feat: support custom options on event and destinations (#12)

Gemfile.lock

@@ -1,28 +1,28 @@
 PATH
   remote: .
   specs:
-    event_router (0.2.0)
+    event_router (0.3.0)
       activesupport
 
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (6.0.3.2)
+    activesupport (6.1.1)
       concurrent-ruby (~> 1.0, >= 1.0.2)
-      i18n (>= 0.7, < 2)
-      minitest (~> 5.1)
-      tzinfo (~> 1.1)
-      zeitwerk (~> 2.2, >= 2.2.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+      zeitwerk (~> 2.3)
     ast (2.4.1)
     byebug (11.1.3)
     coderay (1.1.3)
-    concurrent-ruby (1.1.7)
+    concurrent-ruby (1.1.8)
     connection_pool (2.2.3)
     diff-lcs (1.3)
-    i18n (1.8.5)
+    i18n (1.8.7)
       concurrent-ruby (~> 1.0)
     method_source (1.0.0)
-    minitest (5.14.1)
+    minitest (5.14.3)
     oj (3.10.14)
     parallel (1.19.2)
     parser (2.7.1.4)
@@ -67,11 +67,10 @@ GEM
       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)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
     unicode-display_width (1.7.0)
-    zeitwerk (2.4.0)
+    zeitwerk (2.4.2)
 
 PLATFORMS
   ruby

examples/order_placed.rb

@@ -2,8 +2,11 @@
 
 module Examples
   class OrderPlaced < EventRouter::Event
+    event_options queue: :orders, retry: false
+
     deliver_to :notifications,
-               handler: Examples::Notifications
+               handler: Examples::Notifications,
+               queue: :notifications
 
     deliver_to :event_store,
                handler: Examples::EventStore::OrderPlaced,

examples/sidekiq/config.yml

@@ -1,3 +1,5 @@
 :concurrency: 1
 :queues:
   - [event_router, 1]
+  - [notifications, 2]
+  - [orders, 2]

lib/event_router/delivery_adapters/helpers/sidekiq.rb

@@ -6,12 +6,14 @@ module Helpers
       module Sidekiq
         module_function
 
+        extend EventRouter::Helpers::Event
+
         def process_event(event, serialized_event: nil)
           serialized_event ||= EventRouter.serialize(event)
 
-          options = EventRouter::DeliveryAdapters::Sidekiq.options
+          yield_destinations(event) do |destination, serialized_payload|
+            options = destination_options(destination, EventRouter::DeliveryAdapters::Sidekiq)
 
-          Helpers::Deliver.yield_destinations(event) do |destination, serialized_payload|
             Workers::SidekiqDestinationDeliveryWorker
               .set(queue: options[:queue], retry: options[:retry])
               .perform_async(destination.name, serialized_event, serialized_payload)

lib/event_router/delivery_adapters/sidekiq.rb

@@ -2,11 +2,10 @@
 
 require 'sidekiq'
 
-require_relative '../serializer'
+require 'event_router/serializer'
+require 'event_router/helpers/event'
 
-require_relative 'helpers/deliver'
 require_relative 'helpers/sidekiq'
-
 require_relative 'workers/sidekiq_destination_delivery_worker'
 require_relative 'workers/sidekiq_event_delivery_worker'
 
@@ -29,7 +28,8 @@ def deliver(event)
         end
 
         def deliver_async(event)
-          serialized_event = EventRouter.serialize(event)
+          serialized_event  = EventRouter.serialize(event)
+          options           = EventRouter::Helpers::Event.event_options(event, self)
 
           Workers::SidekiqEventDeliveryWorker
             .set(queue: options[:queue], retry: options[:retry])

lib/event_router/destination.rb

@@ -4,7 +4,8 @@ module EventRouter
   class Destination
     # Attributes
     attr_reader :name, :handler, :handler_method,
-                :prefetch_payload, :payload_method
+                :prefetch_payload, :payload_method,
+                :options
 
