RAILS_ENV=#{::Rails.env}\n\n")
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else
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super("#{msg}\n\n")
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end
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end
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end
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# = Active Record Migrations
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#
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# Migrations can manage the evolution of a schema used by several physical
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# databases. It's a solution to the common problem of adding a field to make
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# a new feature work in your local database, but being unsure of how to
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# push that change to other developers and to the production server. With
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# migrations, you can describe the transformations in self-contained classes
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# that can be checked into version control systems and executed against
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# another database that might be one, two, or five versions behind.
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#
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# Example of a simple migration:
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#
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# class AddSsl < ActiveRecord::Migration[5.0]
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# def up
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# add_column :accounts, :ssl_enabled, :boolean, default: true
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# end
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#
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# def down
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# remove_column :accounts, :ssl_enabled
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# end
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# end
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#
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# This migration will add a boolean flag to the accounts table and remove it
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# if you're backing out of the migration. It shows how all migrations have
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# two methods +up+ and +down+ that describes the transformations
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# required to implement or remove the migration. These methods can consist
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# of both the migration specific methods like +add_column+ and +remove_column+,
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# but may also contain regular Ruby code for generating data needed for the
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# transformations.
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#
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# Example of a more complex migration that also needs to initialize data:
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#
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# class AddSystemSettings < ActiveRecord::Migration[5.0]
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# def up
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# create_table :system_settings do |t|
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# t.string :name
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# t.string :label
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# t.text :value
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# t.string :type
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# t.integer :position
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# end
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#
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# SystemSetting.create name: 'notice',
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# label: 'Use notice?',
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# value: 1
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# end
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#
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# def down
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# drop_table :system_settings
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# end
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# end
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#
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# This migration first adds the +system_settings+ table, then creates the very
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# first row in it using the Active Record model that relies on the table. It
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# also uses the more advanced +create_table+ syntax where you can specify a
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# complete table schema in one block call.
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#
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# == Available transformations
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#
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# === Creation
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#
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# * <tt>create_join_table(table_1, table_2, options)</tt>: Creates a join
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# table having its name as the lexical order of the first two
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# arguments. See
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# ActiveRecord::ConnectionAdapters::SchemaStatements#create_join_table for
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# details.
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# * <tt>create_table(name, options)</tt>: Creates a table called +name+ and
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# makes the table object available to a block that can then add columns to it,
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# following the same format as +add_column+. See example above. The options hash
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# is for fragments like "DEFAULT CHARSET=UTF-8" that are appended to the create
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# table definition.
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# * <tt>add_column(table_name, column_name, type, options)</tt>: Adds a new column
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# to the table called +table_name+
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# named +column_name+ specified to be one of the following types:
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# <tt>:string</tt>, <tt>:text</tt>, <tt>:integer</tt>, <tt>:float</tt>,
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# <tt>:decimal</tt>, <tt>:datetime</tt>, <tt>:timestamp</tt>, <tt>:time</tt>,
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# <tt>:date</tt>, <tt>:binary</tt>, <tt>:boolean</tt>. A default value can be
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# specified by passing an +options+ hash like <tt>{ default: 11 }</tt>.
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# Other options include <tt>:limit</tt> and <tt>:null</tt> (e.g.
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# <tt>{ limit: 50, null: false }</tt>) -- see
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# ActiveRecord::ConnectionAdapters::TableDefinition#column for details.
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# * <tt>add_foreign_key(from_table, to_table, options)</tt>: Adds a new
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# foreign key. +from_table+ is the table with the key column, +to_table+ contains
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# the referenced primary key.
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# * <tt>add_index(table_name, column_names, options)</tt>: Adds a new index
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# with the name of the column. Other options include
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# <tt>:name</tt>, <tt>:unique</tt> (e.g.
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# <tt>{ name: 'users_name_index', unique: true }</tt>) and <tt>:order</tt>
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# (e.g. <tt>{ order: { name: :desc } }</tt>).
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# * <tt>add_reference(:table_name, :reference_name)</tt>: Adds a new column
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# +reference_name_id+ by default an integer. See
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# ActiveRecord::ConnectionAdapters::SchemaStatements#add_reference for details.
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# * <tt>add_timestamps(table_name, options)</tt>: Adds timestamps (+created_at+
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# and +updated_at+) columns to +table_name+.
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#
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# === Modification
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#
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# * <tt>change_column(table_name, column_name, type, options)</tt>: Changes
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# the column to a different type using the same parameters as add_column.
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# * <tt>change_column_default(table_name, column_name, default_or_changes)</tt>:
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# Sets a default value for +column_name+ defined by +default_or_changes+ on
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# +table_name+. Passing a hash containing <tt>:from</tt> and <tt>:to</tt>
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# as +default_or_changes+ will make this change reversible in the migration.
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# * <tt>change_column_null(table_name, column_name, null, default = nil)</tt>:
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# Sets or removes a +NOT NULL+ constraint on +column_name+. The +null+ flag
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# indicates whether the value can be +NULL+. See
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# ActiveRecord::ConnectionAdapters::SchemaStatements#change_column_null for
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# details.
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# * <tt>change_table(name, options)</tt>: Allows to make column alterations to
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# the table called +name+. It makes the table object available to a block that
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# can then add/remove columns, indexes or foreign keys to it.
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# * <tt>rename_column(table_name, column_name, new_column_name)</tt>: Renames
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# a column but keeps the type and content.
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# * <tt>rename_index(table_name, old_name, new_name)</tt>: Renames an index.
