chore(pgs): log key eviction

Commit `9baad06`

Eric Bower · 2026-04-19 13:39:58 -0400 EDT

parent 1e1cc0b

chore(pgs): log key eviction

1 files changed, +5, -2

M pkg/apps/pgs/web.go

+5, -2

......@@ -44,6 +44,7 @@ func (c *PgsCacheKey) GetCacheKey(r *http.Request) string {
}

type PromCacheMetrics struct {
	Logger         *slog.Logger
	Cache          httpcache.Cacher
	CacheItems     prometheus.Gauge
	CacheSizeBytes prometheus.Gauge

......@@ -52,10 +53,11 @@ type PromCacheMetrics struct {
	UpstreamReq    prometheus.Counter
}

func NewPromCacheMetrics(reg prometheus.Registerer) *PromCacheMetrics {
func NewPromCacheMetrics(logger *slog.Logger, reg prometheus.Registerer) *PromCacheMetrics {
	name := "pgs"
	auto := promauto.With(reg)
	return &PromCacheMetrics{
		Logger: logger,
		CacheItems: auto.NewGauge(prometheus.GaugeOpts{
			Namespace: name,
			Subsystem: "http_cache",

......@@ -93,6 +95,7 @@ func (p *PromCacheMetrics) AddCacheItem(size float64) {
	p.CacheSizeBytes.Add(size)
}
func (p *PromCacheMetrics) EvictCacheItem(key string, value []byte) {
	p.Logger.Info("evicting cache key", "key", key, "len_bytes", len(value))
	p.CacheItems.Add(-1)
	p.CacheSizeBytes.Add(-float64(len(value)))
}

......@@ -108,7 +111,7 @@ func (p *PromCacheMetrics) AddUpstreamRequest() {

func NewPgsHttpCache(cfg *PgsConfig, upstream http.Handler) *httpcache.HttpCache {
	ttl := cfg.CacheTTL
	metrics := NewPromCacheMetrics(prometheus.DefaultRegisterer)
	metrics := NewPromCacheMetrics(cfg.Logger, prometheus.DefaultRegisterer)
	cache := expirable.NewLRU(0, metrics.EvictCacheItem, ttl)
	httpCache := &httpcache.HttpCache{
		Ttl:      ttl,

...	...		@@ -44,6 +44,7 @@ func (c PgsCacheKey) GetCacheKey(r http.Request) string {
44	44		}
45	45
46	46		type PromCacheMetrics struct {
	47	+	Logger *slog.Logger
47	48		Cache httpcache.Cacher
48	49		CacheItems prometheus.Gauge
49	50		CacheSizeBytes prometheus.Gauge

...	...		@@ -52,10 +53,11 @@ type PromCacheMetrics struct {
52	53		UpstreamReq prometheus.Counter
53	54		}
54	55
55		-	func NewPromCacheMetrics(reg prometheus.Registerer) *PromCacheMetrics {
	56	+	func NewPromCacheMetrics(logger slog.Logger, reg prometheus.Registerer) PromCacheMetrics {
56	57		name := "pgs"
57	58		auto := promauto.With(reg)
58	59		return &PromCacheMetrics{
	60	+	Logger: logger,
59	61		CacheItems: auto.NewGauge(prometheus.GaugeOpts{
60	62		Namespace: name,
61	63		Subsystem: "http_cache",

...	...		@@ -93,6 +95,7 @@ func (p *PromCacheMetrics) AddCacheItem(size float64) {
93	95		p.CacheSizeBytes.Add(size)
94	96		}
95	97		func (p *PromCacheMetrics) EvictCacheItem(key string, value []byte) {
	98	+	p.Logger.Info("evicting cache key", "key", key, "len_bytes", len(value))
96	99		p.CacheItems.Add(-1)
97	100		p.CacheSizeBytes.Add(-float64(len(value)))
98	101		}

...	...		@@ -108,7 +111,7 @@ func (p *PromCacheMetrics) AddUpstreamRequest() {
108	111
109	112		func NewPgsHttpCache(cfg PgsConfig, upstream http.Handler) httpcache.HttpCache {
110	113		ttl := cfg.CacheTTL
111		-	metrics := NewPromCacheMetrics(prometheus.DefaultRegisterer)
	114	+	metrics := NewPromCacheMetrics(cfg.Logger, prometheus.DefaultRegisterer)
112	115		cache := expirable.NewLRU(0, metrics.EvictCacheItem, ttl)
113	116		httpCache := &httpcache.HttpCache{
114	117		Ttl: ttl,

Commit 9baad06

Commit `9baad06`