jro_apps/redmine Commit - r15568:2b70d977052a

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#

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#

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# Permission is hereby granted, free of charge, to any person obtaining

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# Permission is hereby granted, free of charge, to any person obtaining

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# a copy of this software and associated documentation files (the

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# a copy of this software and associated documentation files (the

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# "Software"), to deal in the Software without restriction, including

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# "Software"), to deal in the Software without restriction, including

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# without limitation the rights to use, copy, modify, merge, publish,

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# without limitation the rights to use, copy, modify, merge, publish,

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# distribute, sublicense, and/or sell copies of the Software, and to

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# distribute, sublicense, and/or sell copies of the Software, and to

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# permit persons to whom the Software is furnished to do so, subject to

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# permit persons to whom the Software is furnished to do so, subject to

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# the following conditions:

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# the following conditions:

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#

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#

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# The above copyright notice and this permission notice shall be

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# The above copyright notice and this permission notice shall be

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# included in all copies or substantial portions of the Software.

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# included in all copies or substantial portions of the Software.

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#

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#

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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

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# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

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# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

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# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

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# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

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# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE

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# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE

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# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION

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# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION

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# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION

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# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION

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# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

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# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

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module ActiveRecord #:nodoc:

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module ActiveRecord #:nodoc:

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module Acts #:nodoc:

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module Acts #:nodoc:

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# Specify this act if you want to save a copy of the row in a versioned table. This assumes there is a

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# Specify this act if you want to save a copy of the row in a versioned table. This assumes there is a

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# versioned table ready and that your model has a version field. This works with optimistic locking if the lock_version

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# versioned table ready and that your model has a version field. This works with optimistic locking if the lock_version

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# column is present as well.

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# column is present as well.

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#

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#

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# The class for the versioned model is derived the first time it is seen. Therefore, if you change your database schema you have to restart

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# The class for the versioned model is derived the first time it is seen. Therefore, if you change your database schema you have to restart

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# your container for the changes to be reflected. In development mode this usually means restarting WEBrick.

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# your container for the changes to be reflected. In development mode this usually means restarting WEBrick.

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#

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#

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# class Page < ActiveRecord::Base

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# class Page < ActiveRecord::Base

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# # assumes pages_versions table

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# # assumes pages_versions table

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# acts_as_versioned

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# acts_as_versioned

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# end

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# end

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#

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#

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# Example:

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# Example:

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#

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#

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# page = Page.create(:title => 'hello world!')

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# page = Page.create(:title => 'hello world!')

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# page.version # => 1

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# page.version # => 1

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#

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#

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# page.title = 'hello world'

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# page.title = 'hello world'

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# page.save

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# page.save

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# page.version # => 2

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# page.version # => 2

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# page.versions.size # => 2

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# page.versions.size # => 2

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#

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#

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# page.revert_to(1) # using version number

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# page.revert_to(1) # using version number

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# page.title # => 'hello world!'

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# page.title # => 'hello world!'

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#

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#

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# page.revert_to(page.versions.last) # using versioned instance

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# page.revert_to(page.versions.last) # using versioned instance

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# page.title # => 'hello world'

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# page.title # => 'hello world'

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#

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#

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# page.versions.earliest # efficient query to find the first version

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# page.versions.earliest # efficient query to find the first version

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# page.versions.latest # efficient query to find the most recently created version

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# page.versions.latest # efficient query to find the most recently created version

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#

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#

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#

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#

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# Simple Queries to page between versions

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# Simple Queries to page between versions

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#

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#

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# page.versions.before(version)

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# page.versions.before(version)

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# page.versions.after(version)

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# page.versions.after(version)

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#

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#

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# Access the previous/next versions from the versioned model itself

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# Access the previous/next versions from the versioned model itself

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#

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#

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# version = page.versions.latest

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# version = page.versions.latest

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# version.previous # go back one version

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# version.previous # go back one version

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# version.next # go forward one version

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# version.next # go forward one version

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#

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#

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# See ActiveRecord::Acts::Versioned::ClassMethods#acts_as_versioned for configuration options

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# See ActiveRecord::Acts::Versioned::ClassMethods#acts_as_versioned for configuration options

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module Versioned

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module Versioned

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CALLBACKS = [:set_new_version, :save_version_on_create, :save_version?, :clear_altered_attributes]

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CALLBACKS = [:set_new_version, :save_version_on_create, :save_version?, :clear_altered_attributes]

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def self.included(base) # :nodoc:

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def self.included(base) # :nodoc:

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base.extend ClassMethods

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base.extend ClassMethods

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end

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end

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module ClassMethods

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module ClassMethods

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# == Configuration options

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# == Configuration options

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#

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#

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# * <tt>class_name</tt> - versioned model class name (default: PageVersion in the above example)

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# * <tt>class_name</tt> - versioned model class name (default: PageVersion in the above example)

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# * <tt>table_name</tt> - versioned model table name (default: page_versions in the above example)

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# * <tt>table_name</tt> - versioned model table name (default: page_versions in the above example)

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# * <tt>foreign_key</tt> - foreign key used to relate the versioned model to the original model (default: page_id in the above example)

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# * <tt>foreign_key</tt> - foreign key used to relate the versioned model to the original model (default: page_id in the above example)

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# * <tt>inheritance_column</tt> - name of the column to save the model's inheritance_column value for STI. (default: versioned_type)

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# * <tt>inheritance_column</tt> - name of the column to save the model's inheritance_column value for STI. (default: versioned_type)

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# * <tt>version_column</tt> - name of the column in the model that keeps the version number (default: version)

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# * <tt>version_column</tt> - name of the column in the model that keeps the version number (default: version)

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# * <tt>sequence_name</tt> - name of the custom sequence to be used by the versioned model.

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# * <tt>sequence_name</tt> - name of the custom sequence to be used by the versioned model.

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# * <tt>limit</tt> - number of revisions to keep, defaults to unlimited

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# * <tt>limit</tt> - number of revisions to keep, defaults to unlimited

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# * <tt>if</tt> - symbol of method to check before saving a new version. If this method returns false, a new version is not saved.

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# * <tt>if</tt> - symbol of method to check before saving a new version. If this method returns false, a new version is not saved.

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# For finer control, pass either a Proc or modify Model#version_condition_met?

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# For finer control, pass either a Proc or modify Model#version_condition_met?

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#

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#

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# acts_as_versioned :if => Proc.new { |auction| !auction.expired? }

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# acts_as_versioned :if => Proc.new { |auction| !auction.expired? }

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#

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#

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# or...

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# or...

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#

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#

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# class Auction

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# class Auction

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# def version_condition_met? # totally bypasses the <tt>:if</tt> option

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# def version_condition_met? # totally bypasses the <tt>:if</tt> option

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# !expired?

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# !expired?

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# end

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# end

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# end

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# end

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#

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#

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# * <tt>if_changed</tt> - Simple way of specifying attributes that are required to be changed before saving a model. This takes

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# * <tt>if_changed</tt> - Simple way of specifying attributes that are required to be changed before saving a model. This takes

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# either a symbol or array of symbols. WARNING - This will attempt to overwrite any attribute setters you may have.

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# either a symbol or array of symbols. WARNING - This will attempt to overwrite any attribute setters you may have.

