Class: Findbug::BackgroundPersister

Inherits:
Object
  • Object
show all
Defined in:
lib/findbug/background_persister.rb

Overview

BackgroundPersister runs a background thread that periodically moves events from the Redis buffer to the database.

WHY A BACKGROUND THREAD?

We want Findbug to work “out of the box” without requiring users to:

  1. Set up Sidekiq/ActiveJob

  2. Configure recurring jobs

  3. Run separate worker processes

A background thread achieves this by running inside the Rails process.

THREAD SAFETY

  • Uses Mutex for start/stop synchronization

  • Only one persister thread runs at a time

  • Safe to call start! multiple times (idempotent)

GRACEFUL SHUTDOWN

The thread checks a @running flag and exits cleanly when stopped. We also register an at_exit hook to ensure cleanup.

LIMITATIONS

  • Only persists in the process where it’s started

  • In multi-process setups (Puma cluster), each process has its own thread

  • For high-volume apps, users should use the ActiveJob approach instead

Constant Summary collapse

DEFAULT_INTERVAL =

seconds

30

Class Method Summary collapse

Class Method Details

.persist_now! ⇒ Object

Force an immediate persist (useful for testing)



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# File 'lib/findbug/background_persister.rb', line 75

def persist_now!
  perform_persist
end

.running? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/findbug/background_persister.rb', line 70

def running?
  @running == true && @thread&.alive?
end

.start!(interval: nil) ⇒ Object 



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# File 'lib/findbug/background_persister.rb', line 41

def start!(interval: nil)
  return if @running

  @mutex ||= Mutex.new
  @mutex.synchronize do
    return if @running

    @interval = interval || Findbug.config.persist_interval || DEFAULT_INTERVAL
    @running = true
    @thread = Thread.new { run_loop }
    @thread.name = "findbug-persister"
    @thread.abort_on_exception = false

    Findbug.logger.info("[Findbug] Background persister started (interval: #{@interval}s)")
  end
end

.stop! ⇒ Object 



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# File 'lib/findbug/background_persister.rb', line 58

def stop!
  return unless @running

  @mutex.synchronize do
    @running = false
    @thread&.wakeup rescue nil # Wake from sleep
    @thread&.join(5) # Wait up to 5 seconds
    @thread = nil
    Findbug.logger.info("[Findbug] Background persister stopped")
  end
end