Update error handling and logging in message processing

- Modified the HandleMessage function to avoid logging actual message content and instead send generic error notices to clients for invalid or malformed messages, enhancing security by preventing exposure of binary data.
- Updated the NostrEscape function to escape all control characters to ensure valid JSON, preventing parsing errors with binary data.
- Adjusted policy checks to handle hex-encoded pubkeys correctly, ensuring compatibility with the updated encoding scheme.
- Introduced blackout period for relay connections after exceeding maximum reconnection delays, improving connection stability and management.

pkg/spider/spider.go

@@ -27,6 +27,8 @@ const (
 	ReconnectDelay = 5 * time.Second
 	// MaxReconnectDelay is the maximum delay between reconnection attempts
 	MaxReconnectDelay = 5 * time.Minute
+	// BlackoutPeriod is the duration to blacklist a relay after MaxReconnectDelay is reached
+	BlackoutPeriod = 24 * time.Hour
 )
 
 // Spider manages connections to admin relays and syncs events for followed pubkeys
@@ -64,8 +66,12 @@ type RelayConnection struct {
 	subscriptions map[string]*BatchSubscription
 
 	// Disconnection tracking
-	lastDisconnect time.Time
-	reconnectDelay time.Duration
+	lastDisconnect      time.Time
+	reconnectDelay      time.Duration
+	connectionStartTime time.Time
+
+	// Blackout tracking for IP filters
+	blackoutUntil time.Time
 }
 
 // BatchSubscription represents a subscription for a batch of pubkeys
@@ -261,6 +267,20 @@ func (rc *RelayConnection) manage(followList [][]byte) {
 		default:
 		}
 
+		// Check if relay is blacked out
+		if rc.isBlackedOut() {
+			log.D.F("spider: %s is blacked out until %v", rc.url, rc.blackoutUntil)
+			select {
+			case <-rc.ctx.Done():
+				return
+			case <-time.After(time.Until(rc.blackoutUntil)):
+				// Blackout expired, reset delay and try again
+				rc.reconnectDelay = ReconnectDelay
+				log.I.F("spider: blackout period ended for %s, retrying", rc.url)
+			}
+			continue
+		}
+
 		// Attempt to connect
 		if err := rc.connect(); chk.E(err) {
 			log.W.F("spider: failed to connect to %s: %v", rc.url, err)
@@ -269,7 +289,9 @@ func (rc *RelayConnection) manage(followList [][]byte) {
 		}
 
 		log.I.F("spider: connected to %s", rc.url)
+		rc.connectionStartTime = time.Now()
 		rc.reconnectDelay = ReconnectDelay // Reset delay on successful connection
+		rc.blackoutUntil = time.Time{}     // Clear blackout on successful connection
 
 		// Create subscriptions for follow list
 		rc.createSubscriptions(followList)
@@ -278,6 +300,19 @@ func (rc *RelayConnection) manage(followList [][]byte) {
 		<-rc.client.Context().Done()
 
 		log.W.F("spider: disconnected from %s: %v", rc.url, rc.client.ConnectionCause())
+		
+		// Check if disconnection happened very quickly (likely IP filter)
+		connectionDuration := time.Since(rc.connectionStartTime)
+		const quickDisconnectThreshold = 30 * time.Second
+		if connectionDuration < quickDisconnectThreshold {
+			log.W.F("spider: quick disconnection from %s after %v (likely IP filter)", rc.url, connectionDuration)
+			// Don't reset the delay, keep the backoff
+			rc.waitBeforeReconnect()
+		} else {
+			// Normal disconnection, reset backoff for future connections
+			rc.reconnectDelay = ReconnectDelay
+		}
+		
 		rc.handleDisconnection()
 
 		// Clean up
@@ -306,13 +341,21 @@ func (rc *RelayConnection) waitBeforeReconnect() {
 	case <-time.After(rc.reconnectDelay):
 	}
 
-	// Exponential backoff
+	// Exponential backoff - double every time
 	rc.reconnectDelay *= 2
-	if rc.reconnectDelay > MaxReconnectDelay {
-		rc.reconnectDelay = MaxReconnectDelay
+	
+	// If backoff exceeds 5 minutes, blackout for 24 hours
+	if rc.reconnectDelay >= MaxReconnectDelay {
+		rc.blackoutUntil = time.Now().Add(BlackoutPeriod)
+		log.W.F("spider: max backoff exceeded for %s (reached %v), blacking out for 24 hours", rc.url, rc.reconnectDelay)
 	}
 }
 
+// isBlackedOut returns true if the relay is currently blacked out
+func (rc *RelayConnection) isBlackedOut() bool {
+	return !rc.blackoutUntil.IsZero() && time.Now().Before(rc.blackoutUntil)
+}
+
 // handleDisconnection records disconnection time for catch-up logic
 func (rc *RelayConnection) handleDisconnection() {
 	now := time.Now()