ci: Add ActionMailer CI (open-telemetry#976)

* ci: Add ActionMailer CI

* ci: Linter fixes

* squash: drop pry-byebug

.github/workflows/ci-instrumentation.yml

@@ -21,6 +21,7 @@ jobs:
       fail-fast: false
       matrix:
         gem:
+          - action_mailer
           - action_pack
           - action_view
           - active_job

instrumentation/action_mailer/Gemfile

@@ -11,5 +11,4 @@ gemspec
 group :test do
   gem 'opentelemetry-instrumentation-base', path: '../base'
   gem 'opentelemetry-instrumentation-active_support', path: '../active_support'
-  gem 'pry-byebug'
 end

instrumentation/action_mailer/lib/opentelemetry/instrumentation/action_mailer/instrumentation.rb

@@ -10,7 +10,7 @@ module ActionMailer
       # The Instrumentation class contains logic to detect and install the ActionMailer instrumentation
       class Instrumentation < OpenTelemetry::Instrumentation::Base
         MINIMUM_VERSION = Gem::Version.new('6.1.0')
-        EMAIL_ATTRIBUTE = ['email.to.address', 'email.from.address', 'email.cc.address', 'email.bcc.address']
+        EMAIL_ATTRIBUTE = %w[email.to.address email.from.address email.cc.address email.bcc.address].freeze
 
         install do |_config|
           resolve_email_address

instrumentation/action_mailer/opentelemetry-instrumentation-action_mailer.gemspec

@@ -34,7 +34,6 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'minitest', '~> 5.0'
   spec.add_development_dependency 'opentelemetry-sdk', '~> 1.1'
   spec.add_development_dependency 'opentelemetry-test-helpers', '~> 0.3'
-  spec.add_development_dependency 'rails', '>= 6.1'
   spec.add_development_dependency 'rake', '~> 13.0'
   spec.add_development_dependency 'rubocop', '~> 1.60.1'
   spec.add_development_dependency 'rubocop-performance', '~> 1.20'

instrumentation/action_mailer/test/opentelemetry/instrumentation/action_mailer/instrumentation_test.rb

@@ -10,14 +10,14 @@
   let(:instrumentation) { OpenTelemetry::Instrumentation::ActionMailer::Instrumentation.instance }
   let(:payload) do
     {
-      :mailer => "TestMailer",
-      :message_id => "[email protected]",
-      :subject => "Welcome to OpenTelemetry!",
-      :to => ["[email protected]"],
-      :from => ["[email protected]"],
-      :bcc => ["[email protected]"],
-      :cc => ["[email protected]"],
-      :perform_deliveries => true
+      mailer: 'TestMailer',
+      message_id: '[email protected]',
+      subject: 'Welcome to OpenTelemetry!',
+      to: ['[email protected]'],
+      from: ['[email protected]'],
+      bcc: ['[email protected]'],
+      cc: ['[email protected]'],
+      perform_deliveries: true
     }
   end
 
@@ -62,14 +62,14 @@
   describe '#transform_payload' do
     it 'with simple payload' do
       payload = {
-        :mailer => "TestMailer",
-        :message_id => "[email protected]",
-        :subject => "Welcome to OpenTelemetry!",
-        :to => ["[email protected]"],
-        :from => ["[email protected]"],
-        :bcc => ["[email protected]"],
-        :cc => ["[email protected]"],
-        :perform_deliveries => true
+        mailer: 'TestMailer',
+        message_id: '[email protected]',
+        subject: 'Welcome to OpenTelemetry!',
+        to: ['[email protected]'],
+        from: ['[email protected]'],
+        bcc: ['[email protected]'],
+        cc: ['[email protected]'],
+        perform_deliveries: true
       }
       tranformed_payload = instrumentation.send(:transform_payload, payload)
 
@@ -85,15 +85,14 @@
 
   describe '#ecs_mail_convention' do
     it 'with user-defined payload' do
-
       original_config = instrumentation.instance_variable_get(:@config)
       modified_config = original_config.dup
 
-      modified_config[:notification_payload_transform] = lambda { |payload| payload['email.message_id'] = 'fake_message_id' }
+      modified_config[:notification_payload_transform] = ->(payload) { payload['email.message_id'] = 'fake_message_id' }
       instrumentation.instance_variable_set(:@config, modified_config)
 
       instrumentation.send(:ecs_mail_convention)
-      payload = { :mailer => "TestMailer"}
+      payload = { mailer: 'TestMailer' }
 
       tranformed_payload = instrumentation.config[:notification_payload_transform].call(payload)
 
@@ -103,7 +102,6 @@
     end
 
     it 'without user-defined payload' do
-
       tranformed_payload = instrumentation.config[:notification_payload_transform].call(payload)
 
       _(tranformed_payload['email.message_id']).must_equal '[email protected]'