Further LES cleanup

cmd/utils/flags.go

@@ -20,6 +20,7 @@ package utils
 import (
 	"crypto/ecdsa"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"io/ioutil"
 	"math/big"
@@ -1470,26 +1471,51 @@ func SetDashboardConfig(ctx *cli.Context, cfg *dashboard.Config) {
 	cfg.Refresh = ctx.GlobalDuration(DashboardRefreshFlag.Name)
 }
 
-// RegisterEthService adds an Ethereum client to the stack.
+// RegisterLesClientService adds a Light Client service to the stack if the config permits
-func RegisterEthService(stack *node.Node, cfg *eth.Config) {
+func RegisterLesClientService(stack *node.Node, cfg *eth.Config) {
-	var err error
+
+	//if the light client is requested
 	if cfg.SyncMode == downloader.LightSync {
-		err = stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
+		//register a light client
+		if err := stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
 			return les.New(ctx, cfg)
-		})
+		}); err != nil {
-	} else {
+			Fatalf("Failed to register the Light Client service: %v", err)
-		err = stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
-			fullNode, err := eth.New(ctx, cfg)
-			if fullNode != nil && cfg.LightServ > 0 {
-				ls, _ := les.NewLesServer(fullNode, cfg)
-				fullNode.AddLesServer(ls)
 		}
-			return fullNode, err
-		})
 	}
-	if err != nil {
+}
+
+// RegisterLesServerService adds a Light Server service to the stack if the config permits
+func RegisterLesServerService(stack *node.Node, cfg *eth.Config) {
+
+	//if the light client is not requested and the light server is requested
+	if cfg.SyncMode != downloader.LightSync && cfg.LightServ > 0 {
+		//register a light server service
+		if err := stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
+			//check if the main Eth protocol service is running
+			var ethService *eth.Ethereum
+			if ctx.Service(&ethService) != nil {
+				return nil, errors.New("Failed to start the Les Server service because Ethereum service is not running")
+			}
+			return les.NewLesServer(ethService, cfg)
+		}); err != nil {
+			Fatalf("Failed to register the Light Server service: %v", err)
+		}
+	}
+}
+
+// RegisterEthService adds an Ethereum client to the stack if the config permits
+func RegisterEthService(stack *node.Node, cfg *eth.Config) {
+
+	//if the light client is not requested
+	if cfg.SyncMode != downloader.LightSync {
+		//register a service for the Eth protocol
+		if err := stack.Register(func(ctx *node.ServiceContext) (node.Service, error) {
+			return eth.New(ctx, cfg)
+		}); err != nil {
 			Fatalf("Failed to register the Ethereum service: %v", err)
 		}
+	}
 }
 
 // RegisterDashboardService adds a dashboard to the stack.

eth/backend.go

@@ -51,14 +51,6 @@ import (
 	"github.com/ethereum/go-ethereum/rpc"
 )
 
-type LesServer interface {
-	Start(srvr *p2p.Server)
-	Stop()
-	APIs() []rpc.API
-	Protocols() []p2p.Protocol
-	SetBloomBitsIndexer(bbIndexer *core.ChainIndexer)
-}
-
 // Ethereum implements the Ethereum full node service.
 type Ethereum struct {
 	config *Config
@@ -70,7 +62,6 @@ type Ethereum struct {
 	txPool          *core.TxPool
 	blockchain      *core.BlockChain
 	protocolManager *ProtocolManager
-	lesServer       LesServer
 
 	// DB interfaces
 	chainDb ethdb.Database // Block chain database
@@ -94,11 +85,6 @@ type Ethereum struct {
 	lock sync.RWMutex // Protects the variadic fields (e.g. gas price and etherbase)
 }
 