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# Use this instead if you want to write your own attribute setters (and ignore if_changed):

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# Use this instead if you want to write your own attribute setters (and ignore if_changed):

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#

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#

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# def name=(new_name)

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# def name=(new_name)

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# write_changed_attribute :name, new_name

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# write_changed_attribute :name, new_name

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# end

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# end

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#

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#

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# * <tt>extend</tt> - Lets you specify a module to be mixed in both the original and versioned models. You can also just pass a block

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# * <tt>extend</tt> - Lets you specify a module to be mixed in both the original and versioned models. You can also just pass a block

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# to create an anonymous mixin:

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# to create an anonymous mixin:

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#

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#

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# class Auction

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# class Auction

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# acts_as_versioned do

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# acts_as_versioned do

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# def started?

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# def started?

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# !started_at.nil?

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# !started_at.nil?

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# end

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# end

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# end

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# end

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# end

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# end

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#

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#

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# or...

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# or...

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#

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#

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# module AuctionExtension

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# module AuctionExtension

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# def started?

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# def started?

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# !started_at.nil?

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# !started_at.nil?

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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 Auction

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# class Auction

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# acts_as_versioned :extend => AuctionExtension

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# acts_as_versioned :extend => AuctionExtension

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# end

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# end

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#

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#

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# Example code:

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# Example code:

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#

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#

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# @auction = Auction.find(1)

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# @auction = Auction.find(1)

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# @auction.started?

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# @auction.started?

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# @auction.versions.first.started?

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# @auction.versions.first.started?

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#

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#

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# == Database Schema

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# == Database Schema

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#

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#

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# The model that you're versioning needs to have a 'version' attribute. The model is versioned

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# The model that you're versioning needs to have a 'version' attribute. The model is versioned

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# into a table called #{model}_versions where the model name is singlular. The _versions table should

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# into a table called #{model}_versions where the model name is singlular. The _versions table should

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# contain all the fields you want versioned, the same version column, and a #{model}_id foreign key field.

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# contain all the fields you want versioned, the same version column, and a #{model}_id foreign key field.

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#

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#

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# A lock_version field is also accepted if your model uses Optimistic Locking. If your table uses Single Table inheritance,

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# A lock_version field is also accepted if your model uses Optimistic Locking. If your table uses Single Table inheritance,

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# then that field is reflected in the versioned model as 'versioned_type' by default.

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# then that field is reflected in the versioned model as 'versioned_type' by default.

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#

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#

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# Acts_as_versioned comes prepared with the ActiveRecord::Acts::Versioned::ActMethods::ClassMethods#create_versioned_table

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# Acts_as_versioned comes prepared with the ActiveRecord::Acts::Versioned::ActMethods::ClassMethods#create_versioned_table

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# method, perfect for a migration. It will also create the version column if the main model does not already have it.

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# method, perfect for a migration. It will also create the version column if the main model does not already have it.

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#

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#

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# class AddVersions < ActiveRecord::Migration

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# class AddVersions < ActiveRecord::Migration

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# def self.up

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# def self.up

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# # create_versioned_table takes the same options hash

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# # create_versioned_table takes the same options hash

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# # that create_table does

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# # that create_table does

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# Post.create_versioned_table

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# Post.create_versioned_table

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# end

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# end

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#

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#

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# def self.down

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# def self.down

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# Post.drop_versioned_table

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# Post.drop_versioned_table

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# end

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# end

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# end

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# end

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#

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#

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# == Changing What Fields Are Versioned

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# == Changing What Fields Are Versioned

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#

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#

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# By default, acts_as_versioned will version all but these fields:

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# By default, acts_as_versioned will version all but these fields:

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#

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#

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# [self.primary_key, inheritance_column, 'version', 'lock_version', versioned_inheritance_column]

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# [self.primary_key, inheritance_column, 'version', 'lock_version', versioned_inheritance_column]

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#

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#

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# You can add or change those by modifying #non_versioned_columns. Note that this takes strings and not symbols.

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# You can add or change those by modifying #non_versioned_columns. Note that this takes strings and not symbols.

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#

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#

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# class Post < ActiveRecord::Base

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# class Post < ActiveRecord::Base

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# acts_as_versioned

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# acts_as_versioned

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# self.non_versioned_columns << 'comments_count'

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# self.non_versioned_columns << 'comments_count'

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# end

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# end

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#

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#

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def acts_as_versioned(options = {}, &extension)

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def acts_as_versioned(options = {}, &extension)

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# don't allow multiple calls

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# don't allow multiple calls

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return if self.included_modules.include?(ActiveRecord::Acts::Versioned::ActMethods)

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return if self.included_modules.include?(ActiveRecord::Acts::Versioned::ActMethods)

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send :include, ActiveRecord::Acts::Versioned::ActMethods

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send :include, ActiveRecord::Acts::Versioned::ActMethods

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cattr_accessor :versioned_class_name, :versioned_foreign_key, :versioned_table_name, :versioned_inheritance_column,

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cattr_accessor :versioned_class_name, :versioned_foreign_key, :versioned_table_name, :versioned_inheritance_column,

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:version_column, :max_version_limit, :track_altered_attributes, :version_condition, :version_sequence_name, :non_versioned_columns,

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:version_column, :max_version_limit, :track_altered_attributes, :version_condition, :version_sequence_name, :non_versioned_columns,

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:version_association_options

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:version_association_options

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# legacy

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# legacy

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alias_method :non_versioned_fields, :non_versioned_columns

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alias_method :non_versioned_fields, :non_versioned_columns

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alias_method :non_versioned_fields=, :non_versioned_columns=

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alias_method :non_versioned_fields=, :non_versioned_columns=

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class << self

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class << self

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alias_method :non_versioned_fields, :non_versioned_columns

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alias_method :non_versioned_fields, :non_versioned_columns

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alias_method :non_versioned_fields=, :non_versioned_columns=

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alias_method :non_versioned_fields=, :non_versioned_columns=

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end

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end

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send :attr_accessor, :altered_attributes

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send :attr_accessor, :altered_attributes

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self.versioned_class_name = options[:class_name] || "Version"

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self.versioned_class_name = options[:class_name] || "Version"

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self.versioned_foreign_key = options[:foreign_key] || self.to_s.foreign_key

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self.versioned_foreign_key = options[:foreign_key] || self.to_s.foreign_key

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self.versioned_table_name = options[:table_name] || "#{table_name_prefix}#{base_class.name.demodulize.underscore}_versions#{table_name_suffix}"

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self.versioned_table_name = options[:table_name] || "#{table_name_prefix}#{base_class.name.demodulize.underscore}_versions#{table_name_suffix}"

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self.versioned_inheritance_column = options[:inheritance_column] || "versioned_#{inheritance_column}"

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self.versioned_inheritance_column = options[:inheritance_column] || "versioned_#{inheritance_column}"

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self.version_column = options[:version_column] || 'version'

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self.version_column = options[:version_column] || 'version'

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self.version_sequence_name = options[:sequence_name]

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self.version_sequence_name = options[:sequence_name]

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self.max_version_limit = options[:limit].to_i

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self.max_version_limit = options[:limit].to_i

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self.version_condition = options[:if] || true

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self.version_condition = options[:if] || true

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self.non_versioned_columns = [self.primary_key, inheritance_column, 'version', 'lock_version', versioned_inheritance_column]

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self.non_versioned_columns = [self.primary_key, inheritance_column, 'version', 'lock_version', versioned_inheritance_column]

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self.version_association_options = {

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self.version_association_options = {

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:class_name => "#{self.to_s}::#{versioned_class_name}",

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:class_name => "#{self.to_s}::#{versioned_class_name}",

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:foreign_key => versioned_foreign_key,

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:foreign_key => versioned_foreign_key,

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:dependent => :delete_all

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:dependent => :delete_all

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}.merge(options[:association_options] || {})

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}.merge(options[:association_options] || {})

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if block_given?

