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1 module CollectiveIdea #:nodoc:
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2 module Acts #:nodoc:
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3 module NestedSet #:nodoc:
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4
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5 # This acts provides Nested Set functionality. Nested Set is a smart way to implement
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6 # an _ordered_ tree, with the added feature that you can select the children and all of their
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7 # descendants with a single query. The drawback is that insertion or move need some complex
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8 # sql queries. But everything is done here by this module!
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9 #
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10 # Nested sets are appropriate each time you want either an orderd tree (menus,
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11 # commercial categories) or an efficient way of querying big trees (threaded posts).
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12 #
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13 # == API
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14 #
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15 # Methods names are aligned with acts_as_tree as much as possible to make replacment from one
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16 # by another easier.
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17 #
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18 # item.children.create(:name => "child1")
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19 #
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20
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21 # Configuration options are:
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22 #
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23 # * +:parent_column+ - specifies the column name to use for keeping the position integer (default: parent_id)
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24 # * +:left_column+ - column name for left boundry data, default "lft"
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25 # * +:right_column+ - column name for right boundry data, default "rgt"
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26 # * +:scope+ - restricts what is to be considered a list. Given a symbol, it'll attach "_id"
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27 # (if it hasn't been already) and use that as the foreign key restriction. You
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28 # can also pass an array to scope by multiple attributes.
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29 # Example: <tt>acts_as_nested_set :scope => [:notable_id, :notable_type]</tt>
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30 # * +:dependent+ - behavior for cascading destroy. If set to :destroy, all the
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31 # child objects are destroyed alongside this object by calling their destroy
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32 # method. If set to :delete_all (default), all the child objects are deleted
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33 # without calling their destroy method.
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34 # * +:counter_cache+ adds a counter cache for the number of children.
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35 # defaults to false.
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36 # Example: <tt>acts_as_nested_set :counter_cache => :children_count</tt>
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37 #
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38 # See CollectiveIdea::Acts::NestedSet::Model::ClassMethods for a list of class methods and
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39 # CollectiveIdea::Acts::NestedSet::Model for a list of instance methods added
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40 # to acts_as_nested_set models
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41 def acts_as_nested_set(options = {})
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42 options = {
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43 :parent_column => 'parent_id',
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44 :left_column => 'lft',
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45 :right_column => 'rgt',
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46 :dependent => :delete_all, # or :destroy
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47 :counter_cache => false,
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48 :order => 'id'
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49 }.merge(options)
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50
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51 if options[:scope].is_a?(Symbol) && options[:scope].to_s !~ /_id$/
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52 options[:scope] = "#{options[:scope]}_id".intern
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53 end
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54
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55 class_attribute :acts_as_nested_set_options
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56 self.acts_as_nested_set_options = options
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57
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58 include CollectiveIdea::Acts::NestedSet::Model
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59 include Columns
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60 extend Columns
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61
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62 belongs_to :parent, :class_name => self.base_class.to_s,
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63 :foreign_key => parent_column_name,
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64 :counter_cache => options[:counter_cache],
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65 :inverse_of => :children
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66 has_many :children, :class_name => self.base_class.to_s,
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67 :foreign_key => parent_column_name, :order => left_column_name,
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68 :inverse_of => :parent,
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69 :before_add => options[:before_add],
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70 :after_add => options[:after_add],
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71 :before_remove => options[:before_remove],
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72 :after_remove => options[:after_remove]
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73
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74 attr_accessor :skip_before_destroy
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75
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76 before_create :set_default_left_and_right
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77 before_save :store_new_parent
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78 after_save :move_to_new_parent
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79 before_destroy :destroy_descendants
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80
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81 # no assignment to structure fields
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82 [left_column_name, right_column_name].each do |column|
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83 module_eval <<-"end_eval", __FILE__, __LINE__
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84 def #{column}=(x)
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85 raise ActiveRecord::ActiveRecordError, "Unauthorized assignment to #{column}: it's an internal field handled by acts_as_nested_set code, use move_to_* methods instead."
