Module: HierarchicalDb

Extended by:
ActiveSupport::Concern
Defined in:
lib/hierarchical_db.rb,
lib/hierarchical_db/version.rb,
lib/generators/hierarchical_db_generator.rb

Defined Under Namespace

Modules: ClassMethods, Generators

Constant Summary collapse

VERSION = 
"0.1.0"

Instance Method Summary collapse

Instance Method Details

#all_nodes ⇒ Object 



48
49
50
 
# File 'lib/hierarchical_db.rb', line 48

def all_nodes
  self.class.where(lft: (self.lft..self.rgt)).order(:lft)
end

#brothers ⇒ Object 



64
65
66
 
# File 'lib/hierarchical_db.rb', line 64

def brothers
  self.class.where("lft > ? and rgt < ?",self.parent.lft, self.parent.rgt)
end

#childs ⇒ Object 



60
61
62
 
# File 'lib/hierarchical_db.rb', line 60

def childs
  descendants.where(:lvl => self.lvl + 1)
end

#descendants ⇒ Object 



52
53
54
 
# File 'lib/hierarchical_db.rb', line 52

def descendants
  self.class.where(lft: (self.lft + 1..self.rgt - 1)).order(:lft)
end

#descendants_count ⇒ Object 



56
57
58
 
# File 'lib/hierarchical_db.rb', line 56

def descendants_count
  (self.rgt - self.lft - 1)/2
end

#destroy_node ⇒ Object 



113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
 
# File 'lib/hierarchical_db.rb', line 113

def destroy_node
  unless self.class.is_sorted?
    return
  end
  childs = self.class.where("lft > ?", self.rgt)
  childs.each do |t|
    t.lft = t.lft - 2
    t.save
  end
  childs = self.class.where("rgt > ?", self.rgt)
  childs.each do |t|
    t.rgt = t.rgt - 2
    t.save
  end
end

#display_subtree ⇒ Object 



129
130
131
132
133
134
135
136
137
138
139
140
141
 
# File 'lib/hierarchical_db.rb', line 129

def display_subtree
  right = []
  self.all_nodes.each do |d|
    if right.length > 0
      while right.last < d.rgt do
        right.pop
      end 
    end
    puts ("  "*right.length) +"#{d.id}-" +d.name
    right << d.rgt
  end
  return ''
end

#insert_node ⇒ Object 



72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
 
# File 'lib/hierarchical_db.rb', line 72

def insert_node
  unless self.class.is_sorted?
    return
  end
  father = self.parent
  previous_right = ""
  lvl = ""
  #case it has descendants
  unless father.nil?
    last_brother = father.descendants.where(:rgt => father.descendants.maximum(:rgt))
    #case has brothers
    unless last_brother.empty?
      last_brother = last_brother[0]
      previous_right = last_brother.rgt
      lvl = last_brother.lvl
    #case hasn't brothers
    else
      previous_right = father.rgt - 1
      lvl = father.lvl + 1 
    end
    childs = self.class.where("lft > ?", previous_right)
    childs.each do |t|
      t.lft = t.lft + 2
      t.save
    end
    childs = self.class.where("rgt > ?", previous_right)
    childs.each do |t|
      t.rgt = t.rgt + 2
      t.save
    end
  #case it is root
  else
    last_brother = self.class.where(:rgt => self.class.maximum(:rgt))
    last_brother = last_brother[0]
    previous_right = last_brother.rgt
  end
  self.lft = previous_right + 1
  self.rgt = previous_right + 2
  self.lvl = lvl
end

#list_by_level(lvl) ⇒ Object 



68
69
70
 
# File 'lib/hierarchical_db.rb', line 68

def list_by_level lvl
  self.class.where(:lvl => lvl)
end

#path(joined = nil, included = false) ⇒ Object 



143
144
145
146
147
148
 
# File 'lib/hierarchical_db.rb', line 143

def path(joined = nil, included = false)
  inc = included ? "=" : ""
  nodes = self.class.where("lft <#{inc} ?", self.lft).where("rgt >#{inc} ?", self.rgt).order(:lft)
  return nodes.map(&:name).join(joined) unless joined.nil?
  return nodes
end

#sort_subtree(left, lvl) ⇒ Object 



38
39
40
41
42
43
44
45
46
 
# File 'lib/hierarchical_db.rb', line 38

def sort_subtree left, lvl
  right = left + 1
  self.children.each{|child| right = child.sort_subtree(right, lvl + 1) }
  self.lft = left
  self.rgt = right
  self.lvl = lvl
  self.save
  return right + 1
end