feat: put/get artificial latency for memstore backend

cmd/server/entrypoint.go

@@ -13,9 +13,6 @@ import (
 )
 
 func StartProxySvr(cliCtx *cli.Context) error {
-	if err := server.CheckRequired(cliCtx); err != nil {
-		return err
-	}
 	cfg := server.ReadCLIConfig(cliCtx)
 	if err := cfg.Check(); err != nil {
 		return err

server/config.go

@@ -38,6 +38,8 @@ const (
 	// memstore flags
 	MemstoreFlagName           = "memstore.enabled"
 	MemstoreExpirationFlagName = "memstore.expiration"
+	MemstorePutLatencyFlagName = "memstore.put-latency"
+	MemstoreGetLatencyFlagName = "memstore.get-latency"
 
 	// S3 client flags
 	S3CredentialTypeFlagName  = "s3.credential-type" // #nosec G101
@@ -90,6 +92,8 @@ type Config struct {
 	// Memstore
 	MemstoreEnabled        bool
 	MemstoreBlobExpiration time.Duration
+	MemstoreGetLatency     time.Duration
+	MemstorePutLatency     time.Duration
 
 	// routing
 	FallbackTargets []string
@@ -179,6 +183,8 @@ func ReadConfig(ctx *cli.Context) Config {
 		EthConfirmationDepth:   ctx.Int64(EthConfirmationDepthFlagName),
 		MemstoreEnabled:        ctx.Bool(MemstoreFlagName),
 		MemstoreBlobExpiration: ctx.Duration(MemstoreExpirationFlagName),
+		MemstoreGetLatency:     ctx.Duration(MemstoreGetLatencyFlagName),
+		MemstorePutLatency:     ctx.Duration(MemstorePutLatencyFlagName),
 		FallbackTargets:        ctx.StringSlice(FallbackTargets),
 		CacheTargets:           ctx.StringSlice(CacheTargets),
 	}
@@ -419,6 +425,18 @@ func CLIFlags() []cli.Flag {
 			Value:   25 * time.Minute,
 			EnvVars: []string{"MEMSTORE_EXPIRATION"},
 		},
+		&cli.DurationFlag{
+			Name:    MemstorePutLatencyFlagName,
+			Usage:   "Artificial latency added for memstore backend to mimic EigenDA's dispersal latency.",
+			Value:   0,
+			EnvVars: []string{"MEMSTORE_PUT_LATENCY"},
+		},
+		&cli.DurationFlag{
+			Name:    MemstoreGetLatencyFlagName,
+			Usage:   "Artificial latency added for memstore backend to mimic EigenDA's retrieval latency.",
+			Value:   0,
+			EnvVars: []string{"MEMSTORE_GET_LATENCY"},
+		},
 		&cli.StringSliceFlag{
 			Name:    FallbackTargets,
 			Usage:   "List of read fallback targets to rollover to if cert can't be read from EigenDA.",

server/load_store.go

@@ -47,7 +47,7 @@ func LoadStoreRouter(ctx context.Context, cfg CLIConfig, log log.Logger) (store.
 	var eigenda store.KeyGeneratedStore
 	if cfg.EigenDAConfig.MemstoreEnabled {
 		log.Info("Using mem-store backend for EigenDA")
-		eigenda, err = store.NewMemStore(ctx, verifier, log, maxBlobLength, cfg.EigenDAConfig.MemstoreBlobExpiration)
+		eigenda, err = store.NewMemStore(ctx, verifier, log, maxBlobLength, cfg.EigenDAConfig.MemstoreBlobExpiration, cfg.EigenDAConfig.MemstorePutLatency, cfg.EigenDAConfig.MemstoreGetLatency)
 	} else {
 		var client *clients.EigenDAClient
 		log.Info("Using EigenDA backend")

store/memory.go

@@ -30,11 +30,13 @@ EigenDA operators.
 type MemStore struct {
 	sync.RWMutex
 
-	l         log.Logger
-	keyStarts map[string]time.Time
-	store     map[string][]byte
-	verifier  *verify.Verifier
-	codec     codecs.BlobCodec
+	l          log.Logger
+	keyStarts  map[string]time.Time
+	store      map[string][]byte
+	verifier   *verify.Verifier
+	codec      codecs.BlobCodec
+	putLatency time.Duration
+	getLatency time.Duration
 
 	maxBlobSizeBytes uint64
 	blobExpiration   time.Duration
@@ -45,7 +47,8 @@ var _ KeyGeneratedStore = (*MemStore)(nil)
 
