Struct processSupervisor

pkg/gotenberg/supervisor.go:106–138

const healthFailureThreshold = 2

type processSupervisor struct {
	logger         *slog.Logger
	engine         string
	process        Process
	maxReqLimit    int64
	maxQueueSize   int64
	maxConcurrency int64
	semaphore      chan struct{}
	firstStart     atomic.Bool
	// firstStartMu serializes lazy-launch attempts so concurrent callers do
	// not all spawn Launch() simultaneously. Using a mutex (instead of
	// sync.Once) lets a failed launch be retried by the next caller, since a
	// transient failure (such as a cold-start timeout) must not poison the
	// supervisor for the rest of the container's lifetime. See
	// https://github.com/gotenberg/gotenberg/issues/1538.
	firstStartMu        sync.Mutex
	reqCounter          atomic.Int64
	reqQueueSize        atomic.Int64
	restartsCounter     atomic.Int64
	isRestarting        atomic.Bool
	activeTasks         atomic.Int64
	restartMutex        sync.Mutex
	idleShutdownTimeout time.Duration
	lastActivity        atomic.Int64 // unix nano timestamp of last completed task
	// healthMu serializes Healthy() probes so concurrent callers do not
	// all issue a CDP roundtrip; the second caller hits the refreshed
	// cache instead.
	healthMu                  sync.Mutex
	lastHealthyAt             atomic.Int64  // unix nano of last successful probe; 0 means never
	consecutiveHealthFailures atomic.Int64  // reset to 0 on every successful probe
	idleMu                    sync.Mutex    // protects idleStopChan
	idleStopChan              chan struct{} // signal to stop the idle ticker goroutine
}

// NewProcessSupervisor initializes a new [ProcessSupervisor]. engine names the
// managed process (for example "chromium" or "libreoffice") and prefixes the