How to generate a specific Date on Ruby

somocode.rb

require 'date'

# Today
Date.today

# 1st of this month
Date.new(Time.now.year, Time.now.month, 1)

# 1st of next month
Date.new(Time.now.year, Time.now.month, 1) >> 1

# 1st of last month
Date.new(Time.now.year, Time.now.month, 1) << 1

# 1 week later
Date.today + 7

# 1 week before
Date.today - 7

And you can use these Date valuables in Model 'where' phrase on Rails.

somocode.rb

models = SomeModel.where("date <= ?", Date.today)