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# * <tt>rename_table(old_name, new_name)</tt>: Renames the table called +old_name+
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# to +new_name+.
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#
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# === Deletion
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#
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# * <tt>drop_table(name)</tt>: Drops the table called +name+.
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# * <tt>drop_join_table(table_1, table_2, options)</tt>: Drops the join table
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# specified by the given arguments.
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# * <tt>remove_column(table_name, column_name, type, options)</tt>: Removes the column
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# named +column_name+ from the table called +table_name+.
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# * <tt>remove_columns(table_name, *column_names)</tt>: Removes the given
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# columns from the table definition.
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# * <tt>remove_foreign_key(from_table, to_table = nil, **options)</tt>: Removes the
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# given foreign key from the table called +table_name+.
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# * <tt>remove_index(table_name, column: column_names)</tt>: Removes the index
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# specified by +column_names+.
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# * <tt>remove_index(table_name, name: index_name)</tt>: Removes the index
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# specified by +index_name+.
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# * <tt>remove_reference(table_name, ref_name, options)</tt>: Removes the
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# reference(s) on +table_name+ specified by +ref_name+.
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# * <tt>remove_timestamps(table_name, options)</tt>: Removes the timestamp
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# columns (+created_at+ and +updated_at+) from the table definition.
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#
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# == Irreversible transformations
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#
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# Some transformations are destructive in a manner that cannot be reversed.
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# Migrations of that kind should raise an <tt>ActiveRecord::IrreversibleMigration</tt>
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# exception in their +down+ method.
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#
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# == Running migrations from within Rails
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#
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# The Rails package has several tools to help create and apply migrations.
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#
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# To generate a new migration, you can use
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# rails generate migration MyNewMigration
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#
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# where MyNewMigration is the name of your migration. The generator will
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# create an empty migration file <tt>timestamp_my_new_migration.rb</tt>
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# in the <tt>db/migrate/</tt> directory where <tt>timestamp</tt> is the
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# UTC formatted date and time that the migration was generated.
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#
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# There is a special syntactic shortcut to generate migrations that add fields to a table.
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#
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# rails generate migration add_fieldname_to_tablename fieldname:string
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#
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# This will generate the file <tt>timestamp_add_fieldname_to_tablename.rb</tt>, which will look like this:
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# class AddFieldnameToTablename < ActiveRecord::Migration[5.0]
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# def change
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# add_column :tablenames, :fieldname, :string
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# end
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# end
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#
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# To run migrations against the currently configured database, use
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# <tt>rails db:migrate</tt>. This will update the database by running all of the
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# pending migrations, creating the <tt>schema_migrations</tt> table
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# (see "About the schema_migrations table" section below) if missing. It will also
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# invoke the db:schema:dump command, which will update your db/schema.rb file
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# to match the structure of your database.
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#
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# To roll the database back to a previous migration version, use
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# <tt>rails db:rollback VERSION=X</tt> where <tt>X</tt> is the version to which
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# you wish to downgrade. Alternatively, you can also use the STEP option if you
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# wish to rollback last few migrations. <tt>rails db:rollback STEP=2</tt> will rollback
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# the latest two migrations.
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#
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# If any of the migrations throw an <tt>ActiveRecord::IrreversibleMigration</tt> exception,
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# that step will fail and you'll have some manual work to do.
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#
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# == Database support
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#
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# Migrations are currently supported in MySQL, PostgreSQL, SQLite,
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# SQL Server, and Oracle (all supported databases except DB2).
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#
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# == More examples
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#
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# Not all migrations change the schema. Some just fix the data:
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#
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# class RemoveEmptyTags < ActiveRecord::Migration[5.0]
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# def up
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# Tag.all.each { |tag| tag.destroy if tag.pages.empty? }
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# end
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#
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# def down
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# # not much we can do to restore deleted data
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# raise ActiveRecord::IrreversibleMigration, "Can't recover the deleted tags"
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# end
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# end
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#
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# Others remove columns when they migrate up instead of down:
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#
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# class RemoveUnnecessaryItemAttributes < ActiveRecord::Migration[5.0]
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# def up
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# remove_column :items, :incomplete_items_count
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# remove_column :items, :completed_items_count
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# end
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#
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# def down
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# add_column :items, :incomplete_items_count
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# add_column :items, :completed_items_count
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# end
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# end
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#
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# And sometimes you need to do something in SQL not abstracted directly by migrations:
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#
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# class MakeJoinUnique < ActiveRecord::Migration[5.0]
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# def up
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# execute "ALTER TABLE `pages_linked_pages` ADD UNIQUE `page_id_linked_page_id` (`page_id`,`linked_page_id`)"
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# end
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#
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# def down
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# execute "ALTER TABLE `pages_linked_pages` DROP INDEX `page_id_linked_page_id`"
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# end
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# end
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#
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# == Using a model after changing its table
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#
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# Sometimes you'll want to add a column in a migration and populate it
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# immediately after. In that case, you'll need to make a call to
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# <tt>Base#reset_column_information</tt> in order to ensure that the model has the
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# latest column data from after the new column was added. Example:
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#
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# class AddPeopleSalary < ActiveRecord::Migration[5.0]
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# def up
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# add_column :people, :salary, :integer
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# Person.reset_column_information
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# Person.all.each do |p|
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# p.update_attribute :salary, SalaryCalculator.compute(p)
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# end
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# end
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# end
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#
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# == Controlling verbosity
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#
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# By default, migrations will describe the actions they are taking, writing
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# them to the console as they happen, along with benchmarks describing how
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# long each step took.
