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.

2 files changed, 12 insertions, 13 deletions

diff --git a/eth/backend.go b/eth/backend.go
index 865534b19..6549cb8a3 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -130,7 +130,7 @@ func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
 		gasPrice:       config.GasPrice,
 		etherbase:      config.Etherbase,
 		bloomRequests:  make(chan chan *bloombits.Retrieval),
-		bloomIndexer:   NewBloomIndexer(chainDb, params.BloomBitsBlocks),
+		bloomIndexer:   NewBloomIndexer(chainDb, params.BloomBitsBlocks, bloomConfirms),
 	}
 
 	log.Info("Initialising Ethereum protocol", "versions", ProtocolVersions, "network", config.NetworkId)
diff --git a/eth/bloombits.go b/eth/bloombits.go
index 954239d14..eb18565e2 100644
--- a/eth/bloombits.go
+++ b/eth/bloombits.go
@@ -17,6 +17,7 @@
 package eth
 
 import (
+	"context"
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
@@ -92,30 +93,28 @@ const (
 // BloomIndexer implements a core.ChainIndexer, building up a rotated bloom bits index
 // for the Ethereum header bloom filters, permitting blazing fast filtering.
 type BloomIndexer struct {
-	size uint64 // section size to generate bloombits for
-
-	db  ethdb.Database       // database instance to write index data and metadata into
-	gen *bloombits.Generator // generator to rotate the bloom bits crating the bloom index
-
-	section uint64      // Section is the section number being processed currently
-	head    common.Hash // Head is the hash of the last header processed
+	size    uint64               // section size to generate bloombits for
+	db      ethdb.Database       // database instance to write index data and metadata into
+	gen     *bloombits.Generator // generator to rotate the bloom bits crating the bloom index
+	section uint64               // Section is the section number being processed currently
+	head    common.Hash          // Head is the hash of the last header processed
 }
 
 // NewBloomIndexer returns a chain indexer that generates bloom bits data for the
 // canonical chain for fast logs filtering.
-func NewBloomIndexer(db ethdb.Database, size uint64) *core.ChainIndexer {
+func NewBloomIndexer(db ethdb.Database, size, confReq uint64) *core.ChainIndexer {
 	backend := &BloomIndexer{
 		db:   db,
 		size: size,
 	}
 	table := ethdb.NewTable(db, string(rawdb.BloomBitsIndexPrefix))
 
-	return core.NewChainIndexer(db, table, backend, size, bloomConfirms, bloomThrottling, "bloombits")
+	return core.NewChainIndexer(db, table, backend, size, confReq, bloomThrottling, "bloombits")
 }
 
 // Reset implements core.ChainIndexerBackend, starting a new bloombits index
 // section.
-func (b *BloomIndexer) Reset(section uint64, lastSectionHead common.Hash) error {
+func (b *BloomIndexer) Reset(ctx context.Context, section uint64, lastSectionHead common.Hash) error {
 	gen, err := bloombits.NewGenerator(uint(b.size))
 	b.gen, b.section, b.head = gen, section, common.Hash{}
 	return err
@@ -123,16 +122,16 @@ func (b *BloomIndexer) Reset(section uint64, lastSectionHead common.Hash) error
 
 // Process implements core.ChainIndexerBackend, adding a new header's bloom into
 // the index.
-func (b *BloomIndexer) Process(header *types.Header) {
+func (b *BloomIndexer) Process(ctx context.Context, header *types.Header) error {
 	b.gen.AddBloom(uint(header.Number.Uint64()-b.section*b.size), header.Bloom)
 	b.head = header.Hash()
+	return nil
 }
 
 // Commit implements core.ChainIndexerBackend, finalizing the bloom section and
 // writing it out into the database.
 func (b *BloomIndexer) Commit() error {
 	batch := b.db.NewBatch()
-
 	for i := 0; i < types.BloomBitLength; i++ {
 		bits, err := b.gen.Bitset(uint(i))
 		if err != nil {