add event and event serializers logic

.gitignore

@@ -9,3 +9,6 @@
 
 # rspec failure tracking
 .rspec_status
+
+# Debug
+.byebug_history

Gemfile.lock

@@ -2,12 +2,40 @@ PATH
   remote: .
   specs:
     event_router (0.1.0)
+      activejob
 
 GEM
   remote: https://rubygems.org/
   specs:
+    activejob (6.0.3.2)
+      activesupport (= 6.0.3.2)
+      globalid (>= 0.3.6)
+    activesupport (6.0.3.2)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 0.7, < 2)
+      minitest (~> 5.1)
+      tzinfo (~> 1.1)
+      zeitwerk (~> 2.2, >= 2.2.2)
+    byebug (11.1.3)
+    coderay (1.1.3)
+    concurrent-ruby (1.1.7)
+    connection_pool (2.2.3)
     diff-lcs (1.3)
+    globalid (0.4.2)
+      activesupport (>= 4.2.0)
+    i18n (1.8.5)
+      concurrent-ruby (~> 1.0)
+    method_source (1.0.0)
+    minitest (5.14.1)
+    pry (0.13.1)
+      coderay (~> 1.1)
+      method_source (~> 1.0)
+    pry-byebug (3.9.0)
+      byebug (~> 11.0)
+      pry (~> 0.13.0)
+    rack (2.2.3)
     rake (12.3.3)
+    redis (4.2.1)
     rspec (3.9.0)
       rspec-core (~> 3.9.0)
       rspec-expectations (~> 3.9.0)
@@ -21,14 +49,24 @@ GEM
       diff-lcs (>= 1.2.0, < 2.0)
       rspec-support (~> 3.9.0)
     rspec-support (3.9.1)
+    sidekiq (6.1.1)
+      connection_pool (>= 2.2.2)
+      rack (~> 2.0)
+      redis (>= 4.2.0)
+    thread_safe (0.3.6)
+    tzinfo (1.2.7)
+      thread_safe (~> 0.1)
+    zeitwerk (2.4.0)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
   event_router!
+  pry-byebug
   rake (~> 12.0)
   rspec (~> 3.0)
+  sidekiq
 
 BUNDLED WITH
    2.1.4

event_router.gemspec

@@ -24,4 +24,11 @@ Gem::Specification.new do |spec|
   spec.bindir        = "exe"
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
+
+  # Dependencies
+  spec.add_dependency "activejob"
+
+  # Development dependencies
+  spec.add_development_dependency "sidekiq"
+  spec.add_development_dependency "pry-byebug"
 end

lib/event_router.rb

@@ -1,6 +1,33 @@
 require "event_router/version"
+require "event_router/error"
+require "active_job"
+require "event_router/destination"
+require "event_router/event"
+require "event_router/event_serializer"
+require "event_router/deliver_event_job"
+
+require "examples/order_placed"
+
+require "pry"
 
 module EventRouter
-  class Error < StandardError; end
-  # Your code goes here...
+  module_function
+
+  def run_example
+    ActiveJob::Serializers.add_serializers EventSerializer
+
+    Examples::OrderPlaced.publish(order_id: 1)
+  end
+
+  def publish(event)
+    DeliverEventJob.perform_later(:notifications, event)
+  end
+
+  # def publish(events)
+  #   events = Array(events)
+  #
+  #   events.map(&:destinations).flatten.each do |destination|
+  #     DeliverEventJob.perform_later(destination, event: event)
+  #   end
+  # end
 end

lib/event_router/deliver_event_job.rb

@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+require "pry"
+
+module EventRouter
+  class DeliverEventJob < ActiveJob::Base
+    self.queue_adapter = :sidekiq
+
+    def perform(destination, event)
+      binding.pry
+      event.destinations[destination]&.process(event)
+    end
+  end
+end

lib/event_router/destination.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+module EventRouter
+  class Destination
+    attr_reader :name, :handler, :handler_method
+
+    def initialize(name, handler:, method: nil)
+      @name           = name
+      @handler        = handler
+      @handler_method = method
+    end
+
+    def process(event)
+      @handler_method ||= event.underscore_name
+
+      handler.send(handler_method, event)
+    end
+  end
+end

lib/event_router/error.rb

@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+module EventRouter
+  class Error < StandardError; end
+end
+

lib/event_router/event.rb

@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+require "securerandom"
+
+module EventRouter
+  class Event
+    attr_reader :uid, :correlation_id, :created_at, :payload
+
+    class_attribute :destinations, default: {}, instance_writer: false
+
+    def initialize(uid: SecureRandom.uuid, correlation_id: SecureRandom.uuid, created_at: Time.current, **payload)
+      @uid            = uid
+      @correlation_id = correlation_id
+      @created_at     = created_at
+      @payload        = payload
+    end
+
+    def to_hash
+      {
+        uid: uid,
+        correlation_id: correlation_id,
+        payload: payload,
+        created_at: created_at,
+        _er_klass: self.class.name
+      }
+    end
+
+    def underscore_name
+      self.class.name.demodulize.underscore
+    end
+
+    class << self
+      def inherited(base)
+        base.destinations = destinations.dup
+        super
+      end
+
+      def deliver_to(name, opts = {})
+        destinations[name] = EventRouter::Destination.new(name, **opts)
+      end
+
+      def publish(**attrs)
+        event = new(**attrs)
+
+        EventRouter.publish(event)
+      end
+    end
+  end
+end

lib/event_router/event_serializer.rb

@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+module EventRouter
+  class EventSerializer < ActiveJob::Serializers::ObjectSerializer
+    def serialize(event)
+      event_attrs         = event.to_hash
+      payload             = event_attrs.delete(:payload)
+      serialized_payload  = ActiveJob::Arguments.serialize(payload)
+      serialized_event    = super(event_attrs)
+
+      serialized_event.merge(payload: serialized_payload)
+    end
+
+    def deserialize(hash)
+      hash["_er_klass"].constantize.new(
+        uid: hash["uid"],
+        correlation_id: hash["correlation_id"],
+        created_at: Time.parse(hash["created_at"]),
+        **ActiveJob::Arguments.deserialize(hash["payload"]).to_h
+      )
+    end
+
+  private
+
+    def klass
+      Event
+    end
+  end
+end

lib/examples/event_store/order_placed.rb

@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+module EventRouter
+  module Examples
+    module EventStore
+      class OrderPlaced
+        def self.handle(event)
+          binding.pry
+          true
+        end
+      end
+    end
+  end
+end

lib/examples/notifications.rb

@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+module EventRouter
+  module Examples
+    module Notifications
+    module_function
+
+      def order_placed(event)
+        binding.pry
+        true
+      end
+    end
+  end
+end

lib/examples/order_placed.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+require_relative "notifications"
+require_relative "event_store/order_placed"
+
+module EventRouter
+  module Examples
+    class OrderPlaced < EventRouter::Event
+      deliver_to :notifications,
+        handler: EventRouter::Examples::Notifications
+
+      deliver_to :event_store,
+        handler: EventRouter::Examples::EventStore::OrderPlaced,
+        method: :handle
+    end
+  end
+end

sidekiq.yml

@@ -0,0 +1,2 @@
+:queues:
+  - [default, 1]