-func (s *Ethereum) AddLesServer(ls LesServer) {
-	s.lesServer = ls
-	ls.SetBloomBitsIndexer(s.bloomIndexer)
-}
-
 // New creates a new Ethereum object (including the
 // initialisation of the common Ethereum object)
 func New(ctx *node.ServiceContext, config *Config) (*Ethereum, error) {
@@ -256,15 +242,13 @@ func CreateConsensusEngine(ctx *node.ServiceContext, chainConfig *params.ChainCo
 	}
 }
 
+
+
 // APIs return the collection of RPC services the ethereum package offers.
 // NOTE, some of these services probably need to be moved to somewhere else.
 func (s *Ethereum) APIs() []rpc.API {
 	apis := ethapi.GetAPIs(s.APIBackend)
 
-	// Append any APIs exposed explicitly by the les server
-	if s.lesServer != nil {
-		apis = append(apis, s.lesServer.APIs()...)
-	}
 	// Append any APIs exposed explicitly by the consensus engine
 	apis = append(apis, s.engine.APIs(s.BlockChain())...)
 
@@ -316,6 +300,11 @@ func (s *Ethereum) APIs() []rpc.API {
 		},
 	}...)
 }
+// GetBloomIndexer returns the bloombits indexer, primarily
+// so that the Les Server service can re-use it
+func (s *Ethereum) GetBloomIndexer() *core.ChainIndexer {
+	return s.bloomIndexer
+}
 
 func (s *Ethereum) ResetWithGenesisBlock(gb *types.Block) {
 	s.blockchain.ResetWithGenesisBlock(gb)
@@ -485,10 +474,7 @@ func (s *Ethereum) Synced() bool                       { return atomic.LoadUint3
 // Protocols implements node.Service, returning all the currently configured
 // network protocols to start.
 func (s *Ethereum) Protocols() []p2p.Protocol {
-	if s.lesServer == nil {
 		return s.protocolManager.SubProtocols
-	}
-	return append(s.protocolManager.SubProtocols, s.lesServer.Protocols()...)
 }
 
 // Start implements node.Service, starting all internal goroutines needed by the
@@ -508,11 +494,10 @@ func (s *Ethereum) Start(srvr *p2p.Server) error {
 		}
 		maxPeers -= s.config.LightPeers
 	}
+
 	// Start the networking layer and the light server if requested
 	s.protocolManager.Start(maxPeers)
-	if s.lesServer != nil {
+
-		s.lesServer.Start(srvr)
-	}
 	return nil
 }
 
@@ -523,13 +508,9 @@ func (s *Ethereum) Stop() error {
 	s.blockchain.Stop()
 	s.engine.Close()
 	s.protocolManager.Stop()
-	if s.lesServer != nil {
-		s.lesServer.Stop()
-	}
 	s.txPool.Stop()
 	s.miner.Stop()
 	s.eventMux.Stop()
-
 	s.chainDb.Close()
 	close(s.shutdownChan)
 	return nil

go-ethereum.code-workspace

@@ -0,0 +1,8 @@
+{
+	"folders": [
+		{
+			"path": "."
+		}
+	],
+	"settings": {}
+}

les/api.go

@@ -29,8 +29,11 @@ import (
 )
 
 var (
+	// ErrMinCap capacity too small
 	ErrMinCap = errors.New("capacity too small")
+	// ErrTotalCap total capacity exceeded
 	ErrTotalCap = errors.New("total capacity exceeded")
+	// ErrUnknownBenchmarkType unknown benchmark type
 	ErrUnknownBenchmarkType = errors.New("unknown benchmark type")
 
 	dropCapacityDelay = time.Second // delay applied to decreasing capacity changes

les/api_backend.go

@@ -39,37 +39,44 @@ import (
 	"github.com/ethereum/go-ethereum/rpc"
 )
 
-type LesApiBackend struct {
+// ClientBackend is a backend implementation for the light Client only
+type ClientBackend struct {
 	extRPCEnabled bool
 	eth           *LightEthereum
 	gpo           *gasprice.Oracle
 }
 
-func (b *LesApiBackend) ChainConfig() *params.ChainConfig {
+// ChainConfig returns the LightEthereum service config
+func (b *ClientBackend) ChainConfig() *params.ChainConfig {
 	return b.eth.chainConfig
 }
 
