light: CHT and bloom trie indexers working in light mode (#16534)

This PR enables the indexers to work in light client mode by
downloading a part of these tries (the Merkle proofs of the last
values of the last known section) in order to be able to add new
values and recalculate subsequent hashes. It also adds CHT data to
NodeInfo.

1 files changed, 21 insertions, 18 deletions

diff --git a/les/backend.go b/les/backend.go
index 178bc1e0e..9b8cc1828 100644
--- a/les/backend.go
+++ b/les/backend.go
@@ -95,29 +95,35 @@ func New(ctx *node.ServiceContext, config *eth.Config) (*LightEthereum, error) {
 	quitSync := make(chan struct{})
 
 	leth := &LightEthereum{
-		config:           config,
-		chainConfig:      chainConfig,
-		chainDb:          chainDb,
-		eventMux:         ctx.EventMux,
-		peers:            peers,
-		reqDist:          newRequestDistributor(peers, quitSync),
-		accountManager:   ctx.AccountManager,
-		engine:           eth.CreateConsensusEngine(ctx, chainConfig, &config.Ethash, nil, chainDb),
-		shutdownChan:     make(chan bool),
-		networkId:        config.NetworkId,
-		bloomRequests:    make(chan chan *bloombits.Retrieval),
-		bloomIndexer:     eth.NewBloomIndexer(chainDb, light.BloomTrieFrequency),
-		chtIndexer:       light.NewChtIndexer(chainDb, true),
-		bloomTrieIndexer: light.NewBloomTrieIndexer(chainDb, true),
+		config:         config,
+		chainConfig:    chainConfig,
+		chainDb:        chainDb,
+		eventMux:       ctx.EventMux,
+		peers:          peers,
+		reqDist:        newRequestDistributor(peers, quitSync),
+		accountManager: ctx.AccountManager,
+		engine:         eth.CreateConsensusEngine(ctx, chainConfig, &config.Ethash, nil, chainDb),
+		shutdownChan:   make(chan bool),
+		networkId:      config.NetworkId,
+		bloomRequests:  make(chan chan *bloombits.Retrieval),
+		bloomIndexer:   eth.NewBloomIndexer(chainDb, light.BloomTrieFrequency, light.HelperTrieConfirmations),
 	}
 
 	leth.relay = NewLesTxRelay(peers, leth.reqDist)
 	leth.serverPool = newServerPool(chainDb, quitSync, &leth.wg)
 	leth.retriever = newRetrieveManager(peers, leth.reqDist, leth.serverPool)
-	leth.odr = NewLesOdr(chainDb, leth.chtIndexer, leth.bloomTrieIndexer, leth.bloomIndexer, leth.retriever)
+	leth.odr = NewLesOdr(chainDb, leth.retriever)
+	leth.chtIndexer = light.NewChtIndexer(chainDb, true, leth.odr)
+	leth.bloomTrieIndexer = light.NewBloomTrieIndexer(chainDb, true, leth.odr)
+	leth.odr.SetIndexers(leth.chtIndexer, leth.bloomTrieIndexer, leth.bloomIndexer)
+	// Note: NewLightChain adds the trusted checkpoint so it needs an ODR with
+	// indexers already set but not started yet
 	if leth.blockchain, err = light.NewLightChain(leth.odr, leth.chainConfig, leth.engine); err != nil {
 		return nil, err
 	}
+	// Note: AddChildIndexer starts the update process for the child
+	leth.bloomIndexer.AddChildIndexer(leth.bloomTrieIndexer)
+	leth.chtIndexer.Start(leth.blockchain)
 	leth.bloomIndexer.Start(leth.blockchain)
 	// Rewind the chain in case of an incompatible config upgrade.
 	if compat, ok := genesisErr.(*params.ConfigCompatError); ok {
@@ -242,9 +248,6 @@ func (s *LightEthereum) Stop() error {
 	if s.chtIndexer != nil {
 		s.chtIndexer.Close()
 	}
-	if s.bloomTrieIndexer != nil {
-		s.bloomTrieIndexer.Close()
-	}
 	s.blockchain.Stop()
 	s.protocolManager.Stop()
 	s.txPool.Stop()