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#
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# You can quiet them down by setting ActiveRecord::Migration.verbose = false.
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#
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# You can also insert your own messages and benchmarks by using the +say_with_time+
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# method:
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#
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# def up
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# ...
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# say_with_time "Updating salaries..." do
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# Person.all.each do |p|
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# p.update_attribute :salary, SalaryCalculator.compute(p)
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# end
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# end
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# ...
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# end
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#
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# The phrase "Updating salaries..." would then be printed, along with the
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# benchmark for the block when the block completes.
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#
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# == Timestamped Migrations
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#
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# By default, Rails generates migrations that look like:
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#
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# 20080717013526_your_migration_name.rb
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#
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# The prefix is a generation timestamp (in UTC).
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#
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# If you'd prefer to use numeric prefixes, you can turn timestamped migrations
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# off by setting:
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#
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|
# config.active_record.timestamped_migrations = false
|
|
#
|
|
# In application.rb.
|
|
#
|
|
# == Reversible Migrations
|
|
#
|
|
# Reversible migrations are migrations that know how to go +down+ for you.
|
|
# You simply supply the +up+ logic, and the Migration system figures out
|
|
# how to execute the down commands for you.
|
|
#
|
|
# To define a reversible migration, define the +change+ method in your
|
|
# migration like this:
|
|
#
|
|
# class TenderloveMigration < ActiveRecord::Migration[5.0]
|
|
# def change
|
|
# create_table(:horses) do |t|
|
|
# t.column :content, :text
|
|
# t.column :remind_at, :datetime
|
|
# end
|
|
# end
|
|
# end
|
|
#
|
|
# This migration will create the horses table for you on the way up, and
|
|
# automatically figure out how to drop the table on the way down.
|
|
#
|
|
# Some commands cannot be reversed. If you care to define how to move up
|
|
# and down in these cases, you should define the +up+ and +down+ methods
|
|
# as before.
|
|
#
|
|
# If a command cannot be reversed, an
|
|
# <tt>ActiveRecord::IrreversibleMigration</tt> exception will be raised when
|
|
# the migration is moving down.
|
|
#
|
|
# For a list of commands that are reversible, please see
|
|
# <tt>ActiveRecord::Migration::CommandRecorder</tt>.
|
|
#
|
|
# == Transactional Migrations
|
|
#
|
|
# If the database adapter supports DDL transactions, all migrations will
|
|
# automatically be wrapped in a transaction. There are queries that you
|
|
# can't execute inside a transaction though, and for these situations
|
|
# you can turn the automatic transactions off.
|
|
#
|
|
# class ChangeEnum < ActiveRecord::Migration[5.0]
|
|
# disable_ddl_transaction!
|
|
#
|
|
# def up
|
|
# execute "ALTER TYPE model_size ADD VALUE 'new_value'"
|
|
# end
|
|
# end
|
|
#
|
|
# Remember that you can still open your own transactions, even if you
|
|
# are in a Migration with <tt>self.disable_ddl_transaction!</tt>.
|
|
class Migration
|
|
autoload :CommandRecorder, "active_record/migration/command_recorder"
|
|
autoload :Compatibility, "active_record/migration/compatibility"
|
|
|
|
# This must be defined before the inherited hook, below
|
|
class Current < Migration #:nodoc:
|
|
end
|
|
|
|
def self.inherited(subclass) #:nodoc:
|
|
super
|
|
if subclass.superclass == Migration
|
|
raise StandardError, "Directly inheriting from ActiveRecord::Migration is not supported. " \
|
|
"Please specify the Rails release the migration was written for:\n" \
|
|
"\n" \
|
|
" class #{subclass} < ActiveRecord::Migration[4.2]"
|
|
end
|
|
end
|
|
|
|
def self.[](version)
|
|
Compatibility.find(version)
|
|
end
|
|
|
|
def self.current_version
|
|
ActiveRecord::VERSION::STRING.to_f
|
|
end
|
|
|
|
MigrationFilenameRegexp = /\A([0-9]+)_([_a-z0-9]*)\.?([_a-z0-9]*)?\.rb\z/ #:nodoc:
|
|
|
|
# This class is used to verify that all migrations have been run before
|
|
# loading a web page if <tt>config.active_record.migration_error</tt> is set to :page_load
|
|
class CheckPending
|
|
def initialize(app)
|
|
@app = app
|
|
@last_check = 0
|
|
end
|
|
|
|
def call(env)
|
|
mtime = ActiveRecord::Base.connection.migration_context.last_migration.mtime.to_i
|
|
if @last_check < mtime
|
|
ActiveRecord::Migration.check_pending!(connection)
|
|
@last_check = mtime
|
|
end
|
|
@app.call(env)
|
|
end
|
|
|
|
private
|
|
def connection
|
|
ActiveRecord::Base.connection
|
|
end
|
|
end
|
|
|
|
class << self
|
|
attr_accessor :delegate #:nodoc:
|
|
attr_accessor :disable_ddl_transaction #:nodoc:
|
|
|
|
def nearest_delegate #:nodoc:
|
|
delegate || superclass.nearest_delegate
|
|
end
|
|
|
|
# Raises <tt>ActiveRecord::PendingMigrationError</tt> error if any migrations are pending.
|
|
def check_pending!(connection = Base.connection)
|
|
raise ActiveRecord::PendingMigrationError if connection.migration_context.needs_migration?
