post_querying.rb

class PostsQuery < ActiveRecord::Base
  self.table_name = "posts"

  belongs_to :user

  def self.report_filtering(filters)
    filters.inject(self) do |klass, (method_name, args)|
      klass.try("by_#{method_name}", args) || klass.current_scope
    end
  end

  def self.by_users(users)
    return current_scope unless users.present?

    joins(:user).where(users: users)
  end

  def self.by_created_at_start_date(created_at_start_date)
    return current_scope unless created_at_start_date.present?

    where(created_at: created_at_start_date..)
  end
end

puts PostsQuery.report_filtering(
  users: [User.find(1), User.find(5)],
  created_at_start_date: Date.current,
  created_at_end_date: Date.current,
  updated_at_start_date: Date.current,
  updated_at_end_date: Date.current,
).to_sql