find_redundant.rb

# This script greps the code base for all associations with an explicit foreign_key.
# For each defined association, it attempts to infer the foreign_key using our inflection rules.
# If the inferred foreign_key matches the explicit foreign_key, then the foreign_key declaration can be removed.
# If not, then there is the potential that the inflection can be added to config/initializers/inflections
# (unless it is an exception to an already-defined initializer inflection)
# USAGE: run from the command line
# $ ruby find_redundant_foreign_keys.rb

root = File.expand_path(File.dirname(__FILE__) + '/../')

require 'rubygems'
require 'bundler/setup'
require 'iktiv_record'
require 'logger'
require File.expand_path(root + '/config/initializers/inflections')

class ForeignKeyDeclaration
  def initialize(defined, class_name)
    @defined, @class_name = defined, class_name
  end

  def verify
    unless composite_key?
      puts "#{redundant?.to_s.upcase}: :#{@class_name}, :foreign_key => :#{@defined} (derived as :#{derived_foreign_key.downcase})"
    end
  end

  private
  def composite_key?
    @defined.is_a? Array
  end

  def redundant?
    (derived_foreign_key.upcase == @defined.to_s.upcase)? :redundant : :defined
  end

  def derived_foreign_key
    @class_name.to_s.foreign_key
  end
end

def belongs_to(assoc, hash)
  ForeignKeyDeclaration.new(hash[:foreign_key], assoc).verify
end

def has_many(assoc, hash)
  ForeignKeyDeclaration.new(hash[:foreign_key], hash[:filename]).verify
end

def has_one(assoc, hash)
  ForeignKeyDeclaration.new(hash[:foreign_key], hash[:filename]).verify
end

def set_table_name(table_name, class_name)
  redundant = (class_name.to_s.pluralize == table_name.to_s)? :redundant : :defined
  puts "#{redundant.to_s.upcase}: #{class_name.to_s.classify}, set_table_name :#{table_name} (derived as :#{class_name.to_s.pluralize})"
end

puts "\n=== belongs_to ==="
eval `grep -hr -e "belongs_to .* :foreign_key" #{root}/models/ | sed -e 's/^ *//' -e 's/^base\\.//'`

puts "\n=== has_many ==="
eval `grep -r -e "has_many .* :foreign_key" #{root}/models/ | sed -e 's/^.*\\/models\\/[a-z\\/]*\\/\\([a-z_0-9]*\\).rb\\(.*\\)has_many\\(.*\\)\\(=.\\)\\(.*\\)/has_many\\3\\4\\5, :filename \\4 :\\1/'`

puts "\n=== has_one ==="
eval `grep -r -e "has_one .* :foreign_key" #{root}/models/ | sed -e 's/^.*\\/models\\/[a-z\\/]*\\/\\([a-z_0-9]*\\).rb\\(.*\\)has_one\\(.*\\)\\(=.\\)\\(.*\\)/has_one\\3\\4\\5, :filename \\4 :\\1/'`

puts "\n=== set_table_name ==="
eval `grep -r -e "set_table_name .*" #{root}/models/ | sed -e 's/^.*\\/models\\/[a-z\\/]*\\/\\([a-z_0-9]*\\).rb\\(.*\\)set_table_name\\(.*\\)/set_table_name\\3, :\\1/'`