|
|
end
|
|
|
|
def load_schema_if_pending!
|
|
current_config = Base.connection_config
|
|
all_configs = ActiveRecord::Base.configurations.configs_for(env_name: Rails.env)
|
|
|
|
needs_update = !all_configs.all? do |db_config|
|
|
Tasks::DatabaseTasks.schema_up_to_date?(db_config.config, ActiveRecord::Base.schema_format, nil, Rails.env, db_config.spec_name)
|
|
end
|
|
|
|
if needs_update
|
|
# Roundtrip to Rake to allow plugins to hook into database initialization.
|
|
root = defined?(ENGINE_ROOT) ? ENGINE_ROOT : Rails.root
|
|
FileUtils.cd(root) do
|
|
Base.clear_all_connections!
|
|
system("bin/rails db:test:prepare")
|
|
end
|
|
end
|
|
|
|
# Establish a new connection, the old database may be gone (db:test:prepare uses purge)
|
|
Base.establish_connection(current_config)
|
|
|
|
check_pending!
|
|
end
|
|
|
|
def maintain_test_schema! #:nodoc:
|
|
if ActiveRecord::Base.maintain_test_schema
|
|
suppress_messages { load_schema_if_pending! }
|
|
end
|
|
end
|
|
|
|
def method_missing(name, *args, &block) #:nodoc:
|
|
nearest_delegate.send(name, *args, &block)
|
|
end
|
|
|
|
def migrate(direction)
|
|
new.migrate direction
|
|
end
|
|
|
|
# Disable the transaction wrapping this migration.
|
|
# You can still create your own transactions even after calling #disable_ddl_transaction!
|
|
#
|
|
# For more details read the {"Transactional Migrations" section above}[rdoc-ref:Migration].
|
|
def disable_ddl_transaction!
|
|
@disable_ddl_transaction = true
|
|
end
|
|
end
|
|
|
|
def disable_ddl_transaction #:nodoc:
|
|
self.class.disable_ddl_transaction
|
|
end
|
|
|
|
cattr_accessor :verbose
|
|
attr_accessor :name, :version
|
|
|
|
def initialize(name = self.class.name, version = nil)
|
|
@name = name
|
|
@version = version
|
|
@connection = nil
|
|
end
|
|
|
|
self.verbose = true
|
|
# instantiate the delegate object after initialize is defined
|
|
self.delegate = new
|
|
|
|
# Reverses the migration commands for the given block and
|
|
# the given migrations.
|
|
#
|
|
# The following migration will remove the table 'horses'
|
|
# and create the table 'apples' on the way up, and the reverse
|
|
# on the way down.
|
|
#
|
|
# class FixTLMigration < ActiveRecord::Migration[5.0]
|
|
# def change
|
|
# revert do
|
|
# create_table(:horses) do |t|
|
|
# t.text :content
|
|
# t.datetime :remind_at
|
|
# end
|
|
# end
|
|
# create_table(:apples) do |t|
|
|
# t.string :variety
|
|
# end
|
|
# end
|
|
# end
|
|
#
|
|
# Or equivalently, if +TenderloveMigration+ is defined as in the
|
|
# documentation for Migration:
|
|
#
|
|
# require_relative '20121212123456_tenderlove_migration'
|
|
#
|
|
# class FixupTLMigration < ActiveRecord::Migration[5.0]
|
|
# def change
|
|
# revert TenderloveMigration
|
|
#
|
|
# create_table(:apples) do |t|
|
|
# t.string :variety
|
|
# end
|
|
# end
|
|
# end
|
|
#
|
|
# This command can be nested.
|
|
def revert(*migration_classes)
|
|
run(*migration_classes.reverse, revert: true) unless migration_classes.empty?
|
|
if block_given?
|
|
if connection.respond_to? :revert
|
|
connection.revert { yield }
|
|
else
|
|
recorder = command_recorder
|
|
@connection = recorder
|
|
suppress_messages do
|
|
connection.revert { yield }
|
|
end
|
|
@connection = recorder.delegate
|
|
recorder.replay(self)
|
|
end
|
|
end
|
|
end
|
|
|
|
def reverting?
|
|
connection.respond_to?(:reverting) && connection.reverting
|
|
end
|
|
|
|
ReversibleBlockHelper = Struct.new(:reverting) do #:nodoc:
|
|
def up
|
|
yield unless reverting
|
|
end
|
|
|
|
def down
|
|
yield if reverting
|
|
end
|
|
end
|
|
|
|
# Used to specify an operation that can be run in one direction or another.
|
|
# Call the methods +up+ and +down+ of the yielded object to run a block
|
|
# only in one given direction.
|
|
# The whole block will be called in the right order within the migration.
|
|
#
|
|
# In the following example, the looping on users will always be done
|
|
# when the three columns 'first_name', 'last_name' and 'full_name' exist,
|
|
# even when migrating down:
|
|
#
|
|
# class SplitNameMigration < ActiveRecord::Migration[5.0]
|
|
# def change
|
|
# add_column :users, :first_name, :string
|
|
# add_column :users, :last_name, :string
|
|
#
|
|
# reversible do |dir|
|
|
# User.reset_column_information
|
|
# User.all.each do |u|
|
|
# dir.up { u.first_name, u.last_name = u.full_name.split(' ') }
|
|
# dir.down { u.full_name = "#{u.first_name} #{u.last_name}" }
|
|
# u.save
|
|
# end
|
|
# end
|
|
#
|
|
# revert { add_column :users, :full_name, :string }
|
|
# end
|
|
# end
|
|
def reversible
|
|
helper = ReversibleBlockHelper.new(reverting?)