 // NewMemStore ... constructor
 func NewMemStore(ctx context.Context, verifier *verify.Verifier, l log.Logger,
-	maxBlobSizeBytes uint64, blobExpiration time.Duration) (*MemStore, error) {
+	maxBlobSizeBytes uint64, blobExpiration time.Duration,
+	putLatency, getLatency time.Duration) (*MemStore, error) {
 	store := &MemStore{
 		l:                l,
 		keyStarts:        make(map[string]time.Time),
@@ -54,6 +57,9 @@ func NewMemStore(ctx context.Context, verifier *verify.Verifier, l log.Logger,
 		codec:            codecs.NewIFFTCodec(codecs.NewDefaultBlobCodec()),
 		maxBlobSizeBytes: maxBlobSizeBytes,
 		blobExpiration:   blobExpiration,
+		// artificial latency added for memstore backend to mimic eigenda's latency
+		putLatency:       putLatency,
+		getLatency:       getLatency,
 	}
 
 	if store.blobExpiration != 0 {
@@ -97,6 +103,7 @@ func (e *MemStore) pruneExpired() {
 
 // Get fetches a value from the store.
 func (e *MemStore) Get(_ context.Context, commit []byte) ([]byte, error) {
+	time.Sleep(e.getLatency)
 	e.reads++
 	e.RLock()
 	defer e.RUnlock()
@@ -124,6 +131,7 @@ func (e *MemStore) Get(_ context.Context, commit []byte) ([]byte, error) {
 
 // Put inserts a value into the store.
 func (e *MemStore) Put(_ context.Context, value []byte) ([]byte, error) {
+	time.Sleep(e.putLatency)
 	if uint64(len(value)) > e.maxBlobSizeBytes {
 		return nil, fmt.Errorf("blob is larger than max blob size: blob length %d, max blob size %d", len(value), e.maxBlobSizeBytes)
 	}

store/memory_test.go

@@ -43,6 +43,7 @@ func TestGetSet(t *testing.T) {
 		log.New(),
 		1024*1024*2,
 		time.Hour*1000,
+		0, 0,
 	)
 
 	require.NoError(t, err)
@@ -85,6 +86,7 @@ func TestExpiration(t *testing.T) {
 		log.New(),
 		1024*1024*2,
 		time.Millisecond*10,
+		0, 0,
 	)
 
 	require.NoError(t, err)
@@ -100,3 +102,56 @@ func TestExpiration(t *testing.T) {
 	require.Error(t, err)
 
 }
+
+func TestLatency(t *testing.T) {
+	t.Parallel()
+
+	putLatency := 1 * time.Second
+	getLatency := 1 * time.Second
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	kzgConfig := &kzg.KzgConfig{
+		G1Path:          "../resources/g1.point",
+		G2PowerOf2Path:  "../resources/g2.point.powerOf2",
+		CacheDir:        "../resources/SRSTables",
+		SRSOrder:        3000,
+		SRSNumberToLoad: 3000,
+		NumWorker:       uint64(runtime.GOMAXPROCS(0)),
+	}
+
+	cfg := &verify.Config{
+		Verify:    false,
+		KzgConfig: kzgConfig,
+	}
+
+	verifier, err := verify.NewVerifier(cfg, nil)
+	require.NoError(t, err)
+
+	ms, err := NewMemStore(
+		ctx,
+		verifier,
+		log.New(),
+		1024*1024*2,
+		time.Millisecond*10,
+		putLatency, getLatency,
+	)
+
+	require.NoError(t, err)
+
+	preimage := []byte(testPreimage)
+	timeBeforePut := time.Now()
+	key, err := ms.Put(ctx, preimage)
+	require.NoError(t, err)
+	require.GreaterOrEqual(t, time.Since(timeBeforePut), putLatency)
+
+	// sleep 1 second and verify that older blob entries are removed
+	time.Sleep(time.Second * 1)
+
+	timeBeforeGet := time.Now()
+	_, err = ms.Get(ctx, key)
+	require.Error(t, err)
+	require.GreaterOrEqual(t, time.Since(timeBeforeGet), getLatency)
+
+}