-func (b *LesApiBackend) CurrentBlock() *types.Block {
+// CurrentBlock returns the LightEthereum service chain current header block
+func (b *ClientBackend) CurrentBlock() *types.Block {
 	return types.NewBlockWithHeader(b.eth.BlockChain().CurrentHeader())
 }
 
-func (b *LesApiBackend) SetHead(number uint64) {
+// SetHead cancels the downloader and sets the head to a certain number
+func (b *ClientBackend) SetHead(number uint64) {
 	b.eth.protocolManager.downloader.Cancel()
 	b.eth.blockchain.SetHead(number)
 }
 
-func (b *LesApiBackend) HeaderByNumber(ctx context.Context, blockNr rpc.BlockNumber) (*types.Header, error) {
+// HeaderByNumber returns either the chain's current header or an on-demand-requested header, given a block number
+func (b *ClientBackend) HeaderByNumber(ctx context.Context, blockNr rpc.BlockNumber) (*types.Header, error) {
 	if blockNr == rpc.LatestBlockNumber || blockNr == rpc.PendingBlockNumber {
 		return b.eth.blockchain.CurrentHeader(), nil
 	}
 	return b.eth.blockchain.GetHeaderByNumberOdr(ctx, uint64(blockNr))
 }
 
-func (b *LesApiBackend) HeaderByHash(ctx context.Context, hash common.Hash) (*types.Header, error) {
+// HeaderByHash returns a block header for the given block hash
+func (b *ClientBackend) HeaderByHash(ctx context.Context, hash common.Hash) (*types.Header, error) {
 	return b.eth.blockchain.GetHeaderByHash(hash), nil
 }
 
-func (b *LesApiBackend) BlockByNumber(ctx context.Context, blockNr rpc.BlockNumber) (*types.Block, error) {
+// BlockByNumber identifies a header by number and then returns the block with the corresponding block hash
+func (b *ClientBackend) BlockByNumber(ctx context.Context, blockNr rpc.BlockNumber) (*types.Block, error) {
 	header, err := b.HeaderByNumber(ctx, blockNr)
 	if header == nil || err != nil {
 		return nil, err
@@ -77,7 +84,8 @@ func (b *LesApiBackend) BlockByNumber(ctx context.Context, blockNr rpc.BlockNumb
 	return b.GetBlock(ctx, header.Hash())
 }
 
-func (b *LesApiBackend) StateAndHeaderByNumber(ctx context.Context, blockNr rpc.BlockNumber) (*state.StateDB, *types.Header, error) {
+// StateAndHeaderByNumber identifies a block header by the supplied number, then returns that header's associated state and the header itself
+func (b *ClientBackend) StateAndHeaderByNumber(ctx context.Context, blockNr rpc.BlockNumber) (*state.StateDB, *types.Header, error) {
 	header, err := b.HeaderByNumber(ctx, blockNr)
 	if err != nil {
 		return nil, nil, err
@@ -88,123 +96,157 @@ func (b *LesApiBackend) StateAndHeaderByNumber(ctx context.Context, blockNr rpc.
 	return light.NewState(ctx, header, b.eth.odr), header, nil
 }
 
-func (b *LesApiBackend) GetBlock(ctx context.Context, blockHash common.Hash) (*types.Block, error) {
+// GetBlock returns a block identified by block hash
+func (b *ClientBackend) GetBlock(ctx context.Context, blockHash common.Hash) (*types.Block, error) {
 	return b.eth.blockchain.GetBlockByHash(ctx, blockHash)
 }
 
-func (b *LesApiBackend) GetReceipts(ctx context.Context, hash common.Hash) (types.Receipts, error) {
+// GetReceipts returns a set of receipts for a block, identified by the supplied hash
+func (b *ClientBackend) GetReceipts(ctx context.Context, hash common.Hash) (types.Receipts, error) {
 	if number := rawdb.ReadHeaderNumber(b.eth.chainDb, hash); number != nil {
 		return light.GetBlockReceipts(ctx, b.eth.odr, hash, *number)
 	}
 	return nil, nil
 }
 