|
|
execute_block { yield helper }
|
|
end
|
|
|
|
# Used to specify an operation that is only run when migrating up
|
|
# (for example, populating a new column with its initial values).
|
|
#
|
|
# In the following example, the new column +published+ will be given
|
|
# the value +true+ for all existing records.
|
|
#
|
|
# class AddPublishedToPosts < ActiveRecord::Migration[5.2]
|
|
# def change
|
|
# add_column :posts, :published, :boolean, default: false
|
|
# up_only do
|
|
# execute "update posts set published = 'true'"
|
|
# end
|
|
# end
|
|
# end
|
|
def up_only
|
|
execute_block { yield } unless reverting?
|
|
end
|
|
|
|
# Runs the given migration classes.
|
|
# Last argument can specify options:
|
|
# - :direction (default is :up)
|
|
# - :revert (default is false)
|
|
def run(*migration_classes)
|
|
opts = migration_classes.extract_options!
|
|
dir = opts[:direction] || :up
|
|
dir = (dir == :down ? :up : :down) if opts[:revert]
|
|
if reverting?
|
|
# If in revert and going :up, say, we want to execute :down without reverting, so
|
|
revert { run(*migration_classes, direction: dir, revert: true) }
|
|
else
|
|
migration_classes.each do |migration_class|
|
|
migration_class.new.exec_migration(connection, dir)
|
|
end
|
|
end
|
|
end
|
|
|
|
def up
|
|
self.class.delegate = self
|
|
return unless self.class.respond_to?(:up)
|
|
self.class.up
|
|
end
|
|
|
|
def down
|
|
self.class.delegate = self
|
|
return unless self.class.respond_to?(:down)
|
|
self.class.down
|
|
end
|
|
|
|
# Execute this migration in the named direction
|
|
def migrate(direction)
|
|
return unless respond_to?(direction)
|
|
|
|
case direction
|
|
when :up then announce "migrating"
|
|
when :down then announce "reverting"
|
|
end
|
|
|
|
time = nil
|
|
ActiveRecord::Base.connection_pool.with_connection do |conn|
|
|
time = Benchmark.measure do
|
|
exec_migration(conn, direction)
|
|
end
|
|
end
|
|
|
|
case direction
|
|
when :up then announce "migrated (%.4fs)" % time.real; write
|
|
when :down then announce "reverted (%.4fs)" % time.real; write
|
|
end
|
|
end
|
|
|
|
def exec_migration(conn, direction)
|
|
@connection = conn
|
|
if respond_to?(:change)
|
|
if direction == :down
|
|
revert { change }
|
|
else
|
|
change
|
|
end
|
|
else
|
|
send(direction)
|
|
end
|
|
ensure
|
|
@connection = nil
|
|
end
|
|
|
|
def write(text = "")
|
|
puts(text) if verbose
|
|
end
|
|
|
|
def announce(message)
|
|
text = "#{version} #{name}: #{message}"
|
|
length = [0, 75 - text.length].max
|
|
write "== %s %s" % [text, "=" * length]
|
|
end
|
|
|
|
# Takes a message argument and outputs it as is.
|
|
# A second boolean argument can be passed to specify whether to indent or not.
|
|
def say(message, subitem = false)
|
|
write "#{subitem ? " ->" : "--"} #{message}"
|
|
end
|
|
|
|
# Outputs text along with how long it took to run its block.
|
|
# If the block returns an integer it assumes it is the number of rows affected.
|
|
def say_with_time(message)
|
|
say(message)
|
|
result = nil
|
|
time = Benchmark.measure { result = yield }
|
|
say "%.4fs" % time.real, :subitem
|
|
say("#{result} rows", :subitem) if result.is_a?(Integer)
|
|
result
|
|
end
|
|
|
|
# Takes a block as an argument and suppresses any output generated by the block.
|
|
def suppress_messages
|
|
save, self.verbose = verbose, false
|
|
yield
|
|
ensure
|
|
self.verbose = save
|
|
end
|
|
|
|
def connection
|
|
@connection || ActiveRecord::Base.connection
|
|
end
|
|
|
|
def method_missing(method, *arguments, &block)
|
|
arg_list = arguments.map(&:inspect) * ", "
|
|
|
|
say_with_time "#{method}(#{arg_list})" do
|
|
unless connection.respond_to? :revert
|
|
unless arguments.empty? || [:execute, :enable_extension, :disable_extension].include?(method)
|
|
arguments[0] = proper_table_name(arguments.first, table_name_options)
|
|
if [:rename_table, :add_foreign_key].include?(method) ||
|
|
(method == :remove_foreign_key && !arguments.second.is_a?(Hash))
|
|
arguments[1] = proper_table_name(arguments.second, table_name_options)
|
|
end
|
|
end
|
|
end
|
|
return super unless connection.respond_to?(method)
|
|
connection.send(method, *arguments, &block)
|
|
end
|
|
end
|
|
|
|
def copy(destination, sources, options = {})
|
|
copied = []
|
|
schema_migration = options[:schema_migration] || ActiveRecord::SchemaMigration
|
|
|
|
FileUtils.mkdir_p(destination) unless File.exist?(destination)
|
|
|
|
destination_migrations = ActiveRecord::MigrationContext.new(destination, schema_migration).migrations
|
|
last = destination_migrations.last
|
|
sources.each do |scope, path|
|
|
source_migrations = ActiveRecord::MigrationContext.new(path, schema_migration).migrations
|
|
|
|
source_migrations.each do |migration|
|
|
source = File.binread(migration.filename)
|
|
inserted_comment = "# This migration comes from #{scope} (originally #{migration.version})\n"
|
|
magic_comments = +""