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if block_given?

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extension_module_name = "#{versioned_class_name}Extension"

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extension_module_name = "#{versioned_class_name}Extension"

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silence_warnings do

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silence_warnings do

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self.const_set(extension_module_name, Module.new(&extension))

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self.const_set(extension_module_name, Module.new(&extension))

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end

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end

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options[:extend] = self.const_get(extension_module_name)

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options[:extend] = self.const_get(extension_module_name)

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end

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end

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class_eval do

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class_eval do

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has_many :versions, version_association_options do

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has_many :versions, version_association_options do

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# finds earliest version of this record

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# finds earliest version of this record

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def earliest

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def earliest

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@earliest ||= order('version').first

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@earliest ||= order('version').first

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end

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end

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# find latest version of this record

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# find latest version of this record

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def latest

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def latest

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@latest ||= order('version desc').first

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@latest ||= order('version desc').first

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end

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end

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end

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end

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before_save :set_new_version

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before_save :set_new_version

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after_create :save_version_on_create

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after_create :save_version_on_create

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after_update :save_version

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after_update :save_version

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after_save :clear_old_versions

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after_save :clear_old_versions

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after_save :clear_altered_attributes

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after_save :clear_altered_attributes

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unless options[:if_changed].nil?

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unless options[:if_changed].nil?

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self.track_altered_attributes = true

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self.track_altered_attributes = true

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options[:if_changed] = [options[:if_changed]] unless options[:if_changed].is_a?(Array)

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options[:if_changed] = [options[:if_changed]] unless options[:if_changed].is_a?(Array)

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options[:if_changed].each do |attr_name|

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options[:if_changed].each do |attr_name|

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define_method("#{attr_name}=") do |value|

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define_method("#{attr_name}=") do |value|

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write_changed_attribute attr_name, value

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write_changed_attribute attr_name, value

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end

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end

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end

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end

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end

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end

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include options[:extend] if options[:extend].is_a?(Module)

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include options[:extend] if options[:extend].is_a?(Module)

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end

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end

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# create the dynamic versioned model

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# create the dynamic versioned model

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const_set(versioned_class_name, Class.new(ActiveRecord::Base)).class_eval do

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const_set(versioned_class_name, Class.new(ActiveRecord::Base)).class_eval do

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def self.reloadable? ; false ; end

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def self.reloadable? ; false ; end

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# find first version before the given version

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# find first version before the given version

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def self.before(version)

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def self.before(version)

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order('version desc').

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order('version desc').

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where("#{original_class.versioned_foreign_key} = ? and version < ?", version.send(original_class.versioned_foreign_key), version.version).

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where("#{original_class.versioned_foreign_key} = ? and version < ?", version.send(original_class.versioned_foreign_key), version.version).

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first

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first

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end

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end

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# find first version after the given version.

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# find first version after the given version.

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def self.after(version)

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def self.after(version)

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order('version').

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order('version').

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where("#{original_class.versioned_foreign_key} = ? and version > ?", version.send(original_class.versioned_foreign_key), version.version).

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where("#{original_class.versioned_foreign_key} = ? and version > ?", version.send(original_class.versioned_foreign_key), version.version).

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first

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first

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end

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end

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def previous

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def previous

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self.class.before(self)

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self.class.before(self)

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end

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end

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def next

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def next

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self.class.after(self)

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self.class.after(self)

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end

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end

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def versions_count

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def versions_count

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page.version

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page.version

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end

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end

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end

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end

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versioned_class.cattr_accessor :original_class

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versioned_class.cattr_accessor :original_class

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versioned_class.original_class = self

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versioned_class.original_class = self

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versioned_class.table_name = versioned_table_name

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versioned_class.table_name = versioned_table_name

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versioned_class.belongs_to self.to_s.demodulize.underscore.to_sym,

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versioned_class.belongs_to self.to_s.demodulize.underscore.to_sym,

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:class_name => "::#{self.to_s}",

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:class_name => "::#{self.to_s}",

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:foreign_key => versioned_foreign_key

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:foreign_key => versioned_foreign_key

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versioned_class.send :include, options[:extend] if options[:extend].is_a?(Module)

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versioned_class.send :include, options[:extend] if options[:extend].is_a?(Module)

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versioned_class.set_sequence_name version_sequence_name if version_sequence_name

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versioned_class.set_sequence_name version_sequence_name if version_sequence_name

284

end

284

end

285

end

285

end

286

287

module ActMethods

287

module ActMethods

288

def self.included(base) # :nodoc:

288

def self.included(base) # :nodoc:

289

base.extend ClassMethods

289

base.extend ClassMethods

290

end

290

end

291

292

# Finds a specific version of this record

292

# Finds a specific version of this record

293

def find_version(version = nil)

293

def find_version(version = nil)

294

self.class.find_version(id, version)

294

self.class.find_version(id, version)

295

end

295

end

296

297

# Saves a version of the model if applicable

297

# Saves a version of the model if applicable

298

def save_version

298

def save_version

299

save_version_on_create if save_version?

299

save_version_on_create if save_version?

300

end

300

end

301

302

# Saves a version of the model in the versioned table. This is called in the after_save callback by default

302

# Saves a version of the model in the versioned table. This is called in the after_save callback by default

303

def save_version_on_create

303

def save_version_on_create

304

rev = self.class.versioned_class.new

304

rev = self.class.versioned_class.new

305

self.clone_versioned_model(self, rev)

305

self.clone_versioned_model(self, rev)

306

rev.version = send(self.class.version_column)

306

rev.version = send(self.class.version_column)

307

rev.send("#{self.class.versioned_foreign_key}=", self.id)

307

rev.send("#{self.class.versioned_foreign_key}=", self.id)

308

rev.save

308

rev.save

309

end

309

end

310

311

# Clears old revisions if a limit is set with the :limit option in <tt>acts_as_versioned</tt>.

311

# Clears old revisions if a limit is set with the :limit option in <tt>acts_as_versioned</tt>.

312

# Override this method to set your own criteria for clearing old versions.

312

# Override this method to set your own criteria for clearing old versions.

313

def clear_old_versions

313

def clear_old_versions

314

return if self.class.max_version_limit == 0

314

return if self.class.max_version_limit == 0

315

excess_baggage = send(self.class.version_column).to_i - self.class.max_version_limit

315

excess_baggage = send(self.class.version_column).to_i - self.class.max_version_limit

316

if excess_baggage > 0

316

if excess_baggage > 0

317

sql = "DELETE FROM #{self.class.versioned_table_name} WHERE version <= #{excess_baggage} AND #{self.class.versioned_foreign_key} = #{self.id}"

317

sql = "DELETE FROM #{self.class.versioned_table_name} WHERE version <= #{excess_baggage} AND #{self.class.versioned_foreign_key} = #{self.id}"

318

self.class.versioned_class.connection.execute sql

318

self.class.versioned_class.connection.execute sql

319

end

319

end

320

end

320

end

321

322

def versions_count

322

def versions_count

323

version

323

version

324

end

324

end

325

326

# Reverts a model to a given version. Takes either a version number or an instance of the versioned model

326

# Reverts a model to a given version. Takes either a version number or an instance of the versioned model

327

def revert_to(version)

327

def revert_to(version)

328

if version.is_a?(self.class.versioned_class)

328

if version.is_a?(self.class.versioned_class)

329

return false unless version.send(self.class.versioned_foreign_key) == self.id and !version.new_record?

