Debugging Jobs

Introduction

When jobs fail, the debugging experience differs from web requests — no browser, no request log, failure may have happened hours ago.

Key Concepts

• Failed Execution: Solid Queue record with error message and backtrace.
• Structured Logging: Including job metadata in every log entry.

Real World Context

Order #4521 was never fulfilled. Find the failed job, understand why, fix and retry — or resolve manually.

Deep Dive

Structured Logging

ruby
class ApplicationJob < ActiveJob::Base
  around_perform do |job, block|
    Rails.logger.tagged("job:#{job.class.name}", "jid:#{job.job_id}") do
      Rails.logger.info "Starting: #{job.arguments.inspect}"
      block.call
      Rails.logger.info "Completed"
    end
  rescue => e
    Rails.logger.error "Failed: #{e.message}"
    raise
  end
end

Inspecting Failed Jobs (Solid Queue)

ruby
SolidQueue::FailedExecution.last(10).each do |fe|
  puts "#{fe.job.class_name}: #{fe.error['message']}"
  puts "Args: #{fe.job.arguments}"
end

# Retry a failed job
SolidQueue::FailedExecution.find(123).retry

# Retry all
SolidQueue::FailedExecution.find_each(&:retry)

Inspecting Failed Jobs (Sidekiq)

ruby
rs = Sidekiq::RetrySet.new
rs.each { |job| puts "#{job.klass}: #{job.error_message}" }

ds = Sidekiq::DeadSet.new
ds.each { |job| puts "#{job.klass}: #{job.error_message}" }

# Retry specific job
rs.find { |j| j.jid == 'abc123' }.retry

Common Pitfalls

1. Not logging job arguments — Can't reproduce without knowing the inputs.
2. Deleting failed jobs without investigation — They contain valuable debugging info.

Best Practices

1. Add structured logging to ApplicationJob.
2. Keep failed jobs for at least 7 days.

Summary

• Add structured logging for consistent, filterable output.
• Use SolidQueue::FailedExecution or Sidekiq::RetrySet to inspect failures.
• Retry individual or all failed jobs from the console.
• Keep failed jobs for investigation before discarding.

# Inspect and retry failed Solid Queue jobs
SolidQueue::FailedExecution.last(5).each do |fe|
  puts "#{fe.job.class_name}: #{fe.error['message']}"
end
SolidQueue::FailedExecution.find(42).retry