-func (b *LesApiBackend) GetLogs(ctx context.Context, hash common.Hash) ([][]*types.Log, error) {
+// GetLogs identifies the block header number given the supplied hash and then returns the block logs
+func (b *ClientBackend) GetLogs(ctx context.Context, hash common.Hash) ([][]*types.Log, error) {
 	if number := rawdb.ReadHeaderNumber(b.eth.chainDb, hash); number != nil {
 		return light.GetBlockLogs(ctx, b.eth.odr, hash, *number)
 	}
 	return nil, nil
 }
 
-func (b *LesApiBackend) GetTd(hash common.Hash) *big.Int {
+// GetTd retrieves a block's total difficulty in the canonical chain by hash
+func (b *ClientBackend) GetTd(hash common.Hash) *big.Int {
 	return b.eth.blockchain.GetTdByHash(hash)
 }
 
-func (b *LesApiBackend) GetEVM(ctx context.Context, msg core.Message, state *state.StateDB, header *types.Header) (*vm.EVM, func() error, error) {
+// GetEVM creates an EVM initialised with an account and balance from the supplied message
+func (b *ClientBackend) GetEVM(ctx context.Context, msg core.Message, state *state.StateDB, header *types.Header) (*vm.EVM, func() error, error) {
 	state.SetBalance(msg.From(), math.MaxBig256)
 	context := core.NewEVMContext(msg, header, b.eth.blockchain, nil)
 	return vm.NewEVM(context, state, b.eth.chainConfig, vm.Config{}), state.Error, nil
 }
 
-func (b *LesApiBackend) SendTx(ctx context.Context, signedTx *types.Transaction) error {
+// SendTx add the transaction to the local transaction pool
+func (b *ClientBackend) SendTx(ctx context.Context, signedTx *types.Transaction) error {
 	return b.eth.txPool.Add(ctx, signedTx)
 }
 
-func (b *LesApiBackend) RemoveTx(txHash common.Hash) {
+// RemoveTx removes a transaction from the local transaction pool
+func (b *ClientBackend) RemoveTx(txHash common.Hash) {
 	b.eth.txPool.RemoveTx(txHash)
 }
 
-func (b *LesApiBackend) GetPoolTransactions() (types.Transactions, error) {
+// GetPoolTransactions returns all currently processable transactions.
+func (b *ClientBackend) GetPoolTransactions() (types.Transactions, error) {
 	return b.eth.txPool.GetTransactions()
 }
 
-func (b *LesApiBackend) GetPoolTransaction(txHash common.Hash) *types.Transaction {
+// GetPoolTransaction returns a transaction if it is contained in the pool and nil otherwise.
+func (b *ClientBackend) GetPoolTransaction(txHash common.Hash) *types.Transaction {
 	return b.eth.txPool.GetTransaction(txHash)
 }
 
-func (b *LesApiBackend) GetTransaction(ctx context.Context, txHash common.Hash) (*types.Transaction, common.Hash, uint64, uint64, error) {
+// GetTransaction retrieves a canonical transaction by hash and also returns its position in the chain
+func (b *ClientBackend) GetTransaction(ctx context.Context, txHash common.Hash) (*types.Transaction, common.Hash, uint64, uint64, error) {
 	return light.GetTransaction(ctx, b.eth.odr, txHash)
 }
 
-func (b *LesApiBackend) GetPoolNonce(ctx context.Context, addr common.Address) (uint64, error) {
+// GetPoolNonce returns the "pending" nonce of a given address. It always queries
+// the nonce belonging to the latest header too in order to detect if another
+// client using the same key sent a transaction.
+func (b *ClientBackend) GetPoolNonce(ctx context.Context, addr common.Address) (uint64, error) {
 	return b.eth.txPool.GetNonce(ctx, addr)
 }
 
