Remove header gossip from p2p module (cosmos#964)

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## Overview

Closes: cosmos#965 

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## Checklist

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- [x] New and updated code has appropriate documentation
- [x] New and updated code has new and/or updated testing
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Makefile

@@ -45,7 +45,7 @@ test-unit-race:
 	@go test -race -count=1 `go list ./...`
 .PHONY: test-unit-race
 
-### test-all: Run tests with and without data race
+## test-all: Run tests with and without data race
 test-all:
 	@$(MAKE) test-unit
 	@$(MAKE) test-unit-race

node/light.go

@@ -94,7 +94,6 @@ func newLightNode(
 	}
 
 	node.P2P.SetTxValidator(node.falseValidator())
-	node.P2P.SetHeaderValidator(node.falseValidator())
 
 	node.BaseService = *service.NewBaseService(logger, "LightNode", node)
 

p2p/client.go

@@ -38,9 +38,6 @@ const (
 
 	// txTopicSuffix is added after namespace to create pubsub topic for TX gossiping.
 	txTopicSuffix = "-tx"
-
-	// headerTopicSuffix is added after namespace to create pubsub topic for block header gossiping.
-	headerTopicSuffix = "-header"
 )
 
 // Client is a P2P client, implemented with libp2p.
@@ -62,9 +59,6 @@ type Client struct {
 	txGossiper  *Gossiper
 	txValidator GossipValidator
 
-	headerGossiper  *Gossiper
-	headerValidator GossipValidator
-
 	// cancel is used to cancel context passed to libp2p functions
 	// it's required because of discovery.Advertise call
 	cancel context.CancelFunc
@@ -156,7 +150,6 @@ func (c *Client) Close() error {
 
 	return multierr.Combine(
 		c.txGossiper.Close(),
-		c.headerGossiper.Close(),
 		c.dht.Close(),
 		c.host.Close(),
 	)
@@ -173,17 +166,6 @@ func (c *Client) SetTxValidator(val GossipValidator) {
 	c.txValidator = val
 }
 
-// GossipSignedHeader sends the block header to the P2P network.
-func (c *Client) GossipSignedHeader(ctx context.Context, headerBytes []byte) error {
-	c.logger.Debug("Gossiping block header", "len", len(headerBytes))
-	return c.headerGossiper.Publish(ctx, headerBytes)
-}
-
-// SetHeaderValidator sets the callback function, that will be invoked after block header is received from P2P network.
-func (c *Client) SetHeaderValidator(validator GossipValidator) {
-	c.headerValidator = validator
-}
-
 // Addrs returns listen addresses of Client.
 func (c *Client) Addrs() []multiaddr.Multiaddr {
 	return c.host.Addrs()
@@ -372,12 +354,6 @@ func (c *Client) setupGossiping(ctx context.Context) error {
 	}
 	go c.txGossiper.ProcessMessages(ctx)
 
-	c.headerGossiper, err = NewGossiper(c.host, c.ps, c.getHeaderTopic(), c.logger, WithValidator(c.headerValidator))
-	if err != nil {
-		return err
-	}
-	go c.headerGossiper.ProcessMessages(ctx)
-
 	return nil
 }
 
@@ -415,7 +391,3 @@ func (c *Client) getNamespace() string {
 func (c *Client) getTxTopic() string {
 	return c.getNamespace() + txTopicSuffix
 }
-
-func (c *Client) getHeaderTopic() string {
-	return c.getNamespace() + headerTopicSuffix
-}