Set consistent context in delayed_job integration

CHANGELOG.md

@@ -1,6 +1,14 @@
 Changelog
 =========
 
+## TBD
+
+### Enhancements
+
+* Set default Delayed Job error context to job class
+  | [#499](https://github.com/bugsnag/bugsnag-ruby/pull/499)
+  | [Mike Stewart](https://github.com/mike-stewart)
+
 ## 6.15.0 (27 July 2020)
 
 ### Enhancements

features/delayed_job.feature

@@ -34,3 +34,20 @@ Scenario: A handled exception sends a report
   And the event "metaData.job.payload.display_name" equals "TestModel.notify_with_args"
   And the event "metaData.job.payload.method_name" equals "notify_with_args"
   And the payload field "events.0.metaData.job.payload.args.0" equals "Test"
+
+Scenario: The report context uses the class name if no display name is available
+  Given I run the service "delayed_job" with the command "bundle exec rake delayed_job_tests:report_context"
+  And I wait to receive a request
+  Then the request is valid for the error reporting API version "4.0" for the "Ruby Bugsnag Notifier"
+  And the event "unhandled" is true
+  And the event "severity" equals "error"
+  And the event "context" equals "TestReportContextJob"
+  And the event "severityReason.type" equals "unhandledExceptionMiddleware"
+  And the event "severityReason.attributes.framework" equals "DelayedJob"
+  And the exception "errorClass" equals "RuntimeError"
+  And the event "metaData.job.class" equals "Delayed::Backend::ActiveRecord::Job"
+  And the event "metaData.job.id" is not null
+  And the event "metaData.job.attempt" equals 1
+  And the event "metaData.job.max_attempts" equals 1
+  And the event "metaData.job.payload.display_name" is null
+  And the event "metaData.job.payload.method_name" is null

features/fixtures/delayed_job/app/Rakefile

@@ -13,6 +13,10 @@ namespace :delayed_job_tests do
   task :notify_with_args do
     run_delayed_job_test('"TestModel.delay.notify_with_args(\"Test\")"')
   end
+
+  task :report_context do
+    run_delayed_job_test('"Delayed::Job.enqueue TestReportContextJob.new"')
+  end
 end
 
 def run_delayed_job_test(command)
@@ -21,4 +25,4 @@ def run_delayed_job_test(command)
   end
   system("rails runner #{command}")
   Process.wait
-end
+end

features/fixtures/delayed_job/app/app/jobs/test_report_context_job.rb

@@ -0,0 +1,7 @@
+class TestReportContextJob < ApplicationJob
+  queue_as :default
+
+  def perform(*)
+    raise "oh dear"
+  end
+end

lib/bugsnag/middleware/delayed_job.rb

@@ -24,6 +24,7 @@ def call(report)
           job_data[:active_job] = job.payload_object.job_data if job.payload_object.respond_to?(:job_data)
           payload_data = construct_job_payload(job.payload_object)
           report.context = payload_data[:display_name] if payload_data.include?(:display_name)
+          report.context ||= payload_data[:class] if payload_data.include?(:class)
           job_data[:payload] = payload_data
         end