Module: Quonfig::ForkSafety

Included in:
Quonfig
Defined in:
lib/quonfig/client.rb

Overview

qfg-ryov: hook into Process._fork so customers using Puma’s clustered mode (or any preload/fork-worker server) don’t have to wire before_fork/on_worker_boot manually. Ruby 3.1+ routes every Kernel#fork/Process.fork call through Process._fork, so a single prepend covers them all.

Process._fork’s contract:

- Called in the parent process before the fork syscall.
- Returns 0 in the child, child's pid in the parent.
- +super+ performs the actual fork.

The parent’s view: SSE/polling/telemetry threads are torn down before the syscall so the child does not inherit a live Net::HTTP socket fd (which would corrupt both sides). The parent does NOT auto-restart —that mirrors the Puma master use case where the master process no longer serves requests after spawning workers.

Instance Method Summary collapse

Instance Method Details

#_fork ⇒ Object 



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# File 'lib/quonfig/client.rb', line 1032

def _fork
  Quonfig::Client.each_instance(&:before_fork_in_parent)
  pid = super
  Quonfig::Client.each_instance(&:after_fork_in_child) if pid.zero?
  pid
rescue StandardError => e
  # Fork-hook failures must never break the customer's fork. Worst case
  # the child inherits dead SSE threads (the pre-qfg-ryov behavior) —
  # bad, but recoverable. Crashing the fork itself is not.
  Quonfig::Client::LOG.error "Quonfig fork hook error: #{e.class}: #{e.message}"
  raise if pid.nil? # super never returned — propagate fork failures

  pid
end