329

return false unless version.send(self.class.versioned_foreign_key) == self.id and !version.new_record?

330

else

330

else

331

return false unless version = versions.find_by_version(version)

331

return false unless version = versions.find_by_version(version)

332

end

332

end

333

self.clone_versioned_model(version, self)

333

self.clone_versioned_model(version, self)

334

self.send("#{self.class.version_column}=", version.version)

334

self.send("#{self.class.version_column}=", version.version)

335

true

335

true

336

end

336

end

337

338

# Reverts a model to a given version and saves the model.

338

# Reverts a model to a given version and saves the model.

339

# Takes either a version number or an instance of the versioned model

339

# Takes either a version number or an instance of the versioned model

340

def revert_to!(version)

340

def revert_to!(version)

341

revert_to(version) ? save_without_revision : false

341

revert_to(version) ? save_without_revision : false

342

end

342

end

343

344

# Temporarily turns off Optimistic Locking while saving. Used when reverting so that a new version is not created.

344

# Temporarily turns off Optimistic Locking while saving. Used when reverting so that a new version is not created.

345

def save_without_revision

345

def save_without_revision

346

save_without_revision!

346

save_without_revision!

347

true

347

true

348

rescue

348

rescue

349

false

349

false

350

end

350

end

351

352

def save_without_revision!

352

def save_without_revision!

353

without_locking do

353

without_locking do

354

without_revision do

354

without_revision do

355

save!

355

save!

356

end

356

end

357

end

357

end

358

end

358

end

359

360

# Returns an array of attribute keys that are versioned. See non_versioned_columns

360

# Returns an array of attribute keys that are versioned. See non_versioned_columns

361

def versioned_attributes

361

def versioned_attributes

362

self.attributes.keys.select { |k| !self.class.non_versioned_columns.include?(k) }

362

self.attributes.keys.select { |k| !self.class.non_versioned_columns.include?(k) }

363

end

363

end

364

365

# If called with no parameters, gets whether the current model has changed and needs to be versioned.

365

# If called with no parameters, gets whether the current model has changed and needs to be versioned.

366

# If called with a single parameter, gets whether the parameter has changed.

366

# If called with a single parameter, gets whether the parameter has changed.

367

def changed?(attr_name = nil)

367

def changed?(attr_name = nil)

368

attr_name.nil? ?

368

attr_name.nil? ?

369

(!self.class.track_altered_attributes || (altered_attributes && altered_attributes.length > 0)) :

369

(!self.class.track_altered_attributes || (altered_attributes && altered_attributes.length > 0)) :

370

(altered_attributes && altered_attributes.include?(attr_name.to_s))

370

(altered_attributes && altered_attributes.include?(attr_name.to_s))

371

end

371

end

372

373

# keep old dirty? method

373

# keep old dirty? method

374

alias_method :dirty?, :changed?

374

alias_method :dirty?, :changed?

375

376

# Clones a model. Used when saving a new version or reverting a model's version.

376

# Clones a model. Used when saving a new version or reverting a model's version.

377

def clone_versioned_model(orig_model, new_model)

377

def clone_versioned_model(orig_model, new_model)

378

self.versioned_attributes.each do |key|

378

self.versioned_attributes.each do |key|

379

new_model.send("#{key}=", orig_model.send(key)) if orig_model.respond_to?(key)

379

new_model.send("#{key}=", orig_model.send(key)) if orig_model.respond_to?(key)

380

end

380

end

381

382

if self.class.columns_hash.include?(self.class.inheritance_column)

382

if self.class.columns_hash.include?(self.class.inheritance_column)

383

if orig_model.is_a?(self.class.versioned_class)

383

if orig_model.is_a?(self.class.versioned_class)

384

new_model[new_model.class.inheritance_column] = orig_model[self.class.versioned_inheritance_column]

384

new_model[new_model.class.inheritance_column] = orig_model[self.class.versioned_inheritance_column]

385

elsif new_model.is_a?(self.class.versioned_class)

385

elsif new_model.is_a?(self.class.versioned_class)

386

new_model[self.class.versioned_inheritance_column] = orig_model[orig_model.class.inheritance_column]

386

new_model[self.class.versioned_inheritance_column] = orig_model[orig_model.class.inheritance_column]

387

end

387

end

388

end

388

end

389

end

389

end

390

391

# Checks whether a new version shall be saved or not. Calls <tt>version_condition_met?</tt> and <tt>changed?</tt>.

391

# Checks whether a new version shall be saved or not. Calls <tt>version_condition_met?</tt> and <tt>changed?</tt>.

392

def save_version?

392

def save_version?

393

version_condition_met? && changed?

393

version_condition_met? && changed?

394

end

394

end

395

396

# Checks condition set in the :if option to check whether a revision should be created or not. Override this for

396

# Checks condition set in the :if option to check whether a revision should be created or not. Override this for

397

# custom version condition checking.

397

# custom version condition checking.

398

def version_condition_met?

398

def version_condition_met?

399

case

399

case

400

when version_condition.is_a?(Symbol)

400

when version_condition.is_a?(Symbol)

401

send(version_condition)

401

send(version_condition)

402

when version_condition.respond_to?(:call) && (version_condition.arity == 1 || version_condition.arity == -1)

402

when version_condition.respond_to?(:call) && (version_condition.arity == 1 || version_condition.arity == -1)

403

version_condition.call(self)

403

version_condition.call(self)

404

else

404

else

405

version_condition

405

version_condition

406

end

406

end

407

end

407

end

408

409

# Executes the block with the versioning callbacks disabled.

409

# Executes the block with the versioning callbacks disabled.

410

#

410

#

411

# @foo.without_revision do

411

# @foo.without_revision do

412

# @foo.save

412

# @foo.save

413

# end

413

# end

414

#

414

#

415

def without_revision(&block)

415

def without_revision(&block)

416

self.class.without_revision(&block)

416

self.class.without_revision(&block)

417

end

417

end

418

419

# Turns off optimistic locking for the duration of the block

419

# Turns off optimistic locking for the duration of the block

420

#

420

#

421

# @foo.without_locking do

421

# @foo.without_locking do

422

# @foo.save

422

# @foo.save

423

# end

423

# end

424

#

424

#

425

def without_locking(&block)

425

def without_locking(&block)

426

self.class.without_locking(&block)

426

self.class.without_locking(&block)

427

end

427

end

428

429

def empty_callback() end #:nodoc:

429

def empty_callback() end #:nodoc:

430

431

protected

431

protected

432

# sets the new version before saving, unless you're using optimistic locking. In that case, let it take care of the version.