-func (b *LesApiBackend) Stats() (pending int, queued int) {
+// Stats returns the number of currently pending (locally created) transactions
+func (b *ClientBackend) Stats() (pending int, queued int) {
 	return b.eth.txPool.Stats(), 0
 }
 
-func (b *LesApiBackend) TxPoolContent() (map[common.Address]types.Transactions, map[common.Address]types.Transactions) {
+// TxPoolContent retrieves the data content of the transaction pool, returning all the
+// pending as well as queued transactions, grouped by account and nonce.
+func (b *ClientBackend) TxPoolContent() (map[common.Address]types.Transactions, map[common.Address]types.Transactions) {
 	return b.eth.txPool.Content()
 }
 
-func (b *LesApiBackend) SubscribeNewTxsEvent(ch chan<- core.NewTxsEvent) event.Subscription {
+// SubscribeNewTxsEvent registers a subscription of core.NewTxsEvent and
+// starts sending event to the given channel.
+func (b *ClientBackend) SubscribeNewTxsEvent(ch chan<- core.NewTxsEvent) event.Subscription {
 	return b.eth.txPool.SubscribeNewTxsEvent(ch)
 }
 
-func (b *LesApiBackend) SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription {
+// SubscribeChainEvent registers a subscription of ChainEvent.
+func (b *ClientBackend) SubscribeChainEvent(ch chan<- core.ChainEvent) event.Subscription {
 	return b.eth.blockchain.SubscribeChainEvent(ch)
 }
 
-func (b *LesApiBackend) SubscribeChainHeadEvent(ch chan<- core.ChainHeadEvent) event.Subscription {
+// SubscribeChainHeadEvent registers a subscription of ChainHeadEvent.
+func (b *ClientBackend) SubscribeChainHeadEvent(ch chan<- core.ChainHeadEvent) event.Subscription {
 	return b.eth.blockchain.SubscribeChainHeadEvent(ch)
 }
 
-func (b *LesApiBackend) SubscribeChainSideEvent(ch chan<- core.ChainSideEvent) event.Subscription {
+// SubscribeChainSideEvent registers a subscription of ChainSideEvent.
+func (b *ClientBackend) SubscribeChainSideEvent(ch chan<- core.ChainSideEvent) event.Subscription {
 	return b.eth.blockchain.SubscribeChainSideEvent(ch)
 }
 
-func (b *LesApiBackend) SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription {
+// SubscribeLogsEvent implements the interface of filters.Backend
+// LightChain does not send logs events, so return an empty subscription.
+func (b *ClientBackend) SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription {
 	return b.eth.blockchain.SubscribeLogsEvent(ch)
 }
 
-func (b *LesApiBackend) SubscribeRemovedLogsEvent(ch chan<- core.RemovedLogsEvent) event.Subscription {
+// SubscribeRemovedLogsEvent implements the interface of filters.Backend
+// LightChain does not send core.RemovedLogsEvent, so return an empty subscription.
+func (b *ClientBackend) SubscribeRemovedLogsEvent(ch chan<- core.RemovedLogsEvent) event.Subscription {
 	return b.eth.blockchain.SubscribeRemovedLogsEvent(ch)
 }
 
-func (b *LesApiBackend) Downloader() *downloader.Downloader {
+// Downloader returns the LightEthereum downloader
+func (b *ClientBackend) Downloader() *downloader.Downloader {
 	return b.eth.Downloader()
 }
 
-func (b *LesApiBackend) ProtocolVersion() int {
+// ProtocolVersion return the Les version number offset by 10000
+func (b *ClientBackend) ProtocolVersion() int {
 	return b.eth.LesVersion() + 10000
 }
 
-func (b *LesApiBackend) SuggestPrice(ctx context.Context) (*big.Int, error) {
+// SuggestPrice returns the gas price oracle price suggestion
+func (b *ClientBackend) SuggestPrice(ctx context.Context) (*big.Int, error) {
 	return b.gpo.SuggestPrice(ctx)
 }
 
