feat: add env var for recently connected ttl

cached_addr_book.go

@@ -25,8 +25,9 @@ import (
 
 const (
 	Subsystem = "cached_addr_book"
-	// The TTL to keep recently connected peers for. Same as [amino.DefaultProvideValidity] in go-libp2p-kad-dht
-	RecentlyConnectedAddrTTL = amino.DefaultProvideValidity
+
+	// The default TTL to keep recently connected peers' multiaddrs for
+	DefaultRecentlyConnectedAddrTTL = amino.DefaultProvideValidity
 
 	// Connected peers don't expire until they disconnect
 	ConnectedAddrTTL = peerstore.ConnectedAddrTTL
@@ -48,8 +49,9 @@ const (
 	// 1_000_000 is 10x the default number of signed peer records cached by the memory address book.
 	PeerCacheSize = 1_000_000
 
-	// Maximum backoff duration for probing a peer
-	MaxBackoffDuration = time.Hour * 48
+	// Maximum backoff duration for probing a peer. After this duration, we will stop
+	// trying to connect to the peer and remove it from the cache.
+	MaxBackoffDuration = amino.DefaultProvideValidity
 )
 
 var (
@@ -84,10 +86,11 @@ type peerState struct {
 }
 
 type cachedAddrBook struct {
-	addrBook        peerstore.AddrBook             // memory address book
-	peerCache       *lru.Cache[peer.ID, peerState] // LRU cache with additional metadata about peer
-	isProbing       atomic.Bool
-	allowPrivateIPs bool // for testing
+	addrBook             peerstore.AddrBook             // memory address book
+	peerCache            *lru.Cache[peer.ID, peerState] // LRU cache with additional metadata about peer
+	isProbing            atomic.Bool
+	allowPrivateIPs      bool // for testing
+	recentlyConnectedTTL time.Duration
 }
 
 type AddrBookOption func(*cachedAddrBook) error
@@ -99,15 +102,23 @@ func WithAllowPrivateIPs() AddrBookOption {
 	}
 }
 
+func WithRecentlyConnectedTTL(ttl time.Duration) AddrBookOption {
+	return func(cab *cachedAddrBook) error {
+		cab.recentlyConnectedTTL = ttl
+		return nil
+	}
+}
+
 func newCachedAddrBook(opts ...AddrBookOption) (*cachedAddrBook, error) {
 	peerCache, err := lru.New[peer.ID, peerState](PeerCacheSize)
 	if err != nil {
 		return nil, err
 	}
 
 	cab := &cachedAddrBook{
-		peerCache: peerCache,
-		addrBook:  pstoremem.NewAddrBook(),
+		peerCache:            peerCache,
+		addrBook:             pstoremem.NewAddrBook(),
+		recentlyConnectedTTL: DefaultRecentlyConnectedAddrTTL, // Set default value
 	}
 
 	for _, opt := range opts {
@@ -116,6 +127,7 @@ func newCachedAddrBook(opts ...AddrBookOption) (*cachedAddrBook, error) {
 			return nil, err
 		}
 	}
+	logger.Infof("cachedAddrBook: Using TTL of %s for recently connected peers", cab.recentlyConnectedTTL)
 	return cab, nil
 }
 
@@ -157,7 +169,7 @@ func (cab *cachedAddrBook) background(ctx context.Context, host host.Host) {
 				cab.peerCache.Add(ev.Peer, pState)
 				peerStateSize.Set(float64(cab.peerCache.Len())) // update metric
 
-				ttl := getTTL(host.Network().Connectedness(ev.Peer))
+				ttl := cab.getTTL(host.Network().Connectedness(ev.Peer))
 				if ev.SignedPeerRecord != nil {
 					logger.Debug("Caching signed peer record")
 					cab, ok := peerstore.GetCertifiedAddrBook(cab.addrBook)
@@ -175,7 +187,7 @@ func (cab *cachedAddrBook) background(ctx context.Context, host host.Host) {
 			case event.EvtPeerConnectednessChanged:
 				// If the peer is not connected or limited, we update the TTL
 				if !hasValidConnectedness(ev.Connectedness) {
-					cab.addrBook.UpdateAddrs(ev.Peer, ConnectedAddrTTL, RecentlyConnectedAddrTTL)
+					cab.addrBook.UpdateAddrs(ev.Peer, ConnectedAddrTTL, cab.recentlyConnectedTTL)
 				}
 			}
 		case <-probeTicker.C:
@@ -313,9 +325,9 @@ func hasValidConnectedness(connectedness network.Connectedness) bool {
 	return connectedness == network.Connected || connectedness == network.Limited
 }
 
