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@@ -1,62 +1,67 @@
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-Cached Values
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-==============
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+= Cached Values
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-* http://github.com/JackDanger/cached_values_gem/
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+* http://github.com/JackDanger/cached_values/
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-A dead-simple way to calculate any value via Ruby or SQL and  have it saved in a database field.
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+A dead-simple way to calculate any value via Ruby or SQL and (optionally) have it saved in a database field.
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-Example
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-=======
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+== REQUIREMENTS:
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-USAGE:
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+* ObjectProxy
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+== INSTALL:
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+
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+* as gem: sudo gem install cached_values
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+* as plugin: ./script/plugin install git://github.com/JackDanger/cached_values.git
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+
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+== USAGE:
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+
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 You can calculate values with a single line in any ActiveRecord model.  To actually save those values you'll need to create
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 an attribute in your schema.  By default the cached_value instance will look for an attribute with the same name as itself.
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 You can override this by specifying a :cache => :some_attribute option
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 A very simple case in which cached_values works just like the .count method on a has_many association:
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-  class Company < ActiveRecord::Base
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-   caches_value :total_employees, :sql => 'select count(*) from employees where company_id = #{id}'
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+  class Leprechaun < ActiveRecord::Base
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+   caches_value :total_gold_coins, :sql => 'select count(*) from gold_coins where leprechaun_id = #{id}'
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   end
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+  
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+  Company.find(4).total_employees # => 45
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 A more sophisticated example:
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-  class User < ActiveRecord::Base
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-   has_many :trinkets
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-   has_many :sales, :through => :trinkets
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-   caches_value :remaining_trinket_sales_allotted, :sql => '... very complicated sql here ...'
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+  class Leprechaun < ActiveRecord::Base
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+   has_many :lucky_charms
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+   has_many :deceived_children, :through => :lucky_charms
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+   caches_value :total_children_remaining_to_be_deceived, :sql => '... very complicated sql here ...'
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   end
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-
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-reload() clears the cache and recalculates the value:
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-
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-  user = User.find(:first)
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-  user.remaining_trinket_sales_allotted # => 70
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-  Trinket.delete_all # <= any operation that would affect our value
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-  user.remaining_trinket_sales_allotted # => 70
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-  user.remaining_trinket_sales_allotted.reload # => 113
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-The same effect could be had by calling clear() which clears the cache and removes the cache instance from memory
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+  Leprechaun.find(14).total_children_remaining_to_be_deceived # => 6,692,243,122
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+The values can be of any type.  The plugin will attempt to cast SQL results to the type corresponding with their database cache
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+but calculations in Ruby are left alone.
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+
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 You can also calculate the value in Ruby using a string to be eval'ed or a Proc.  Both are evaluated
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 in the context of the record instance.
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-  caches_value :expensive_calculation, :eval => "some_big_expensize_calculation(self.id)"
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-  caches_value :other_expensive_process, :eval => Proc.new {|record| record.other_expensize_process }
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+  class Leprechaun < ActiveRecord::Base
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+    caches_value :total_gold, :eval => "some_archaic_and_silly_calculation(self.gold_coins)"
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+    caches_value :total_lucky_charms, :eval => Proc.new {|record| record.calculate_total_lucky_charms }
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+  end
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 The cache is customizable, you can specify which attribute should be used as a cache:
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-  caches_value :full_formula, :sql => '...'                         # uses 'full_formula' column if it exists
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-  caches_value :standard_deviation, :sql => '...', :cache => 'std'  # uses 'std' column if it exists
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-  caches_value :id, , :sql => '...', :cache => false                # does NOT save any cache.  This avoids overwriting an attribute
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+  caches_value :runic_formula, :sql => '...'          # uses 'full_formula' column if it exists
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+  caches_value :standard_deviation_of_gold_over_time, # uses 'std' column if it exists
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+               :sql => '...', :cache => 'std'
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+  caches_value :id, :sql => '...', :cache => false    # does NOT save any cache.  This avoids overwriting an attribute
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-Callbacks can be used to call load(), clear(), or reload() at certain times:
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+ActiveRecord callbacks can be used to call load (make sure the value is in memory), clear (flush the cache and
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+delete the instance), or reload (flush cache and reload instance) at certain times:
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   caches_value :standard_deviation, :sql => '...', :reload => [:after_save, :before_validation]
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   caches_value :full_formula, :sql => '...', :clear => :after_find
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-
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-Bugs can be filed at http://code.lighthouseapp.com/projects/4502-hoopla-rails-plugins/overview
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+Bugs can be filed at http://code.lighthouseapp.com/projects/4502-hoopla-rails-plugins/
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 Copyright (c) 2007 Jack Danger Canty @ http://6brand.com, released under the MIT license