module ActiveRecord # = Active Record Query Cache class QueryCache module ClassMethods # Enable the query cache within the block if Active Record is configured. # If it's not, it will execute the given block. def cache(&block) if ActiveRecord::Base.connected? connection.cache(&block) else yield end end # Disable the query cache within the block if Active Record is configured. # If it's not, it will execute the given block. def uncached(&block) if ActiveRecord::Base.connected? connection.uncached(&block) else yield end end end def initialize(app) @app = app end def call(env) connection = ActiveRecord::Base.connection enabled = connection.query_cache_enabled connection_id = ActiveRecord::Base.connection_id connection.enable_query_cache! response = @app.call(env) response[2] = Rack::BodyProxy.new(response[2]) do restore_query_cache_settings(connection_id, enabled) end response rescue Exception => e restore_query_cache_settings(connection_id, enabled) raise e end private def restore_query_cache_settings(connection_id, enabled) ActiveRecord::Base.connection_id = connection_id ActiveRecord::Base.connection.clear_query_cache ActiveRecord::Base.connection.disable_query_cache! unless enabled end end end