432

# sets the new version before saving, unless you're using optimistic locking. In that case, let it take care of the version.

433

def set_new_version

433

def set_new_version

434

self.send("#{self.class.version_column}=", self.next_version) if new_record? || (!locking_enabled? && save_version?)

434

self.send("#{self.class.version_column}=", self.next_version) if new_record? || (!locking_enabled? && save_version?)

435

end

435

end

436

437

# Gets the next available version for the current record, or 1 for a new record

437

# Gets the next available version for the current record, or 1 for a new record

438

def next_version

438

def next_version

439

return 1 if new_record?

439

return 1 if new_record?

440

(versions.maximum('version') || 0) + 1

440

(versions.maximum('version') || 0) + 1

441

end

441

end

442

443

# clears current changed attributes. Called after save.

443

# clears current changed attributes. Called after save.

444

def clear_altered_attributes

444

def clear_altered_attributes

445

self.altered_attributes = []

445

self.altered_attributes = []

446

end

446

end

447

448

def write_changed_attribute(attr_name, attr_value)

448

def write_changed_attribute(attr_name, attr_value)

449

# Convert to db type for comparison. Avoids failing Float<=>String comparisons.

449

# Convert to db type for comparison. Avoids failing Float<=>String comparisons.

450

attr_value_for_db = self.class.columns_hash[attr_name.to_s].type_cast_from_database(attr_value)

450

attr_value_for_db = self.class.columns_hash[attr_name.to_s].type_cast_from_database(attr_value)

451

(self.altered_attributes ||= []) << attr_name.to_s unless self.changed?(attr_name) || self.send(attr_name) == attr_value_for_db

451

(self.altered_attributes ||= []) << attr_name.to_s unless self.changed?(attr_name) || self.send(attr_name) == attr_value_for_db

452

write_attribute(attr_name, attr_value_for_db)

452

write_attribute(attr_name, attr_value_for_db)

453

end

453

end

454

455

module ClassMethods

455

module ClassMethods

456

# Finds a specific version of a specific row of this model

456

# Finds a specific version of a specific row of this model

457

def find_version(id, version = nil)

457

def find_version(id, version = nil)

458

return find(id) unless version

458

return find(id) unless version

459

460

conditions = ["#{versioned_foreign_key} = ? AND version = ?", id, version]

460

conditions = ["#{versioned_foreign_key} = ? AND version = ?", id, version]

461

options = { :conditions => conditions, :limit => 1 }

461

options = { :conditions => conditions, :limit => 1 }

462

463

if result = find_versions(id, options).first

463

if result = find_versions(id, options).first

464

result

464

result

465

else

465

else

466

raise RecordNotFound, "Couldn't find #{name} with ID=#{id} and VERSION=#{version}"

466

raise RecordNotFound, "Couldn't find #{name} with ID=#{id} and VERSION=#{version}"

467

end

467

end

468

end

468

end

469

470

# Finds versions of a specific model. Takes an options hash like <tt>find</tt>

470

# Finds versions of a specific model. Takes an options hash like <tt>find</tt>

471

def find_versions(id, options = {})

471

def find_versions(id, options = {})

472

versioned_class.~~all~~({

472

versioned_class.

473

:conditions => ["#{~~vers~~i~~one~~d~~_foreign_key~~} ~~= ?"~~, id],

473

where(options[:conditions] || {versioned_foreign_key => id}).

474

:order => 'version' }.merge(options))

474

limit(options[:limit]).

475

order('version')

475

end

476

end

476

477

# Returns an array of columns that are versioned. See non_versioned_columns

478

# Returns an array of columns that are versioned. See non_versioned_columns

478

def versioned_columns

479

def versioned_columns

479

self.columns.select { |c| !non_versioned_columns.include?(c.name) }

480

self.columns.select { |c| !non_versioned_columns.include?(c.name) }

480

end

481

end

481

482

# Returns an instance of the dynamic versioned model

483

# Returns an instance of the dynamic versioned model

483

def versioned_class

484

def versioned_class

484

const_get versioned_class_name

485

const_get versioned_class_name

485

end

486

end

486

487

# Rake migration task to create the versioned table using options passed to acts_as_versioned

488

# Rake migration task to create the versioned table using options passed to acts_as_versioned

488

def create_versioned_table(create_table_options = {})

489

def create_versioned_table(create_table_options = {})

489

# create version column in main table if it does not exist

490

# create version column in main table if it does not exist

490

if !self.content_columns.find { |c| %w(version lock_version).include? c.name }

491

if !self.content_columns.find { |c| %w(version lock_version).include? c.name }

491

self.connection.add_column table_name, :version, :integer

492

self.connection.add_column table_name, :version, :integer

492

end

493

end

493

494

self.connection.create_table(versioned_table_name, create_table_options) do |t|

495

self.connection.create_table(versioned_table_name, create_table_options) do |t|

495

t.column versioned_foreign_key, :integer

496

t.column versioned_foreign_key, :integer

496

t.column :version, :integer

497

t.column :version, :integer

497

end

498

end

498

499

updated_col = nil

500

updated_col = nil

500

self.versioned_columns.each do |col|

501

self.versioned_columns.each do |col|

501

updated_col = col if !updated_col && %(updated_at updated_on).include?(col.name)

502

updated_col = col if !updated_col && %(updated_at updated_on).include?(col.name)

502

self.connection.add_column versioned_table_name, col.name, col.type,

503

self.connection.add_column versioned_table_name, col.name, col.type,

503

:limit => col.limit,

504

:limit => col.limit,

504

:default => col.default,

505

:default => col.default,

505

:scale => col.scale,

506

:scale => col.scale,

506

:precision => col.precision

507

:precision => col.precision

507

end

508

end

508

509

if type_col = self.columns_hash[inheritance_column]

510

if type_col = self.columns_hash[inheritance_column]

510

self.connection.add_column versioned_table_name, versioned_inheritance_column, type_col.type,

511

self.connection.add_column versioned_table_name, versioned_inheritance_column, type_col.type,

511

:limit => type_col.limit,

512

:limit => type_col.limit,

512

:default => type_col.default,

513

:default => type_col.default,

513

:scale => type_col.scale,

514

:scale => type_col.scale,

514

:precision => type_col.precision

515

:precision => type_col.precision

515

end

516

end

516

517

if updated_col.nil?

518

if updated_col.nil?