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86 end
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87 end_eval
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88 end
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89
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90 define_model_callbacks :move
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91 end
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92
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93 module Model
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94 extend ActiveSupport::Concern
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95
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96 module ClassMethods
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97 # Returns the first root
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98 def root
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99 roots.first
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100 end
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101
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102 def roots
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103 where(parent_column_name => nil).order(quoted_left_column_name)
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104 end
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105
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106 def leaves
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107 where("#{quoted_right_column_name} - #{quoted_left_column_name} = 1").order(quoted_left_column_name)
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108 end
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109
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110 def valid?
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111 left_and_rights_valid? && no_duplicates_for_columns? && all_roots_valid?
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112 end
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113
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114 def left_and_rights_valid?
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115 joins("LEFT OUTER JOIN #{quoted_table_name} AS parent ON " +
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116 "#{quoted_table_name}.#{quoted_parent_column_name} = parent.#{primary_key}").
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117 where(
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118 "#{quoted_table_name}.#{quoted_left_column_name} IS NULL OR " +
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119 "#{quoted_table_name}.#{quoted_right_column_name} IS NULL OR " +
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120 "#{quoted_table_name}.#{quoted_left_column_name} >= " +
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121 "#{quoted_table_name}.#{quoted_right_column_name} OR " +
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122 "(#{quoted_table_name}.#{quoted_parent_column_name} IS NOT NULL AND " +
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123 "(#{quoted_table_name}.#{quoted_left_column_name} <= parent.#{quoted_left_column_name} OR " +
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124 "#{quoted_table_name}.#{quoted_right_column_name} >= parent.#{quoted_right_column_name}))"
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125 ).count == 0
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126 end
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127
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128 def no_duplicates_for_columns?
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129 scope_string = Array(acts_as_nested_set_options[:scope]).map do |c|
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130 connection.quote_column_name(c)
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131 end.push(nil).join(", ")
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132 [quoted_left_column_name, quoted_right_column_name].all? do |column|
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133 # No duplicates
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134 select("#{scope_string}#{column}, COUNT(#{column})").
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135 group("#{scope_string}#{column}").
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136 having("COUNT(#{column}) > 1").
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137 first.nil?
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138 end
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139 end
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140
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141 # Wrapper for each_root_valid? that can deal with scope.
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142 def all_roots_valid?
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143 if acts_as_nested_set_options[:scope]
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144 roots.group(scope_column_names).group_by{|record| scope_column_names.collect{|col| record.send(col.to_sym)}}.all? do |scope, grouped_roots|
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145 each_root_valid?(grouped_roots)
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146 end
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147 else
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148 each_root_valid?(roots)
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149 end
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150 end
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151
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152 def each_root_valid?(roots_to_validate)
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153 left = right = 0
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154 roots_to_validate.all? do |root|
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155 (root.left > left && root.right > right).tap do
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156 left = root.left
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157 right = root.right
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158 end
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159 end
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160 end
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161
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162 # Rebuilds the left & rights if unset or invalid.
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163 # Also very useful for converting from acts_as_tree.
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164 def rebuild!(validate_nodes = true)
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165 # Don't rebuild a valid tree.
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166 return true if valid?
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167
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168 scope = lambda{|node|}
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169 if acts_as_nested_set_options[:scope]
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170 scope = lambda{|node|
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171 scope_column_names.inject(""){|str, column_name|
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172 str << "AND #{connection.quote_column_name(column_name)} = #{connection.quote(node.send(column_name.to_sym))} "
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173 }
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174 }
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175 end
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176 indices = {}
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177
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178 set_left_and_rights = lambda do |node|
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179 # set left
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180 node[left_column_name] = indices[scope.call(node)] += 1
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181 # find
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182 where(["#{quoted_parent_column_name} = ? #{scope.call(node)}", node]).order(acts_as_nested_set_options[:order]).each{|n| set_left_and_rights.call(n) }
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183 # set right
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184 node[right_column_name] = indices[scope.call(node)] += 1
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185 node.save!(:validate => validate_nodes)
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186 end
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187
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188 # Find root node(s)
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189 root_nodes = where("#{quoted_parent_column_name} IS NULL").order(acts_as_nested_set_options[:order]).each do |root_node|
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190 # setup index for this scope
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191 indices[scope.call(root_node)] ||= 0
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192 set_left_and_rights.call(root_node)
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193 end
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194 end
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195
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196 # Iterates over tree elements and determines the current level in the tree.
