don't use cache (overkill)

internal/api/model/instance.go

@@ -17,7 +17,10 @@
 
 package model
 
-import "mime/multipart"
+import (
+	"mime/multipart"
+	"time"
+)
 
 // InstanceSettingsUpdateRequest models an instance update request.
 //
@@ -154,4 +157,5 @@ type RandomStats struct {
 	Statuses           int64
 	TotalUsers         int64
 	MonthlyActiveUsers int64
+	Generated          time.Time
 }

internal/typeutils/converter.go

@@ -22,11 +22,10 @@ import (
 	"math/big"
 	"math/rand"
 	"sync"
+	"sync/atomic"
 	"time"
 
-	"codeberg.org/gruf/go-cache/v3"
 	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
-	"github.com/superseriousbusiness/gotosocial/internal/config"
 	"github.com/superseriousbusiness/gotosocial/internal/filter/interaction"
 	"github.com/superseriousbusiness/gotosocial/internal/filter/visibility"
 	"github.com/superseriousbusiness/gotosocial/internal/log"
@@ -39,64 +38,64 @@ type Converter struct {
 	randAvatars    sync.Map
 	visFilter      *visibility.Filter
 	intFilter      *interaction.Filter
-	randStatsCache cache.TTLCache[struct{}, apimodel.RandomStats]
+	randStats      atomic.Pointer[apimodel.RandomStats]
 }
 
 func NewConverter(state *state.State) *Converter {
-	// If randomizing instance stats, create a cache so we
-	// don't have to generate them every time, and set a 1hr
-	// ttl on the cache so they're not always the same.
-	var randStatsCache cache.TTLCache[struct{}, apimodel.RandomStats]
-	if config.GetInstanceStatsRandomize() {
-		randStatsCache = cache.NewTTL[struct{}, apimodel.RandomStats](0, 1, 0)
-		randStatsCache.SetTTL(time.Hour, false)
-		if !randStatsCache.Start(time.Minute) {
-			log.Panicf(nil, "couldn't start randStatsCache")
-		}
-	}
-
 	return &Converter{
 		state:          state,
 		defaultAvatars: populateDefaultAvatars(),
 		visFilter:      visibility.NewFilter(state),
 		intFilter:      interaction.NewFilter(state),
-		randStatsCache: randStatsCache,
 	}
 }
 
 // RandomStats returns or generates
 // and returns random instance stats.
 func (c *Converter) RandomStats() apimodel.RandomStats {
+	now := time.Now()
+	stats := c.randStats.Load()
+	if stats != nil && time.Since(stats.Generated) < time.Hour {
+		// Random stats are still
+		// fresh (less than 1hr old),
+		// so return them as-is.
+		return *stats
+	}
+
+	// Generate new random stats.
+	newStats := genRandStats()
+	newStats.Generated = now
+	c.randStats.Store(&newStats)
+	return newStats
+}
+
+func genRandStats() apimodel.RandomStats {
 	const (
 		statusesMax = 10000000
 		usersMax    = 1000000
 	)
 
-	stats, ok := c.randStatsCache.Get(struct{}{})
-	if !ok {
-		statusesB, err := crand.Int(crand.Reader, big.NewInt(statusesMax))
-		if err != nil {
-			// Only errs if something is buggered with the OS.
-			log.Panicf(nil, "error randomly generating statuses count: %v", err)
-		}
-
-		totalUsersB, err := crand.Int(crand.Reader, big.NewInt(usersMax))
-		if err != nil {
-			// Only errs if something is buggered with the OS.
-			log.Panicf(nil, "error randomly generating users count: %v", err)
-		}
-
-		totalUsers := totalUsersB.Int64()
-		activeRatio := rand.Float64() //nolint
-		mau := int64(float64(totalUsers) * activeRatio)
-
-		stats = apimodel.RandomStats{
-			Statuses:           statusesB.Int64(),
-			TotalUsers:         totalUsers,
-			MonthlyActiveUsers: mau,
-		}
-		c.randStatsCache.Set(struct{}{}, stats)
+	statusesB, err := crand.Int(crand.Reader, big.NewInt(statusesMax))
+	if err != nil {
+		// Only errs if something is buggered with the OS.
+		log.Panicf(nil, "error randomly generating statuses count: %v", err)
 	}
 
-	return stats
+	totalUsersB, err := crand.Int(crand.Reader, big.NewInt(usersMax))
+	if err != nil {
+		// Only errs if something is buggered with the OS.
+		log.Panicf(nil, "error randomly generating users count: %v", err)
+	}
+
+	// Monthly users should only ever
+	// be <= 100% of total users.
+	totalUsers := totalUsersB.Int64()
+	activeRatio := rand.Float64() //nolint
+	mau := int64(float64(totalUsers) * activeRatio)
+
+	return apimodel.RandomStats{
+		Statuses:           statusesB.Int64(),
+		TotalUsers:         totalUsers,
+		MonthlyActiveUsers: mau,
+	}
 }