     # Constants
     DEFAULT_ATTRIBUTES = {
@@ -22,9 +23,10 @@ def initialize(name, handler:, **opts)
 
       @name             = name
       @handler          = handler
-      @handler_method   = opts[:handler_method]
-      @prefetch_payload = opts[:prefetch_payload]
-      @payload_method   = opts[:payload_method] || "#{name}_payload"
+      @handler_method   = opts.delete(:handler_method)
+      @prefetch_payload = opts.delete(:prefetch_payload)
+      @payload_method   = opts.delete(:payload_method) || "#{name}_payload"
+      @options          = opts
     end
 
     def process(event, payload)

lib/event_router/event.rb

@@ -12,6 +12,7 @@ class Event
     attr_accessor :correlation_id
 
     class_attribute :destinations, default: {}, instance_writer: false
+    class_attribute :options, instance_writer: false
 
     def initialize(uid: SecureRandom.uuid, correlation_id: SecureRandom.uuid, created_at: Time.now, **payload)
       @uid            = uid
@@ -45,6 +46,10 @@ def deliver_to(name, opts = {})
         destinations[name] = EventRouter::Destination.new(name, **opts)
       end
 
+      def event_options(opts)
+        self.options = opts
+      end
+
       def publish(**attrs)
         EventRouter.publish(new(**attrs))
       end

lib/event_router/helpers/event.rb

@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+module EventRouter
+  module Helpers
+    module Event
+      module_function
+
+      def yield_destinations(event)
+        event.destinations.each do |_name, destination|
+          if destination.prefetch_payload?
+            payload             = destination.extra_payload(event)
+            serialized_payload  = EventRouter.serialize(payload)
+          end
+
+          yield destination, serialized_payload if block_given?
+        end
+      end
+
+      def event_options(event, adapter)
+        return adapter.options unless event.options?
+
+        adapter.options.merge(event.options)
+      end
+
+      def destination_options(destination, adapter)
+        adapter.options.merge(destination.options)
+      end
+    end
+  end
+end

lib/event_router/version.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module EventRouter
-  VERSION = '0.2.0'
+  VERSION = '0.3.0'
 end

spec/event_router/helpers/event_spec.rb

@@ -0,0 +1,74 @@
+require 'event_router/helpers/event'
+
+RSpec.describe EventRouter::Helpers::Event do
+  describe '.yield_destinations' do
+    subject { described_class.yield_destinations(event) }
+
+    let(:event) { DummyEvent.new }
+
+    let(:expected_args) do
+      event.destinations.map { |_, destination| [destination, anything] }
+    end
+
+    it 'yields the event destinations with serialized payload' do
+      expect { |b| described_class.yield_destinations(event, &b) }.to yield_successive_args(*expected_args)
+    end
+
+    it 'serializes the payload' do
+      expect(EventRouter).to receive(:serialize).once
+
+      subject
+    end
+  end
+
+  describe '.event_options' do
+    subject { described_class.event_options(event, adapter) }
+
+    let(:event)           { DummyEvent.new }
+    let(:adapter)         { DummyDeliveryAdapter }
+    let(:adapter_options) { { option_1: :adapter, option_2: :adapter } }
+
+    before { allow(adapter).to receive(:options) { adapter_options } }
+
+    context 'when event has custom options' do
+      let(:event_options) { { option_1: :event } }
+
+      before { allow(event).to receive(:options) { event_options } }
+
+      it 'merges the event options to the adapter options' do
+        is_expected.to eq(option_1: :event, option_2: :adapter)
+      end
+    end
+
+    context 'when event does not have any custom options' do
+      it 'returns the adapter options' do
+        is_expected.to eq(adapter_options)
+      end
+    end
+  end
+
+  describe '.destination_options' do
+    subject { described_class.destination_options(destination, adapter) }
+
+    let(:adapter)         { DummyDeliveryAdapter }
+    let(:adapter_options) { { option_1: :adapter, option_2: :adapter } }
+
+    before { allow(adapter).to receive(:options) { adapter_options } }
+
+    context 'when destination has custom options' do
+      let(:destination) { EventRouter::Destination.new(:notifications, handler: :any, option_1: :destination) }
+
+      it 'merges the destination options to the adapter options' do
+        is_expected.to eq(option_1: :destination, option_2: :adapter)
+      end
+    end
+
+    context 'when destination does not have any custom options' do
+      let(:destination) { EventRouter::Destination.new(:notifications, handler: :any) }
+
+      it 'returns the adapter options' do
+        is_expected.to eq(adapter_options)
+      end
+    end
+  end
+end