From e56132c50692771b3d315d944e3a279852a4251e Mon Sep 17 00:00:00 2001
From: Subin T P <subinthattaparambil@gmail.com>
Date: Sun, 29 Mar 2020 19:18:30 +0530
Subject: [PATCH] Non blocking  event dispatch (#652)

- Performance improvements for event dispatch
---
 app/dispatchers/async_dispatcher.rb       |  5 ++++-
 app/jobs/event_dispatcher_job.rb          |  7 +++++++
 config/sidekiq.yml                        |  3 ++-
 spec/builders/v2/report_builder_spec.rb   | 10 ++++++++++
 spec/dispatchers/async_dispatcher_spec.rb | 16 ++++++++++++++++
 spec/jobs/event_dispatcher_job_spec.rb    | 22 ++++++++++++++++++++++
 6 files changed, 61 insertions(+), 2 deletions(-)
 create mode 100644 app/jobs/event_dispatcher_job.rb
 create mode 100644 spec/dispatchers/async_dispatcher_spec.rb
 create mode 100644 spec/jobs/event_dispatcher_job_spec.rb

diff --git a/app/dispatchers/async_dispatcher.rb b/app/dispatchers/async_dispatcher.rb
index cce44c97a..65569c1b0 100644
--- a/app/dispatchers/async_dispatcher.rb
+++ b/app/dispatchers/async_dispatcher.rb
@@ -1,7 +1,10 @@
 class AsyncDispatcher < BaseDispatcher
   def dispatch(event_name, timestamp, data)
+    EventDispatcherJob.perform_later(event_name, timestamp, data)
+  end
+
+  def publish_event(event_name, timestamp, data)
     event_object = Events::Base.new(event_name, timestamp, data)
-    # TODO: Move this to worker
     publish(event_object.method_name, event_object)
   end
 
diff --git a/app/jobs/event_dispatcher_job.rb b/app/jobs/event_dispatcher_job.rb
new file mode 100644
index 000000000..c08d52d74
--- /dev/null
+++ b/app/jobs/event_dispatcher_job.rb
@@ -0,0 +1,7 @@
+class EventDispatcherJob < ApplicationJob
+  queue_as :events
+
+  def perform(event_name, timestamp, data)
+    Rails.configuration.dispatcher.async_dispatcher.publish_event(event_name, timestamp, data)
+  end
+end
diff --git a/config/sidekiq.yml b/config/sidekiq.yml
index 8dc7f5ede..b876886ee 100644
--- a/config/sidekiq.yml
+++ b/config/sidekiq.yml
@@ -17,7 +17,8 @@
   - [mailers, 2]
   - [webhooks, 1]
   - [bots, 1]
-
+  - [events, 3]
+  
 # you can override concurrency based on environment
 production:
   :concurrency: 10
diff --git a/spec/builders/v2/report_builder_spec.rb b/spec/builders/v2/report_builder_spec.rb
index 02a2fc4ab..4aef6c425 100644
--- a/spec/builders/v2/report_builder_spec.rb
+++ b/spec/builders/v2/report_builder_spec.rb
@@ -6,6 +6,16 @@ describe ::V2::ReportBuilder do
   let!(:inbox) { create(:inbox, account: account) }
   let(:inbox_member) { create(:inbox_member, user: user, inbox: inbox) }
 
+  # Running jobs inline to calculate the exact metrics
+  around do |test|
+    current_adapter = ActiveJob::Base.queue_adapter
+    ActiveJob::Base.queue_adapter = :inline
+
+    test.run
+  ensure
+    ActiveJob::Base.queue_adapter = current_adapter
+  end
+
   describe '#timeseries' do
     context 'when report type is account' do
       before do
diff --git a/spec/dispatchers/async_dispatcher_spec.rb b/spec/dispatchers/async_dispatcher_spec.rb
new file mode 100644
index 000000000..b108fd962
--- /dev/null
+++ b/spec/dispatchers/async_dispatcher_spec.rb
@@ -0,0 +1,16 @@
+require 'rails_helper'
+describe AsyncDispatcher do
+  subject(:dispatcher) { described_class.new }
+
+  let!(:conversation) { create(:conversation) }
+  let(:event_name) { 'conversation.created' }
+  let(:timestamp) { Time.zone.now }
+  let(:event_data) { { conversation: conversation } }
+
+  describe '#dispatch' do
+    it 'enqueue job to dispatch event' do
+      expect(EventDispatcherJob).to receive(:perform_later).with(event_name, timestamp, event_data).once
+      dispatcher.dispatch(event_name, timestamp, event_data)
+    end
+  end
+end
diff --git a/spec/jobs/event_dispatcher_job_spec.rb b/spec/jobs/event_dispatcher_job_spec.rb
new file mode 100644
index 000000000..14da570b2
--- /dev/null
+++ b/spec/jobs/event_dispatcher_job_spec.rb
@@ -0,0 +1,22 @@
+require 'rails_helper'
+
+RSpec.describe EventDispatcherJob, type: :job do
+  subject(:job) { described_class.perform_later(event_name, timestamp, event_data) }
+
+  let!(:conversation) { create(:conversation) }
+  let(:event_name) { 'conversation.created' }
+  let(:timestamp) { Time.zone.now }
+  let(:event_data) { { conversation: conversation } }
+
+  it 'queues the job' do
+    expect { job }.to have_enqueued_job(described_class)
+      .with(event_name, timestamp, event_data)
+      .on_queue('events')
+  end
+
+  it 'publishes event' do
+    expect(Rails.configuration.dispatcher.async_dispatcher).to receive(:publish_event).with(event_name, timestamp, event_data).once
+    event_dispatcher = described_class.new
+    event_dispatcher.perform(event_name, timestamp, event_data)
+  end
+end