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197 # Only accepts default ordering, odering by an other column than lft
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198 # does not work. This method is much more efficent than calling level
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199 # because it doesn't require any additional database queries.
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200 #
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201 # Example:
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202 # Category.each_with_level(Category.root.self_and_descendants) do |o, level|
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203 #
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204 def each_with_level(objects)
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205 path = [nil]
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206 objects.each do |o|
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207 if o.parent_id != path.last
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208 # we are on a new level, did we decent or ascent?
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209 if path.include?(o.parent_id)
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210 # remove wrong wrong tailing paths elements
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211 path.pop while path.last != o.parent_id
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212 else
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213 path << o.parent_id
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214 end
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215 end
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216 yield(o, path.length - 1)
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217 end
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218 end
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219 end
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220
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221 # Any instance method that returns a collection makes use of Rails 2.1's named_scope (which is bundled for Rails 2.0), so it can be treated as a finder.
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222 #
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223 # category.self_and_descendants.count
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224 # category.ancestors.find(:all, :conditions => "name like '%foo%'")
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225
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226 # Value of the parent column
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227 def parent_id
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228 self[parent_column_name]
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229 end
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230
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231 # Value of the left column
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232 def left
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233 self[left_column_name]
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234 end
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235
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236 # Value of the right column
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237 def right
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238 self[right_column_name]
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239 end
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240
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241 # Returns true if this is a root node.
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242 def root?
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243 parent_id.nil?
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244 end
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245
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246 def leaf?
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247 new_record? || (right - left == 1)
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248 end
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249
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250 # Returns true is this is a child node
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251 def child?
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252 !parent_id.nil?
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253 end
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254
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255 # Returns root
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256 def root
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257 self_and_ancestors.where(parent_column_name => nil).first
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258 end
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259
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260 # Returns the array of all parents and self
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261 def self_and_ancestors
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262 nested_set_scope.where([
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263 "#{self.class.quoted_table_name}.#{quoted_left_column_name} <= ? AND #{self.class.quoted_table_name}.#{quoted_right_column_name} >= ?", left, right
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264 ])
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265 end
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266
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267 # Returns an array of all parents
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268 def ancestors
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269 without_self self_and_ancestors
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270 end
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271
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272 # Returns the array of all children of the parent, including self
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273 def self_and_siblings
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274 nested_set_scope.where(parent_column_name => parent_id)
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275 end
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276
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277 # Returns the array of all children of the parent, except self
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278 def siblings
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279 without_self self_and_siblings
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280 end
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281
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282 # Returns a set of all of its nested children which do not have children
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283 def leaves
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284 descendants.where("#{self.class.quoted_table_name}.#{quoted_right_column_name} - #{self.class.quoted_table_name}.#{quoted_left_column_name} = 1")
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285 end
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286
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287 # Returns the level of this object in the tree
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288 # root level is 0
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289 def level
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290 parent_id.nil? ? 0 : ancestors.count
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291 end
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292
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293 # Returns a set of itself and all of its nested children
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294 def self_and_descendants
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295 nested_set_scope.where([
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296 "#{self.class.quoted_table_name}.#{quoted_left_column_name} >= ? AND #{self.class.quoted_table_name}.#{quoted_right_column_name} <= ?", left, right
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297 ])
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298 end
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299
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300 # Returns a set of all of its children and nested children
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301 def descendants
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302 without_self self_and_descendants
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303 end
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304
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305 def is_descendant_of?(other)
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306 other.left < self.left && self.left < other.right && same_scope?(other)
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307 end
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308
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309 def is_or_is_descendant_of?(other)
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310 other.left <= self.left && self.left < other.right && same_scope?(other)
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311 end
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312
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313 def is_ancestor_of?(other)
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314 self.left < other.left && other.left < self.right && same_scope?(other)
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315 end
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316
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317 def is_or_is_ancestor_of?(other)
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318 self.left <= other.left && other.left < self.right && same_scope?(other)
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319 end
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320
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321 # Check if other model is in the same scope
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322 def same_scope?(other)
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323 Array(acts_as_nested_set_options[:scope]).all? do |attr|
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324 self.send(attr) == other.send(attr)
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325 end
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326 end
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327
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328 # Find the first sibling to the left
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329 def left_sibling
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330 siblings.where(["#{self.class.quoted_table_name}.#{quoted_left_column_name} < ?", left]).