-func getTTL(connectedness network.Connectedness) time.Duration {
+func (cab *cachedAddrBook) getTTL(connectedness network.Connectedness) time.Duration {
 	if hasValidConnectedness(connectedness) {
 		return ConnectedAddrTTL
 	}
-	return RecentlyConnectedAddrTTL
+	return cab.recentlyConnectedTTL
 }

docs/environment-variables.md

@@ -37,6 +37,18 @@ Whether or not the Accelerated DHT is enabled or not.
 
 Default: `true`
 
+### `SOMEGUY_CACHED_ADDR_BOOK`
+
+Whether or not the Cached Address Book is enabled or not.
+
+Default: `true`
+
+### `SOMEGUY_CACHED_ADDR_BOOK_RECENT_TTL`
+
+The TTL for recently connected peers' multiaddrs in the cached address book.
+
+Default: `48h`
+
 ### `SOMEGUY_PROVIDER_ENDPOINTS`
 
 Comma-separated list of other Delegated Routing V1 endpoints to proxy provider requests to.

main.go

@@ -44,6 +44,13 @@ func main() {
 						EnvVars: []string{"SOMEGUY_CACHED_ADDR_BOOK"},
 						Usage:   "use a cached address book to improve provider lookup responses",
 					},
+					&cli.DurationFlag{
+						Name:        "cached-addr-book-recent-ttl",
+						DefaultText: DefaultRecentlyConnectedAddrTTL.String(),
+						Value:       DefaultRecentlyConnectedAddrTTL,
+						EnvVars:     []string{"SOMEGUY_CACHED_ADDR_BOOK_RECENT_TTL"},
+						Usage:       "TTL for recently connected peers' multiaddrs in the cached address book",
+					},
 					&cli.StringSliceFlag{
 						Name:    "provider-endpoints",
 						Value:   cli.NewStringSlice(cidContactEndpoint),
@@ -121,9 +128,10 @@ func main() {
 				},
 				Action: func(ctx *cli.Context) error {
 					cfg := &config{
-						listenAddress:        ctx.String("listen-address"),
-						acceleratedDHTClient: ctx.Bool("accelerated-dht"),
-						cachedAddrBook:       ctx.Bool("cached-addr-book"),
+						listenAddress:           ctx.String("listen-address"),
+						acceleratedDHTClient:    ctx.Bool("accelerated-dht"),
+						cachedAddrBook:          ctx.Bool("cached-addr-book"),
+						cachedAddrBookRecentTTL: ctx.Duration("cached-addr-book-recent-ttl"),
 
 						contentEndpoints: ctx.StringSlice("provider-endpoints"),
 						peerEndpoints:    ctx.StringSlice("peer-endpoints"),

server.go

@@ -40,9 +40,10 @@ func withRequestLogger(next http.Handler) http.Handler {
 }
 
 type config struct {
-	listenAddress        string
-	acceleratedDHTClient bool
-	cachedAddrBook       bool
+	listenAddress           string
+	acceleratedDHTClient    bool
+	cachedAddrBook          bool
+	cachedAddrBookRecentTTL time.Duration
 
 	contentEndpoints []string
 	peerEndpoints    []string
@@ -85,7 +86,13 @@ func start(ctx context.Context, cfg *config) error {
 
 	if cfg.cachedAddrBook {
 		fmt.Println("Using cached address book to speed up provider discovery")
-		cachedAddrBook, err = newCachedAddrBook()
+		opts := []AddrBookOption{}
+
+		if cfg.cachedAddrBookRecentTTL > 0 {
+			opts = append(opts, WithRecentlyConnectedTTL(cfg.cachedAddrBookRecentTTL))
+		}
+
+		cachedAddrBook, err = newCachedAddrBook(opts...)
 		if err != nil {
 			return err
 		}