518

self.connection.add_column versioned_table_name, :updated_at, :timestamp

519

self.connection.add_column versioned_table_name, :updated_at, :timestamp

519

end

520

end

520

end

521

end

521

522

# Rake migration task to drop the versioned table

523

# Rake migration task to drop the versioned table

523

def drop_versioned_table

524

def drop_versioned_table

524

self.connection.drop_table versioned_table_name

525

self.connection.drop_table versioned_table_name

525

end

526

end

526

527

# Executes the block with the versioning callbacks disabled.

528

# Executes the block with the versioning callbacks disabled.

528

#

529

#

529

# Foo.without_revision do

530

# Foo.without_revision do

530

# @foo.save

531

# @foo.save

531

# end

532

# end

532

#

533

#

533

def without_revision(&block)

534

def without_revision(&block)

534

class_eval do

535

class_eval do

535

CALLBACKS.each do |attr_name|

536

CALLBACKS.each do |attr_name|

536

alias_method "orig_#{attr_name}".to_sym, attr_name

537

alias_method "orig_#{attr_name}".to_sym, attr_name

537

alias_method attr_name, :empty_callback

538

alias_method attr_name, :empty_callback

538

end

539

end

539

end

540

end

540

block.call

541

block.call

541

ensure

542

ensure

542

class_eval do

543

class_eval do

543

CALLBACKS.each do |attr_name|

544

CALLBACKS.each do |attr_name|

544

alias_method attr_name, "orig_#{attr_name}".to_sym

545

alias_method attr_name, "orig_#{attr_name}".to_sym

545

end

546

end

546

end

547

end

547

end

548

end

548

549

# Turns off optimistic locking for the duration of the block

550

# Turns off optimistic locking for the duration of the block

550

#

551

#

551

# Foo.without_locking do

552

# Foo.without_locking do

552

# @foo.save

553

# @foo.save

553

# end

554

# end

554

#

555

#

555

def without_locking(&block)

556

def without_locking(&block)

556

current = ActiveRecord::Base.lock_optimistically

557

current = ActiveRecord::Base.lock_optimistically

557

ActiveRecord::Base.lock_optimistically = false if current

558

ActiveRecord::Base.lock_optimistically = false if current

558

result = block.call

559

result = block.call

559

ActiveRecord::Base.lock_optimistically = true if current

560

ActiveRecord::Base.lock_optimistically = true if current

560

result

561

result

561

end

562

end

562

end

563

end

563

end

564

end

564

end

565

end

565

end

566

end

566

end

567

end

567

568

ActiveRecord::Base.send :include, ActiveRecord::Acts::Versioned No newline at end of file