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331 order("#{self.class.quoted_table_name}.#{quoted_left_column_name} DESC").last
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332 end
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333
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334 # Find the first sibling to the right
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335 def right_sibling
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336 siblings.where(["#{self.class.quoted_table_name}.#{quoted_left_column_name} > ?", left]).first
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337 end
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338
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339 # Shorthand method for finding the left sibling and moving to the left of it.
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Chris@1464
|
340 def move_left
|
Chris@1464
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341 move_to_left_of left_sibling
|
Chris@1464
|
342 end
|
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|
343
|
Chris@1464
|
344 # Shorthand method for finding the right sibling and moving to the right of it.
|
Chris@1464
|
345 def move_right
|
Chris@1464
|
346 move_to_right_of right_sibling
|
Chris@1464
|
347 end
|
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|
348
|
Chris@1464
|
349 # Move the node to the left of another node (you can pass id only)
|
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350 def move_to_left_of(node)
|
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|
351 move_to node, :left
|
Chris@1464
|
352 end
|
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|
353
|
Chris@1464
|
354 # Move the node to the left of another node (you can pass id only)
|
Chris@1464
|
355 def move_to_right_of(node)
|
Chris@1464
|
356 move_to node, :right
|
Chris@1464
|
357 end
|
Chris@1464
|
358
|
Chris@1464
|
359 # Move the node to the child of another node (you can pass id only)
|
Chris@1464
|
360 def move_to_child_of(node)
|
Chris@1464
|
361 move_to node, :child
|
Chris@1464
|
362 end
|
Chris@1464
|
363
|
Chris@1464
|
364 # Move the node to root nodes
|
Chris@1464
|
365 def move_to_root
|
Chris@1464
|
366 move_to nil, :root
|
Chris@1464
|
367 end
|
Chris@1464
|
368
|
Chris@1464
|
369 def move_possible?(target)
|
Chris@1464
|
370 self != target && # Can't target self
|
Chris@1464
|
371 same_scope?(target) && # can't be in different scopes
|
Chris@1464
|
372 # !(left..right).include?(target.left..target.right) # this needs tested more
|
Chris@1464
|
373 # detect impossible move
|
Chris@1464
|
374 !((left <= target.left && right >= target.left) or (left <= target.right && right >= target.right))
|
Chris@1464
|
375 end
|
Chris@1464
|
376
|
Chris@1464
|
377 def to_text
|
Chris@1464
|
378 self_and_descendants.map do |node|
|
Chris@1464
|
379 "#{'*'*(node.level+1)} #{node.id} #{node.to_s} (#{node.parent_id}, #{node.left}, #{node.right})"
|
Chris@1464
|
380 end.join("\n")
|
Chris@1464
|
381 end
|
Chris@1464
|
382
|
Chris@1464
|
383 protected
|
Chris@1464
|
384
|
Chris@1464
|
385 def without_self(scope)
|
Chris@1464
|
386 scope.where(["#{self.class.quoted_table_name}.#{self.class.primary_key} != ?", self])
|
Chris@1464
|
387 end
|
Chris@1464
|
388
|
Chris@1464
|
389 # All nested set queries should use this nested_set_scope, which performs finds on
|
Chris@1464
|
390 # the base ActiveRecord class, using the :scope declared in the acts_as_nested_set
|
Chris@1464
|
391 # declaration.
|
Chris@1464
|
392 def nested_set_scope(options = {})
|
Chris@1464
|
393 options = {:order => "#{self.class.quoted_table_name}.#{quoted_left_column_name}"}.merge(options)
|
Chris@1464
|
394 scopes = Array(acts_as_nested_set_options[:scope])
|
Chris@1464
|
395 options[:conditions] = scopes.inject({}) do |conditions,attr|
|
Chris@1464
|
396 conditions.merge attr => self[attr]
|
Chris@1464
|
397 end unless scopes.empty?
