Simple Wisper example

wisper_example.rb

require 'wisper'

class User
  include Wisper::Publisher
  attr_accessor :name, :last_email_sent_at

  def initialize(name, email)
    @name, @email = name, email
  end

  def create
    # Do stuff to create the user
    broadcast(:user_created, self)
  end

  def destroy
    # Do stuff to destroy the user
    broadcast(:user_destroyed, self)
  end

  def rename(string)
    self.name = string
    broadcast(:user_renamed, self)
  end
end

class EmailListener
  def user_created(user)
    # Do stuff that sends a welcome email
    user.last_email_sent_at = Time.now
    puts "Welcome email was sent to #{user.email}"
  end

  def user_destroyed(user)
    # Do stuff that sends a farewell email
    user.last_email_sent_at = Time.now
    puts "Farewell email was sent to #{user.email}"
  end
end

john = User.new('John', '[email protected]')
# => #<User:0x007fb1afc3ccc0 @email="[email protected]", @name="John">
john.subscribe(EmailListener.new)
# => #<User:0x007fb1afc3ccc0
#  @email="[email protected]",
#  @local_registrations=
#   #<Set: {#<Wisper::ObjectRegistration:0x007fb1b0818f30
#     @allowed_classes=#<Set: {}>,
#     @broadcaster=#<Wisper::Broadcasters::SendBroadcaster:0x007fb1af067710>,
#     @listener=#<EmailListener:0x007fb1b0818fd0>,
#     @on=["all"],
#     @prefix="",
#     @with=nil>}>,
#  @name="John">
john.last_email_sent_at
# => nil
john.create
# Welcome email was sent to [email protected]
# => #<Set: {#<Wisper::ObjectRegistration:0x007fb1b0818f30
john.last_email_sent_at
# => 2015-02-14 19:39:48 +0100
john.destroy
# Farewell email was sent to [email protected]
# => #<Set: {#<Wisper::ObjectRegistration:0x007fb1b0818f30
john.last_email_sent_at
# => 2015-02-14 19:40:20 +0100
john.rename('Richard')
# => #<Set: {#<Wisper::ObjectRegistration:0x007fb1b0818f30
john.name
# => "Richard"