569

ActiveRecord::Base.send :include, ActiveRecord::Acts::Versioned

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             # Copyright (c) 2005 Rick Olson
             #
             # Permission is hereby granted, free of charge, to any person obtaining
             # a copy of this software and associated documentation files (the
             # "Software"), to deal in the Software without restriction, including
             # without limitation the rights to use, copy, modify, merge, publish,
             # distribute, sublicense, and/or sell copies of the Software, and to
             # permit persons to whom the Software is furnished to do so, subject to
             # the following conditions:
             #
             # The above copyright notice and this permission notice shall be
             # included in all copies or substantial portions of the Software.
             #
             # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
             # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
             # MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
             # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
             # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
             # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
             # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
             module ActiveRecord #:nodoc:
               module Acts #:nodoc:
                 # Specify this act if you want to save a copy of the row in a versioned table.  This assumes there is a
                 # versioned table ready and that your model has a version field.  This works with optimistic locking if the lock_version
                 # column is present as well.
                 #
                 # The class for the versioned model is derived the first time it is seen. Therefore, if you change your database schema you have to restart
                 # your container for the changes to be reflected. In development mode this usually means restarting WEBrick.
                 #
                 #   class Page < ActiveRecord::Base
                 #     # assumes pages_versions table
                 #     acts_as_versioned
                 #   end
                 #
                 # Example:
                 #
                 #   page = Page.create(:title => 'hello world!')
                 #   page.version       # => 1
                 #
                 #   page.title = 'hello world'
                 #   page.save
                 #   page.version       # => 2
                 #   page.versions.size # => 2
                 #
                 #   page.revert_to(1)  # using version number
                 #   page.title         # => 'hello world!'
                 #
                 #   page.revert_to(page.versions.last) # using versioned instance
                 #   page.title         # => 'hello world'
                 #
                 #   page.versions.earliest # efficient query to find the first version
                 #   page.versions.latest   # efficient query to find the most recently created version
                 #
                 #
                 # Simple Queries to page between versions
                 #
                 #   page.versions.before(version)
                 #   page.versions.after(version)
                 #
                 # Access the previous/next versions from the versioned model itself
                 #
                 #   version = page.versions.latest
                 #   version.previous # go back one version
                 #   version.next     # go forward one version
                 #
                 # See ActiveRecord::Acts::Versioned::ClassMethods#acts_as_versioned for configuration options
                 module Versioned
                   CALLBACKS = [:set_new_version, :save_version_on_create, :save_version?, :clear_altered_attributes]
                   def self.included(base) # :nodoc:
                     base.extend ClassMethods
                   end
                   module ClassMethods
                     # == Configuration options
                     #
                     # * <tt>class_name</tt> - versioned model class name (default: PageVersion in the above example)
                     # * <tt>table_name</tt> - versioned model table name (default: page_versions in the above example)
                     # * <tt>foreign_key</tt> - foreign key used to relate the versioned model to the original model (default: page_id in the above example)
                     # * <tt>inheritance_column</tt> - name of the column to save the model's inheritance_column value for STI.  (default: versioned_type)
                     # * <tt>version_column</tt> - name of the column in the model that keeps the version number (default: version)
                     # * <tt>sequence_name</tt> - name of the custom sequence to be used by the versioned model.
                     # * <tt>limit</tt> - number of revisions to keep, defaults to unlimited
                     # * <tt>if</tt> - symbol of method to check before saving a new version.  If this method returns false, a new version is not saved.
                     #   For finer control, pass either a Proc or modify Model#version_condition_met?
                     #
                     #     acts_as_versioned :if => Proc.new { |auction| !auction.expired? }
                     #
                     #   or...
                     #
                     #     class Auction
                     #       def version_condition_met? # totally bypasses the <tt>:if</tt> option
                     #         !expired?
                     #       end
                     #     end
                     #
                     # * <tt>if_changed</tt> - Simple way of specifying attributes that are required to be changed before saving a model.  This takes
                     #   either a symbol or array of symbols.  WARNING - This will attempt to overwrite any attribute setters you may have.
                     #   Use this instead if you want to write your own attribute setters (and ignore if_changed):
                     #
                     #     def name=(new_name)
                     #       write_changed_attribute :name, new_name
                     #     end
                     #
                     # * <tt>extend</tt> - Lets you specify a module to be mixed in both the original and versioned models.  You can also just pass a block
                     #   to create an anonymous mixin:
                     #
                     #     class Auction
                     #       acts_as_versioned do
                     #         def started?
                     #           !started_at.nil?
                     #         end
                     #       end
                     #     end
                     #
                     #   or...
                     #
                     #     module AuctionExtension
                     #       def started?
                     #         !started_at.nil?
                     #       end
                     #     end
                     #     class Auction
                     #       acts_as_versioned :extend => AuctionExtension
                     #     end
                     #
                     #  Example code:
                     #
                     #    @auction = Auction.find(1)
                     #    @auction.started?
                     #    @auction.versions.first.started?
                     #
                     # == Database Schema
                     #
                     # The model that you're versioning needs to have a 'version' attribute. The model is versioned
                     # into a table called #{model}_versions where the model name is singlular. The _versions table should
                     # contain all the fields you want versioned, the same version column, and a #{model}_id foreign key field.
                     #
                     # A lock_version field is also accepted if your model uses Optimistic Locking.  If your table uses Single Table inheritance,
                     # then that field is reflected in the versioned model as 'versioned_type' by default.
                     #
                     # Acts_as_versioned comes prepared with the ActiveRecord::Acts::Versioned::ActMethods::ClassMethods#create_versioned_table
                     # method, perfect for a migration.  It will also create the version column if the main model does not already have it.
                     #
                     #   class AddVersions < ActiveRecord::Migration
                     #     def self.up
                     #       # create_versioned_table takes the same options hash
                     #       # that create_table does
                     #       Post.create_versioned_table
                     #     end
                     #
                     #     def self.down
                     #       Post.drop_versioned_table
                     #     end
                     #   end
                     #
                     # == Changing What Fields Are Versioned
                     #
                     # By default, acts_as_versioned will version all but these fields:
                     #
                     #   [self.primary_key, inheritance_column, 'version', 'lock_version', versioned_inheritance_column]
                     #
                     # You can add or change those by modifying #non_versioned_columns.  Note that this takes strings and not symbols.
                     #
                     #   class Post < ActiveRecord::Base
                     #     acts_as_versioned
                     #     self.non_versioned_columns << 'comments_count'
                     #   end
                     #
                     def acts_as_versioned(options = {}, &extension)
                       # don't allow multiple calls
                       return if self.included_modules.include?(ActiveRecord::Acts::Versioned::ActMethods)
                       send :include, ActiveRecord::Acts::Versioned::ActMethods
                       cattr_accessor :versioned_class_name, :versioned_foreign_key, :versioned_table_name, :versioned_inheritance_column,
                         :version_column, :max_version_limit, :track_altered_attributes, :version_condition, :version_sequence_name, :non_versioned_columns,
                         :version_association_options
                       # legacy
                       alias_method :non_versioned_fields,  :non_versioned_columns
                       alias_method :non_versioned_fields=, :non_versioned_columns=
                       class << self
                         alias_method :non_versioned_fields,  :non_versioned_columns
                         alias_method :non_versioned_fields=, :non_versioned_columns=
                       end
                       send :attr_accessor, :altered_attributes
                       self.versioned_class_name         = options[:class_name]  || "Version"
                       self.versioned_foreign_key        = options[:foreign_key] || self.to_s.foreign_key
                       self.versioned_table_name         = options[:table_name]  || "#{table_name_prefix}#{base_class.name.demodulize.underscore}_versions#{table_name_suffix}"
                       self.versioned_inheritance_column = options[:inheritance_column] || "versioned_#{inheritance_column}"
                       self.version_column               = options[:version_column]     || 'version'
                       self.version_sequence_name        = options[:sequence_name]
                       self.max_version_limit            = options[:limit].to_i
                       self.version_condition            = options[:if] || true
                       self.non_versioned_columns        = [self.primary_key, inheritance_column, 'version', 'lock_version', versioned_inheritance_column]
                       self.version_association_options  = {
                                                             :class_name  => "#{self.to_s}::#{versioned_class_name}",
                                                             :foreign_key => versioned_foreign_key,
                                                             :dependent   => :delete_all
                                                           }.merge(options[:association_options] || {})
                       if block_given?
                         extension_module_name = "#{versioned_class_name}Extension"
                         silence_warnings do
                           self.const_set(extension_module_name, Module.new(&extension))
                         end
                         options[:extend] = self.const_get(extension_module_name)
                       end
                       class_eval do
                         has_many :versions, version_association_options do
                           # finds earliest version of this record
                           def earliest
                             @earliest ||= order('version').first
                           end
                           # find latest version of this record
                           def latest
                             @latest ||= order('version desc').first
                           end
                         end
                         before_save  :set_new_version
                         after_create :save_version_on_create
                         after_update :save_version
                         after_save   :clear_old_versions
                         after_save   :clear_altered_attributes
                         unless options[:if_changed].nil?
                           self.track_altered_attributes = true
                           options[:if_changed] = [options[:if_changed]] unless options[:if_changed].is_a?(Array)
                           options[:if_changed].each do |attr_name|
                             define_method("#{attr_name}=") do |value|
                               write_changed_attribute attr_name, value
                             end
                           end
                         end
                         include options[:extend] if options[:extend].is_a?(Module)
                       end
                       # create the dynamic versioned model
                       const_set(versioned_class_name, Class.new(ActiveRecord::Base)).class_eval do
                         def self.reloadable? ; false ; end
                         # find first version before the given version
                         def self.before(version)
                           order('version desc').
                             where("#{original_class.versioned_foreign_key} = ? and version < ?", version.send(original_class.versioned_foreign_key), version.version).
                             first
                         end
                         # find first version after the given version.
                         def self.after(version)
                           order('version').
                             where("#{original_class.versioned_foreign_key} = ? and version > ?", version.send(original_class.versioned_foreign_key), version.version).
                             first
                         end