|
Chris@1464
|
398 self.class.base_class.scoped options
|
Chris@1464
|
399 end
|
Chris@1464
|
400
|
Chris@1464
|
401 def store_new_parent
|
Chris@1464
|
402 @move_to_new_parent_id = send("#{parent_column_name}_changed?") ? parent_id : false
|
Chris@1464
|
403 true # force callback to return true
|
Chris@1464
|
404 end
|
Chris@1464
|
405
|
Chris@1464
|
406 def move_to_new_parent
|
Chris@1464
|
407 if @move_to_new_parent_id.nil?
|
Chris@1464
|
408 move_to_root
|
Chris@1464
|
409 elsif @move_to_new_parent_id
|
Chris@1464
|
410 move_to_child_of(@move_to_new_parent_id)
|
Chris@1464
|
411 end
|
Chris@1464
|
412 end
|
Chris@1464
|
413
|
Chris@1464
|
414 # on creation, set automatically lft and rgt to the end of the tree
|
Chris@1464
|
415 def set_default_left_and_right
|
Chris@1464
|
416 highest_right_row = nested_set_scope(:order => "#{quoted_right_column_name} desc").limit(1).lock(true).first
|
Chris@1464
|
417 maxright = highest_right_row ? (highest_right_row[right_column_name] || 0) : 0
|
Chris@1464
|
418 # adds the new node to the right of all existing nodes
|
Chris@1464
|
419 self[left_column_name] = maxright + 1
|
Chris@1464
|
420 self[right_column_name] = maxright + 2
|
Chris@1464
|
421 end
|
Chris@1464
|
422
|
Chris@1464
|
423 def in_tenacious_transaction(&block)
|
Chris@1464
|
424 retry_count = 0
|
Chris@1464
|
425 begin
|
Chris@1464
|
426 transaction(&block)
|
Chris@1464
|
427 rescue ActiveRecord::StatementInvalid => error
|
Chris@1464
|
428 raise unless connection.open_transactions.zero?
|
Chris@1464
|
429 raise unless error.message =~ /Deadlock found when trying to get lock|Lock wait timeout exceeded/
|
Chris@1464
|
430 raise unless retry_count < 10
|
Chris@1464
|
431 retry_count += 1
|
Chris@1464
|
432 logger.info "Deadlock detected on retry #{retry_count}, restarting transaction"
|
Chris@1464
|
433 sleep(rand(retry_count)*0.1) # Aloha protocol
|
Chris@1464
|
434 retry
|
Chris@1464
|
435 end
|
Chris@1464
|
436 end
|
Chris@1464
|
437
|
Chris@1464
|
438 # Prunes a branch off of the tree, shifting all of the elements on the right
|
Chris@1464
|
439 # back to the left so the counts still work.
|
Chris@1464
|
440 def destroy_descendants
|
Chris@1464
|
441 return if right.nil? || left.nil? || skip_before_destroy
|
Chris@1464
|
442
|
Chris@1464
|
443 in_tenacious_transaction do
|
Chris@1464
|
444 reload_nested_set
|
Chris@1464
|
445 # select the rows in the model that extend past the deletion point and apply a lock
|
Chris@1464
|
446 self.class.base_class.
|
Chris@1464
|
447 select("id").
|
Chris@1464
|
448 where("#{quoted_left_column_name} >= ?", left).
|
Chris@1464
|
449 lock(true).