|
|
loop do
|
|
# If we have a magic comment in the original migration,
|
|
# insert our comment after the first newline(end of the magic comment line)
|
|
# so the magic keep working.
|
|
# Note that magic comments must be at the first line(except sh-bang).
|
|
source.sub!(/\A(?:#.*\b(?:en)?coding:\s*\S+|#\s*frozen_string_literal:\s*(?:true|false)).*\n/) do |magic_comment|
|
|
magic_comments << magic_comment; ""
|
|
end || break
|
|
end
|
|
source = "#{magic_comments}#{inserted_comment}#{source}"
|
|
|
|
if duplicate = destination_migrations.detect { |m| m.name == migration.name }
|
|
if options[:on_skip] && duplicate.scope != scope.to_s
|
|
options[:on_skip].call(scope, migration)
|
|
end
|
|
next
|
|
end
|
|
|
|
migration.version = next_migration_number(last ? last.version + 1 : 0).to_i
|
|
new_path = File.join(destination, "#{migration.version}_#{migration.name.underscore}.#{scope}.rb")
|
|
old_path, migration.filename = migration.filename, new_path
|
|
last = migration
|
|
|
|
File.binwrite(migration.filename, source)
|
|
copied << migration
|
|
options[:on_copy].call(scope, migration, old_path) if options[:on_copy]
|
|
destination_migrations << migration
|
|
end
|
|
end
|
|
|
|
copied
|
|
end
|
|
|
|
# Finds the correct table name given an Active Record object.
|
|
# Uses the Active Record object's own table_name, or pre/suffix from the
|
|
# options passed in.
|
|
def proper_table_name(name, options = {})
|
|
if name.respond_to? :table_name
|
|
name.table_name
|
|
else
|
|
"#{options[:table_name_prefix]}#{name}#{options[:table_name_suffix]}"
|
|
end
|
|
end
|
|
|
|
# Determines the version number of the next migration.
|
|
def next_migration_number(number)
|
|
if ActiveRecord::Base.timestamped_migrations
|
|
[Time.now.utc.strftime("%Y%m%d%H%M%S"), "%.14d" % number].max
|
|
else
|
|
SchemaMigration.normalize_migration_number(number)
|
|
end
|
|
end
|
|
|
|
# Builds a hash for use in ActiveRecord::Migration#proper_table_name using
|
|
# the Active Record object's table_name prefix and suffix
|
|
def table_name_options(config = ActiveRecord::Base) #:nodoc:
|
|
{
|
|
table_name_prefix: config.table_name_prefix,
|
|
table_name_suffix: config.table_name_suffix
|
|
}
|
|
end
|
|
|
|
private
|
|
def execute_block
|
|
if connection.respond_to? :execute_block
|
|
super # use normal delegation to record the block
|
|
else
|
|
yield
|
|
end
|
|
end
|
|
|
|
def command_recorder
|
|
CommandRecorder.new(connection)
|
|
end
|
|
end
|
|
|
|
# MigrationProxy is used to defer loading of the actual migration classes
|
|
# until they are needed
|
|
MigrationProxy = Struct.new(:name, :version, :filename, :scope) do
|
|
def initialize(name, version, filename, scope)
|
|
super
|
|
@migration = nil
|
|
end
|
|
|
|
def basename
|
|
File.basename(filename)
|
|
end
|
|
|
|
def mtime
|
|
File.mtime filename
|
|
end
|
|
|
|
delegate :migrate, :announce, :write, :disable_ddl_transaction, to: :migration
|
|
|
|
private
|
|
def migration
|
|
@migration ||= load_migration
|
|
end
|
|
|
|
def load_migration
|
|
require(File.expand_path(filename))
|
|
name.constantize.new(name, version)
|
|
end
|
|
end
|
|
|
|
class NullMigration < MigrationProxy #:nodoc:
|
|
def initialize
|
|
super(nil, 0, nil, nil)
|
|
end
|
|
|
|
def mtime
|
|
0
|
|
end
|
|
end
|
|
|
|
class MigrationContext #:nodoc:
|
|
attr_reader :migrations_paths, :schema_migration
|
|
|
|
def initialize(migrations_paths, schema_migration)
|
|
@migrations_paths = migrations_paths
|
|
@schema_migration = schema_migration
|
|
end
|
|
|
|
def migrate(target_version = nil, &block)
|
|
case
|
|
when target_version.nil?
|
|
up(target_version, &block)
|
|
when current_version == 0 && target_version == 0
|
|
[]
|
|
when current_version > target_version
|
|
down(target_version, &block)
|
|
else
|
|
up(target_version, &block)
|
|
end
|
|
end
|
|
|
|
def rollback(steps = 1)
|
|
move(:down, steps)
|
|
end
|
|
|
|
def forward(steps = 1)
|
|
move(:up, steps)
|
|
end
|
|
|
|
def up(target_version = nil)
|
|
selected_migrations = if block_given?
|
|
migrations.select { |m| yield m }
|
|
else
|
|
migrations
|
|
end
|
|
|
|
Migrator.new(:up, selected_migrations, schema_migration, target_version).migrate
|
|
end
|
|
|
|
def down(target_version = nil)
|
|
selected_migrations = if block_given?