                         def previous
                           self.class.before(self)
                         end
                         def next
                           self.class.after(self)
                         end
                         def versions_count
                           page.version
                         end
                       end
                       versioned_class.cattr_accessor :original_class
                       versioned_class.original_class = self
                       versioned_class.table_name = versioned_table_name
                       versioned_class.belongs_to self.to_s.demodulize.underscore.to_sym,
                         :class_name  => "::#{self.to_s}",
                         :foreign_key => versioned_foreign_key
                       versioned_class.send :include, options[:extend]         if options[:extend].is_a?(Module)
                       versioned_class.set_sequence_name version_sequence_name if version_sequence_name
                     end
                   end
                   module ActMethods
                     def self.included(base) # :nodoc:
                       base.extend ClassMethods
                     end
                     # Finds a specific version of this record
                     def find_version(version = nil)
                       self.class.find_version(id, version)
                     end
                     # Saves a version of the model if applicable
                     def save_version
                       save_version_on_create if save_version?
                     end
                     # Saves a version of the model in the versioned table.  This is called in the after_save callback by default
                     def save_version_on_create
                       rev = self.class.versioned_class.new
                       self.clone_versioned_model(self, rev)
                       rev.version = send(self.class.version_column)
                       rev.send("#{self.class.versioned_foreign_key}=", self.id)
                       rev.save
                     end
                     # Clears old revisions if a limit is set with the :limit option in <tt>acts_as_versioned</tt>.
                     # Override this method to set your own criteria for clearing old versions.
                     def clear_old_versions
                       return if self.class.max_version_limit == 0
                       excess_baggage = send(self.class.version_column).to_i - self.class.max_version_limit
                       if excess_baggage > 0
                         sql = "DELETE FROM #{self.class.versioned_table_name} WHERE version <= #{excess_baggage} AND #{self.class.versioned_foreign_key} = #{self.id}"
                         self.class.versioned_class.connection.execute sql
                       end
                     end
                     def versions_count
                       version
                     end
                     # Reverts a model to a given version.  Takes either a version number or an instance of the versioned model
                     def revert_to(version)
                       if version.is_a?(self.class.versioned_class)
                         return false unless version.send(self.class.versioned_foreign_key) == self.id and !version.new_record?
                       else
                         return false unless version = versions.find_by_version(version)
                       end
                       self.clone_versioned_model(version, self)
                       self.send("#{self.class.version_column}=", version.version)
                       true
                     end
                     # Reverts a model to a given version and saves the model.
                     # Takes either a version number or an instance of the versioned model
                     def revert_to!(version)
                       revert_to(version) ? save_without_revision : false
                     end
                     # Temporarily turns off Optimistic Locking while saving.  Used when reverting so that a new version is not created.
                     def save_without_revision
                       save_without_revision!
                       true
                     rescue
                       false
                     end
                     def save_without_revision!
                       without_locking do
                         without_revision do
                           save!
                         end
                       end
                     end
                     # Returns an array of attribute keys that are versioned.  See non_versioned_columns
                     def versioned_attributes
                       self.attributes.keys.select { |k| !self.class.non_versioned_columns.include?(k) }
                     end
                     # If called with no parameters, gets whether the current model has changed and needs to be versioned.
                     # If called with a single parameter, gets whether the parameter has changed.
                     def changed?(attr_name = nil)
                       attr_name.nil? ?
                         (!self.class.track_altered_attributes || (altered_attributes && altered_attributes.length > 0)) :
                         (altered_attributes && altered_attributes.include?(attr_name.to_s))
                     end
                     # keep old dirty? method
                     alias_method :dirty?, :changed?
                     # Clones a model.  Used when saving a new version or reverting a model's version.
                     def clone_versioned_model(orig_model, new_model)
                       self.versioned_attributes.each do |key|
                         new_model.send("#{key}=", orig_model.send(key)) if orig_model.respond_to?(key)
                       end
                       if self.class.columns_hash.include?(self.class.inheritance_column)
                         if orig_model.is_a?(self.class.versioned_class)
                           new_model[new_model.class.inheritance_column] = orig_model[self.class.versioned_inheritance_column]
                         elsif new_model.is_a?(self.class.versioned_class)
                           new_model[self.class.versioned_inheritance_column] = orig_model[orig_model.class.inheritance_column]
                         end
                       end
                     end
                     # Checks whether a new version shall be saved or not.  Calls <tt>version_condition_met?</tt> and <tt>changed?</tt>.
                     def save_version?
                       version_condition_met? && changed?
                     end
                     # Checks condition set in the :if option to check whether a revision should be created or not.  Override this for
                     # custom version condition checking.
                     def version_condition_met?
                       case
                       when version_condition.is_a?(Symbol)
                         send(version_condition)
                       when version_condition.respond_to?(:call) && (version_condition.arity == 1 || version_condition.arity == -1)
                         version_condition.call(self)
                       else
                         version_condition
                       end
                     end
                     # Executes the block with the versioning callbacks disabled.
                     #
                     #   @foo.without_revision do
                     #     @foo.save
                     #   end
                     #
                     def without_revision(&block)
                       self.class.without_revision(&block)
                     end
                     # Turns off optimistic locking for the duration of the block
                     #
                     #   @foo.without_locking do
                     #     @foo.save
                     #   end
                     #
                     def without_locking(&block)
                       self.class.without_locking(&block)
                     end
                     def empty_callback() end #:nodoc:
                     protected
                       # sets the new version before saving, unless you're using optimistic locking.  In that case, let it take care of the version.
                       def set_new_version
                         self.send("#{self.class.version_column}=", self.next_version) if new_record? || (!locking_enabled? && save_version?)
                       end
                       # Gets the next available version for the current record, or 1 for a new record
                       def next_version
                         return 1 if new_record?
                         (versions.maximum('version') || 0) + 1
                       end
                       # clears current changed attributes.  Called after save.
                       def clear_altered_attributes
                         self.altered_attributes = []
                       end
                       def write_changed_attribute(attr_name, attr_value)
                         # Convert to db type for comparison. Avoids failing Float<=>String comparisons.
                         attr_value_for_db = self.class.columns_hash[attr_name.to_s].type_cast_from_database(attr_value)
                         (self.altered_attributes ||= []) << attr_name.to_s unless self.changed?(attr_name) || self.send(attr_name) == attr_value_for_db
                         write_attribute(attr_name, attr_value_for_db)
                       end
                     module ClassMethods
                       # Finds a specific version of a specific row of this model
                       def find_version(id, version = nil)
                         return find(id) unless version
                         conditions = ["#{versioned_foreign_key} = ? AND version = ?", id, version]
                         options = { :conditions => conditions, :limit => 1 }
                         if result = find_versions(id, options).first
                           result
                         else
                           raise RecordNotFound, "Couldn't find #{name} with ID=#{id} and VERSION=#{version}"
                         end
                       end
                       # Finds versions of a specific model.  Takes an options hash like <tt>find</tt>
                       def find_versions(id, options = {})
-                        versioned_class.all({
+                        versioned_class.
-                          :conditions => ["#{versioned_foreign_key} = ?", id],
+                            where(options[:conditions] || {versioned_foreign_key => id}).
-                          :order      => 'version' }.merge(options))
+                            limit(options[:limit]).
+                            order('version')
                       end
                       # Returns an array of columns that are versioned.  See non_versioned_columns
                       def versioned_columns
                         self.columns.select { |c| !non_versioned_columns.include?(c.name) }
                       end
                       # Returns an instance of the dynamic versioned model
                       def versioned_class
                         const_get versioned_class_name
                       end
                       # Rake migration task to create the versioned table using options passed to acts_as_versioned
                       def create_versioned_table(create_table_options = {})
                         # create version column in main table if it does not exist
                         if !self.content_columns.find { |c| %w(version lock_version).include? c.name }
                           self.connection.add_column table_name, :version, :integer
                         end
                         self.connection.create_table(versioned_table_name, create_table_options) do |t|
                           t.column versioned_foreign_key, :integer
                           t.column :version, :integer
                         end
                         updated_col = nil
                         self.versioned_columns.each do |col|
                           updated_col = col if !updated_col && %(updated_at updated_on).include?(col.name)
                           self.connection.add_column versioned_table_name, col.name, col.type,
                             :limit => col.limit,
                             :default => col.default,
                             :scale => col.scale,
                             :precision => col.precision
                         end
                         if type_col = self.columns_hash[inheritance_column]
                           self.connection.add_column versioned_table_name, versioned_inheritance_column, type_col.type,
                             :limit => type_col.limit,
                             :default => type_col.default,
                             :scale => type_col.scale,
                             :precision => type_col.precision
                         end
                         if updated_col.nil?
                           self.connection.add_column versioned_table_name, :updated_at, :timestamp
                         end
                       end
                       # Rake migration task to drop the versioned table
                       def drop_versioned_table
                         self.connection.drop_table versioned_table_name
                       end
                       # Executes the block with the versioning callbacks disabled.
                       #
                       #   Foo.without_revision do
                       #     @foo.save
                       #   end
                       #
                       def without_revision(&block)
                         class_eval do
                           CALLBACKS.each do |attr_name|
                             alias_method "orig_#{attr_name}".to_sym, attr_name
                             alias_method attr_name, :empty_callback
                           end
                         end
                         block.call
                       ensure
                         class_eval do
                           CALLBACKS.each do |attr_name|
                             alias_method attr_name, "orig_#{attr_name}".to_sym
                           end
                         end
                       end
                       # Turns off optimistic locking for the duration of the block
                       #
                       #   Foo.without_locking do
                       #     @foo.save
                       #   end
                       #
                       def without_locking(&block)
                         current = ActiveRecord::Base.lock_optimistically
                         ActiveRecord::Base.lock_optimistically = false if current
                         result = block.call
                         ActiveRecord::Base.lock_optimistically = true if current
                         result
                       end
                     end
                   end
                 end
               end
             end
             ActiveRecord::Base.send :include, ActiveRecord::Acts::Versioned