uplift gossip package from evm repositories

vms/evm/gossip/handler.go

@@ -0,0 +1,81 @@
+// Copyright (C) 2019-2025, Ava Labs, Inc. All rights reserved.
+// See the file LICENSE for licensing terms.
+
+package gossip
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+
+	"github.com/ava-labs/avalanchego/ids"
+	"github.com/ava-labs/avalanchego/network/p2p"
+	"github.com/ava-labs/avalanchego/network/p2p/gossip"
+	"github.com/ava-labs/avalanchego/snow/engine/common"
+	"github.com/ava-labs/avalanchego/utils/logging"
+)
+
+var _ p2p.Handler = (*txGossipHandler)(nil)
+
+type txGossipHandler struct {
+	appGossipHandler  p2p.Handler
+	appRequestHandler p2p.Handler
+}
+
+func NewTxGossipHandler[T gossip.Gossipable](
+	log logging.Logger,
+	marshaller gossip.Marshaller[T],
+	mempool gossip.Set[T],
+	metrics gossip.Metrics,
+	maxMessageSize int,
+	throttlingPeriod time.Duration,
+	requestsPerPeer float64,
+	validators p2p.ValidatorSet,
+	registerer prometheus.Registerer,
+	namespace string,
+) (p2p.Handler, error) {
+	// push gossip messages can be handled from any peer
+	handler := gossip.NewHandler(
+		log,
+		marshaller,
+		mempool,
+		metrics,
+		maxMessageSize,
+	)
+
+	throttledHandler, err := p2p.NewDynamicThrottlerHandler(
+		log,
+		handler,
+		validators,
+		throttlingPeriod,
+		requestsPerPeer,
+		registerer,
+		namespace,
+	)
+	if err != nil {
+		return nil, fmt.Errorf("failed to initialize throttler handler: %w", err)
+	}
+
+	// pull gossip requests are filtered by validators and are throttled
+	// to prevent spamming
+	validatorHandler := p2p.NewValidatorHandler(
+		throttledHandler,
+		validators,
+		log,
+	)
+
+	return &txGossipHandler{
+		appGossipHandler:  handler,
+		appRequestHandler: validatorHandler,
+	}, nil
+}
+
+func (t *txGossipHandler) AppGossip(ctx context.Context, nodeID ids.NodeID, gossipBytes []byte) {
+	t.appGossipHandler.AppGossip(ctx, nodeID, gossipBytes)
+}
+
+func (t *txGossipHandler) AppRequest(ctx context.Context, nodeID ids.NodeID, deadline time.Time, requestBytes []byte) ([]byte, *common.AppError) {
+	return t.appRequestHandler.AppRequest(ctx, nodeID, deadline, requestBytes)
+}