|
Chris@1464
|
450 all
|
Chris@1464
|
451
|
Chris@1464
|
452 if acts_as_nested_set_options[:dependent] == :destroy
|
Chris@1464
|
453 descendants.each do |model|
|
Chris@1464
|
454 model.skip_before_destroy = true
|
Chris@1464
|
455 model.destroy
|
Chris@1464
|
456 end
|
Chris@1464
|
457 else
|
Chris@1464
|
458 nested_set_scope.delete_all(
|
Chris@1464
|
459 ["#{quoted_left_column_name} > ? AND #{quoted_right_column_name} < ?",
|
Chris@1464
|
460 left, right]
|
Chris@1464
|
461 )
|
Chris@1464
|
462 end
|
Chris@1464
|
463
|
Chris@1464
|
464 # update lefts and rights for remaining nodes
|
Chris@1464
|
465 diff = right - left + 1
|
Chris@1464
|
466 nested_set_scope.update_all(
|
Chris@1464
|
467 ["#{quoted_left_column_name} = (#{quoted_left_column_name} - ?)", diff],
|
Chris@1464
|
468 ["#{quoted_left_column_name} > ?", right]
|
Chris@1464
|
469 )
|
Chris@1464
|
470 nested_set_scope.update_all(
|
Chris@1464
|
471 ["#{quoted_right_column_name} = (#{quoted_right_column_name} - ?)", diff],
|
Chris@1464
|
472 ["#{quoted_right_column_name} > ?", right]
|
Chris@1464
|
473 )
|
Chris@1464
|
474
|
Chris@1464
|
475 reload
|
Chris@1464
|
476 # Don't allow multiple calls to destroy to corrupt the set
|
Chris@1464
|
477 self.skip_before_destroy = true
|
Chris@1464
|
478 end
|
Chris@1464
|
479 end
|
Chris@1464
|
480
|
Chris@1464
|
481 # reload left, right, and parent
|
Chris@1464
|
482 def reload_nested_set
|
Chris@1464
|
483 reload(
|
Chris@1464
|
484 :select => "#{quoted_left_column_name}, #{quoted_right_column_name}, #{quoted_parent_column_name}",
|
Chris@1464
|
485 :lock => true
|
Chris@1464
|
486 )
|
Chris@1464
|
487 end
|
Chris@1464
|
488
|
Chris@1464
|
489 def move_to(target, position)
|
Chris@1464
|
490 raise ActiveRecord::ActiveRecordError, "You cannot move a new node" if self.new_record?
|
Chris@1464
|
491 run_callbacks :move do
|
Chris@1464
|
492 in_tenacious_transaction do
|
Chris@1464
|
493 if target.is_a? self.class.base_class
|
Chris@1464
|
494 target.reload_nested_set
|
Chris@1464
|
495 elsif position != :root
|
Chris@1464
|
496 # load object if node is not an object
|
Chris@1464
|
497 target = nested_set_scope.find(target)
|
Chris@1464
|
498 end
|
Chris@1464
|
499 self.reload_nested_set
|
Chris@1464
|
500
|
Chris@1464
|
501 unless position == :root || move_possible?(target)
|
Chris@1464
|
502 raise ActiveRecord::ActiveRecordError, "Impossible move, target node cannot be inside moved tree."
|
Chris@1464
|
503 end
|
Chris@1464
|
504
|
Chris@1464
|
505 bound = case position
|
Chris@1464
|
506 when :child; target[right_column_name]
|
Chris@1464
|
507 when :left; target[left_column_name]
|
Chris@1464
|
508 when :right; target[right_column_name] + 1
|
Chris@1464
|
509 when :root; 1
|
Chris@1464
|
510 else raise ActiveRecord::ActiveRecordError, "Position should be :child, :left, :right or :root ('#{position}' received)."
|
Chris@1464
|
511 end
|
Chris@1464
|
512
|
Chris@1464
|
513 if bound > self[right_column_name]
|
Chris@1464
|
514 bound = bound - 1
|
Chris@1464
|
515 other_bound = self[right_column_name] + 1
|
Chris@1464
|
516 else
|
Chris@1464
|
517 other_bound = self[left_column_name] - 1
|
Chris@1464
|
518 end
|
Chris@1464
|
519
|
Chris@1464
|
520 # there would be no change
|
Chris@1464
|
521 return if bound == self[right_column_name] || bound == self[left_column_name]
|
Chris@1464
|
522
|
Chris@1464
|
523 # we have defined the boundaries of two non-overlapping intervals,
|
Chris@1464
|
524 # so sorting puts both the intervals and their boundaries in order
|
Chris@1464