|
|
migrations.select { |m| yield m }
|
|
else
|
|
migrations
|
|
end
|
|
|
|
Migrator.new(:down, selected_migrations, schema_migration, target_version).migrate
|
|
end
|
|
|
|
def run(direction, target_version)
|
|
Migrator.new(direction, migrations, schema_migration, target_version).run
|
|
end
|
|
|
|
def open
|
|
Migrator.new(:up, migrations, schema_migration)
|
|
end
|
|
|
|
def get_all_versions
|
|
if schema_migration.table_exists?
|
|
schema_migration.all_versions.map(&:to_i)
|
|
else
|
|
[]
|
|
end
|
|
end
|
|
|
|
def current_version
|
|
get_all_versions.max || 0
|
|
rescue ActiveRecord::NoDatabaseError
|
|
end
|
|
|
|
def needs_migration?
|
|
(migrations.collect(&:version) - get_all_versions).size > 0
|
|
end
|
|
|
|
def any_migrations?
|
|
migrations.any?
|
|
end
|
|
|
|
def last_migration #:nodoc:
|
|
migrations.last || NullMigration.new
|
|
end
|
|
|
|
def migrations
|
|
migrations = migration_files.map do |file|
|
|
version, name, scope = parse_migration_filename(file)
|
|
raise IllegalMigrationNameError.new(file) unless version
|
|
version = version.to_i
|
|
name = name.camelize
|
|
|
|
MigrationProxy.new(name, version, file, scope)
|
|
end
|
|
|
|
migrations.sort_by(&:version)
|
|
end
|
|
|
|
def migrations_status
|
|
db_list = schema_migration.normalized_versions
|
|
|
|
file_list = migration_files.map do |file|
|
|
version, name, scope = parse_migration_filename(file)
|
|
raise IllegalMigrationNameError.new(file) unless version
|
|
version = schema_migration.normalize_migration_number(version)
|
|
status = db_list.delete(version) ? "up" : "down"
|
|
[status, version, (name + scope).humanize]
|
|
end.compact
|
|
|
|
db_list.map! do |version|
|
|
["up", version, "********** NO FILE **********"]
|
|
end
|
|
|
|
(db_list + file_list).sort_by { |_, version, _| version }
|
|
end
|
|
|
|
def current_environment
|
|
ActiveRecord::ConnectionHandling::DEFAULT_ENV.call
|
|
end
|
|
|
|
def protected_environment?
|
|
ActiveRecord::Base.protected_environments.include?(last_stored_environment) if last_stored_environment
|
|
end
|
|
|
|
def last_stored_environment
|
|
return nil if current_version == 0
|
|
raise NoEnvironmentInSchemaError unless ActiveRecord::InternalMetadata.table_exists?
|
|
|
|
environment = ActiveRecord::InternalMetadata[:environment]
|
|
raise NoEnvironmentInSchemaError unless environment
|
|
environment
|
|
end
|
|
|
|
private
|
|
def migration_files
|
|
paths = Array(migrations_paths)
|
|
Dir[*paths.flat_map { |path| "#{path}/**/[0-9]*_*.rb" }]
|
|
end
|
|
|
|
def parse_migration_filename(filename)
|
|
File.basename(filename).scan(Migration::MigrationFilenameRegexp).first
|
|
end
|
|
|
|
def move(direction, steps)
|
|
migrator = Migrator.new(direction, migrations, schema_migration)
|
|
|
|
if current_version != 0 && !migrator.current_migration
|
|
raise UnknownMigrationVersionError.new(current_version)
|
|
end
|
|
|
|
start_index =
|
|
if current_version == 0
|
|
0
|
|
else
|
|
migrator.migrations.index(migrator.current_migration)
|
|
end
|
|
|
|
finish = migrator.migrations[start_index + steps]
|
|
version = finish ? finish.version : 0
|
|
send(direction, version)
|
|
end
|
|
end
|
|
|
|
class Migrator # :nodoc:
|
|
class << self
|
|
attr_accessor :migrations_paths
|
|
|
|
# For cases where a table doesn't exist like loading from schema cache
|
|
def current_version
|
|
MigrationContext.new(migrations_paths, SchemaMigration).current_version
|
|
end
|
|
end
|
|
|
|
self.migrations_paths = ["db/migrate"]
|
|
|
|
def initialize(direction, migrations, schema_migration, target_version = nil)
|
|
@direction = direction
|
|
@target_version = target_version
|
|
@migrated_versions = nil
|
|
@migrations = migrations
|
|
@schema_migration = schema_migration
|
|
|
|
validate(@migrations)
|
|
|
|
@schema_migration.create_table
|
|
ActiveRecord::InternalMetadata.create_table
|
|
end
|
|
|
|
def current_version
|
|
migrated.max || 0
|
|
end
|
|
|
|
def current_migration
|
|
migrations.detect { |m| m.version == current_version }
|
|
end
|
|
alias :current :current_migration
|
|
|
|
def run
|
|
if use_advisory_lock?
|
|
with_advisory_lock { run_without_lock }
|
|
else
|
|
run_without_lock
|
|
end
|
|
end
|
|
|
|
def migrate
|
|
if use_advisory_lock?
|
|
with_advisory_lock { migrate_without_lock }
|
|
else
|
|
migrate_without_lock
|
|
end
|
|
end
|
|
|
|
def runnable
|
|
runnable = migrations[start..finish]
|
|
if up?
