add metrics for caching

tools/walletextension/cache/RistrettoCache.go

@@ -1,6 +1,7 @@
 package cache
 
 import (
+	"github.com/ethereum/go-ethereum/log"
 	"time"
 
 	"github.com/dgraph-io/ristretto"
@@ -15,10 +16,11 @@ const (
 
 type RistrettoCache struct {
 	cache *ristretto.Cache
+	quit  chan struct{}
 }
 
 // NewRistrettoCache returns a new RistrettoCache.
-func NewRistrettoCache() (*RistrettoCache, error) {
+func NewRistrettoCache(logger log.Logger) (*RistrettoCache, error) {
 	cache, err := ristretto.NewCache(&ristretto.Config{
 		NumCounters: numCounters,
 		MaxCost:     maxCost,
@@ -28,7 +30,16 @@ func NewRistrettoCache() (*RistrettoCache, error) {
 	if err != nil {
 		return nil, err
 	}
-	return &RistrettoCache{cache}, nil
+
+	c := &RistrettoCache{
+		cache: cache,
+		quit:  make(chan struct{}),
+	}
+
+	// Start the metrics logging
+	go c.startMetricsLogging(logger)
+
+	return c, nil
 }
 
 // Set adds the key and value to the cache.
@@ -52,3 +63,19 @@ func (c *RistrettoCache) Get(key string) (value map[string]interface{}, ok bool)
 
 	return value, true
 }
+
+// startMetricsLogging starts logging cache metrics every hour.
+func (c *RistrettoCache) startMetricsLogging(logger log.Logger) {
+	ticker := time.NewTicker(1 * time.Hour)
+	for {
+		select {
+		case <-ticker.C:
+			metrics := c.cache.Metrics
+			logger.Info("Cache metrics: Hits: %d, Misses: %d, Cost Added: %d\n",
+				metrics.Hits(), metrics.Misses(), metrics.CostAdded())
+		case <-c.quit:
+			ticker.Stop()
+			return
+		}
+	}
+}

tools/walletextension/cache/cache.go

@@ -4,6 +4,7 @@ import (
 	"crypto/sha256"
 	"encoding/json"
 	"fmt"
+	"github.com/ethereum/go-ethereum/log"
 	"time"
 
 	"github.com/ten-protocol/go-ten/tools/walletextension/common"
@@ -39,8 +40,8 @@ type Cache interface {
 	Get(key string) (value map[string]interface{}, ok bool)
 }
 
-func NewCache() (Cache, error) {
-	return NewRistrettoCache() // TODO: Fix signatures..
+func NewCache(logger log.Logger) (Cache, error) {
+	return NewRistrettoCache(logger)
 }
 
 // IsCacheable checks if the given RPC request is cacheable and returns the cache key and TTL

tools/walletextension/wallet_extension.go

@@ -65,7 +65,7 @@ func New(
 	}
 	newTenClient := obsclient.NewObsClient(rpcClient)
 	newFileLogger := common.NewFileLogger()
-	newGatewayCache, err := cache.NewCache()
+	newGatewayCache, err := cache.NewCache(logger)
 	if err != nil {
 		logger.Error(fmt.Errorf("could not create cache. Cause: %w", err).Error())
 		panic(err)