|
525 a, b, c, d = [self[left_column_name], self[right_column_name], bound, other_bound].sort
|
Chris@1464
|
526
|
Chris@1464
|
527 # select the rows in the model between a and d, and apply a lock
|
Chris@1464
|
528 self.class.base_class.select('id').lock(true).where(
|
Chris@1464
|
529 ["#{quoted_left_column_name} >= :a and #{quoted_right_column_name} <= :d", {:a => a, :d => d}]
|
Chris@1464
|
530 )
|
Chris@1464
|
531
|
Chris@1464
|
532 new_parent = case position
|
Chris@1464
|
533 when :child; target.id
|
Chris@1464
|
534 when :root; nil
|
Chris@1464
|
535 else target[parent_column_name]
|
Chris@1464
|
536 end
|
Chris@1464
|
537
|
Chris@1464
|
538 self.nested_set_scope.update_all([
|
Chris@1464
|
539 "#{quoted_left_column_name} = CASE " +
|
Chris@1464
|
540 "WHEN #{quoted_left_column_name} BETWEEN :a AND :b " +
|
Chris@1464
|
541 "THEN #{quoted_left_column_name} + :d - :b " +
|
Chris@1464
|
542 "WHEN #{quoted_left_column_name} BETWEEN :c AND :d " +
|
Chris@1464
|
543 "THEN #{quoted_left_column_name} + :a - :c " +
|
Chris@1464
|
544 "ELSE #{quoted_left_column_name} END, " +
|
Chris@1464
|
545 "#{quoted_right_column_name} = CASE " +
|
Chris@1464
|
546 "WHEN #{quoted_right_column_name} BETWEEN :a AND :b " +
|
Chris@1464
|
547 "THEN #{quoted_right_column_name} + :d - :b " +
|
Chris@1464
|
548 "WHEN #{quoted_right_column_name} BETWEEN :c AND :d " +
|
Chris@1464
|
549 "THEN #{quoted_right_column_name} + :a - :c " +
|
Chris@1464
|
550 "ELSE #{quoted_right_column_name} END, " +
|
Chris@1464
|
551 "#{quoted_parent_column_name} = CASE " +
|
Chris@1464
|
552 "WHEN #{self.class.base_class.primary_key} = :id THEN :new_parent " +
|
Chris@1464
|
553 "ELSE #{quoted_parent_column_name} END",
|
Chris@1464
|
554 {:a => a, :b => b, :c => c, :d => d, :id => self.id, :new_parent => new_parent}
|
Chris@1464
|
555 ])
|
Chris@1464
|
556 end
|
Chris@1464
|
557 target.reload_nested_set if target
|
Chris@1464
|
558 self.reload_nested_set
|
Chris@1464
|
559 end
|
Chris@1464
|
560 end
|
Chris@1464
|
561
|
Chris@1464
|
562 end
|
Chris@1464
|
563
|
Chris@1464
|
564 # Mixed into both classes and instances to provide easy access to the column names
|
Chris@1464
|
565 module Columns
|
Chris@1464
|
566 def left_column_name
|
Chris@1464
|
567 acts_as_nested_set_options[:left_column]
|
Chris@1464
|
568 end
|
Chris@1464
|
569
|
Chris@1464
|
570 def right_column_name
|
Chris@1464
|
571 acts_as_nested_set_options[:right_column]
|
Chris@1464
|
572 end
|
Chris@1464
|
573
|
Chris@1464
|
574 def parent_column_name
|
Chris@1464
|
575 acts_as_nested_set_options[:parent_column]
|
Chris@1464
|
576 end
|
Chris@1464
|
577
|
Chris@1464
|
578 def scope_column_names
|
Chris@1464
|
579 Array(acts_as_nested_set_options[:scope])
|
Chris@1464
|
580 end
|
Chris@1464
|
581
|
Chris@1464
|
582 def quoted_left_column_name
|
Chris@1464
|
583 connection.quote_column_name(left_column_name)
|
Chris@1464
|
584 end
|
Chris@1464
|
585
|
Chris@1464
|
586 def quoted_right_column_name
|
Chris@1464
|
587 connection.quote_column_name(right_column_name)
|
Chris@1464
|
588 end
|
Chris@1464
|
589
|
Chris@1464
|
590 def quoted_parent_column_name
|
Chris@1464
|
591 connection.quote_column_name(parent_column_name)
|
Chris@1464
|
592 end
|
Chris@1464
|
593
|
Chris@1464
|
594 def quoted_scope_column_names
|
Chris@1464
|
595 scope_column_names.collect {|column_name| connection.quote_column_name(column_name) }
|
Chris@1464
|
596 end
|
Chris@1464
|
597 end
|
Chris@1464
|
598
|
Chris@1464
|
599 end
|
Chris@1464
|
600 end
|
Chris@1464
|
601 end
|