Struct Batcher

coderd/agentapi/metadatabatcher/metadata_batcher.go:77–103

Batcher holds a buffer of agent metadata updates and periodically flushes them to the database and pubsub. This reduces database write frequency and pubsub publish rate.

// flushes them to the database and pubsub. This reduces database write
// frequency and pubsub publish rate.
type Batcher struct {
	store database.Store
	ps    pubsub.Pubsub
	log   slog.Logger

	// updateCh is the buffered channel that receives metadata updates from Add() calls.
	updateCh chan update

	// batch holds the current batch being accumulated. For updates with the same composite key the most recent value wins.
	batch           map[compositeKey]value
	currentBatchLen atomic.Int64
	maxBatchSize    int

	clock    quartz.Clock
	timer    *quartz.Timer
	interval time.Duration
	// Used to only log at warn level for dropped keys infrequently, as it could be noisy in failure scenarios.
	warnTicker *quartz.Ticker

	// ctx is the context for the batcher. Used to check if shutdown has begun.
	ctx    context.Context
	cancel context.CancelFunc
	done   chan struct{}

	// Metrics collects Prometheus metrics for the batcher.
	Metrics Metrics
}

// Option is a functional option for configuring a Batcher.
type Option func(b *Batcher)