|
|
runnable.reject { |m| ran?(m) }
|
|
else
|
|
# skip the last migration if we're headed down, but not ALL the way down
|
|
runnable.pop if target
|
|
runnable.find_all { |m| ran?(m) }
|
|
end
|
|
end
|
|
|
|
def migrations
|
|
down? ? @migrations.reverse : @migrations.sort_by(&:version)
|
|
end
|
|
|
|
def pending_migrations
|
|
already_migrated = migrated
|
|
migrations.reject { |m| already_migrated.include?(m.version) }
|
|
end
|
|
|
|
def migrated
|
|
@migrated_versions || load_migrated
|
|
end
|
|
|
|
def load_migrated
|
|
@migrated_versions = Set.new(@schema_migration.all_versions.map(&:to_i))
|
|
end
|
|
|
|
private
|
|
# Used for running a specific migration.
|
|
def run_without_lock
|
|
migration = migrations.detect { |m| m.version == @target_version }
|
|
raise UnknownMigrationVersionError.new(@target_version) if migration.nil?
|
|
result = execute_migration_in_transaction(migration, @direction)
|
|
|
|
record_environment
|
|
result
|
|
end
|
|
|
|
# Used for running multiple migrations up to or down to a certain value.
|
|
def migrate_without_lock
|
|
if invalid_target?
|
|
raise UnknownMigrationVersionError.new(@target_version)
|
|
end
|
|
|
|
result = runnable.each do |migration|
|
|
execute_migration_in_transaction(migration, @direction)
|
|
end
|
|
|
|
record_environment
|
|
result
|
|
end
|
|
|
|
# Stores the current environment in the database.
|
|
def record_environment
|
|
return if down?
|
|
ActiveRecord::InternalMetadata[:environment] = ActiveRecord::Base.connection.migration_context.current_environment
|
|
end
|
|
|
|
def ran?(migration)
|
|
migrated.include?(migration.version.to_i)
|
|
end
|
|
|
|
# Return true if a valid version is not provided.
|
|
def invalid_target?
|
|
@target_version && @target_version != 0 && !target
|
|
end
|
|
|
|
def execute_migration_in_transaction(migration, direction)
|
|
return if down? && !migrated.include?(migration.version.to_i)
|
|
return if up? && migrated.include?(migration.version.to_i)
|
|
|
|
Base.logger.info "Migrating to #{migration.name} (#{migration.version})" if Base.logger
|
|
|
|
ddl_transaction(migration) do
|
|
migration.migrate(direction)
|
|
record_version_state_after_migrating(migration.version)
|
|
end
|
|
rescue => e
|
|
msg = +"An error has occurred, "
|
|
msg << "this and " if use_transaction?(migration)
|
|
msg << "all later migrations canceled:\n\n#{e}"
|
|
raise StandardError, msg, e.backtrace
|
|
end
|
|
|
|
def target
|
|
migrations.detect { |m| m.version == @target_version }
|
|
end
|
|
|
|
def finish
|
|
migrations.index(target) || migrations.size - 1
|
|
end
|
|
|
|
def start
|
|
up? ? 0 : (migrations.index(current) || 0)
|
|
end
|
|
|
|
def validate(migrations)
|
|
name, = migrations.group_by(&:name).find { |_, v| v.length > 1 }
|
|
raise DuplicateMigrationNameError.new(name) if name
|
|
|
|
version, = migrations.group_by(&:version).find { |_, v| v.length > 1 }
|
|
raise DuplicateMigrationVersionError.new(version) if version
|
|
end
|
|
|
|
def record_version_state_after_migrating(version)
|
|
if down?
|
|
migrated.delete(version)
|
|
@schema_migration.delete_by(version: version.to_s)
|
|
else
|
|
migrated << version
|
|
@schema_migration.create!(version: version.to_s)
|
|
end
|
|
end
|
|
|
|
def up?
|
|
@direction == :up
|
|
end
|
|
|
|
def down?
|
|
@direction == :down
|
|
end
|
|
|
|
# Wrap the migration in a transaction only if supported by the adapter.
|
|
def ddl_transaction(migration)
|
|
if use_transaction?(migration)
|
|
Base.transaction { yield }
|
|
else
|
|
yield
|
|
end
|
|
end
|
|
|
|
def use_transaction?(migration)
|
|
!migration.disable_ddl_transaction && Base.connection.supports_ddl_transactions?
|
|
end
|
|
|
|
def use_advisory_lock?
|
|
Base.connection.advisory_locks_enabled?
|
|
end
|
|
|
|
def with_advisory_lock
|
|
lock_id = generate_migrator_advisory_lock_id
|
|
connection = Base.connection
|
|
got_lock = connection.get_advisory_lock(lock_id)
|
|
raise ConcurrentMigrationError unless got_lock
|
|
load_migrated # reload schema_migrations to be sure it wasn't changed by another process before we got the lock
|
|
yield
|
|
ensure
|
|
if got_lock && !connection.release_advisory_lock(lock_id)
|
|
raise ConcurrentMigrationError.new(
|
|
ConcurrentMigrationError::RELEASE_LOCK_FAILED_MESSAGE
|
|
)
|
|
end
|
|
end
|
|
|
|
MIGRATOR_SALT = 2053462845
|
|
def generate_migrator_advisory_lock_id
|
|
db_name_hash = Zlib.crc32(Base.connection.current_database)
|
|
MIGRATOR_SALT * db_name_hash
|
|
end
|
|
end
|
|
end
|