-func (b *LesApiBackend) ChainDb() ethdb.Database {
+// ChainDb returns the ClientBackend db representation
+func (b *ClientBackend) ChainDb() ethdb.Database {
 	return b.eth.chainDb
 }
 
-func (b *LesApiBackend) EventMux() *event.TypeMux {
+// EventMux ...
+func (b *ClientBackend) EventMux() *event.TypeMux {
 	return b.eth.eventMux
 }
 
-func (b *LesApiBackend) AccountManager() *accounts.Manager {
+// AccountManager returns an overarching account manager needed for signing transactions
+func (b *ClientBackend) AccountManager() *accounts.Manager {
 	return b.eth.accountManager
 }
 
-func (b *LesApiBackend) ExtRPCEnabled() bool {
+// ExtRPCEnabled indicates if the external RPC API is enabled
+func (b *ClientBackend) ExtRPCEnabled() bool {
 	return b.extRPCEnabled
 }
 
-func (b *LesApiBackend) RPCGasCap() *big.Int {
+// RPCGasCap - return the  global gas cap for eth_call over rpc (DoS protection)
+func (b *ClientBackend) RPCGasCap() *big.Int {
 	return b.eth.config.RPCGasCap
 }
 
-func (b *LesApiBackend) BloomStatus() (uint64, uint64) {
+// BloomStatus ..
+func (b *ClientBackend) BloomStatus() (uint64, uint64) {
 	if b.eth.bloomIndexer == nil {
 		return 0, 0
 	}
@@ -212,7 +254,8 @@ func (b *LesApiBackend) BloomStatus() (uint64, uint64) {
 	return params.BloomBitsBlocksClient, sections
 }
 
-func (b *LesApiBackend) ServiceFilter(ctx context.Context, session *bloombits.MatcherSession) {
+// ServiceFilter ...
+func (b *ClientBackend) ServiceFilter(ctx context.Context, session *bloombits.MatcherSession) {
 	for i := 0; i < bloomFilterThreads; i++ {
 		go session.Multiplex(bloomRetrievalBatch, bloomRetrievalWait, b.eth.bloomRequests)
 	}

les/api_test.go

@@ -90,15 +90,15 @@ func testCapacityAPI(t *testing.T, clientCount int) {
 		}
 		server := servers[0]
 
-		clientRpcClients := make([]*rpc.Client, len(clients))
+		clientRPCClients := make([]*rpc.Client, len(clients))
 
-		serverRpcClient, err := server.Client()
+		serverRPCClient, err := server.Client()
 		if err != nil {
 			t.Fatalf("Failed to obtain rpc client: %v", err)
 		}
-		headNum, headHash := getHead(ctx, t, serverRpcClient)
+		headNum, headHash := getHead(ctx, t, serverRPCClient)
-		totalCap := getTotalCap(ctx, t, serverRpcClient)
+		totalCap := getTotalCap(ctx, t, serverRPCClient)
-		minCap := getMinCap(ctx, t, serverRpcClient)
+		minCap := getMinCap(ctx, t, serverRPCClient)
 		testCap := totalCap * 3 / 4
 		fmt.Printf("Server testCap: %d  minCap: %d  head number: %d  head hash: %064x\n", testCap, minCap, headNum, headHash)
 		reqMinCap := uint64(float64(testCap) * minRelCap / (minRelCap + float64(len(clients)-1)))
@@ -107,18 +107,18 @@ func testCapacityAPI(t *testing.T, clientCount int) {
 		}
 
 		freeIdx := rand.Intn(len(clients))
-		freeCap := getFreeCap(ctx, t, serverRpcClient)
+		freeCap := getFreeCap(ctx, t, serverRPCClient)
 
 		for i, client := range clients {
 			var err error
-			clientRpcClients[i], err = client.Client()
+			clientRPCClients[i], err = client.Client()
 			if err != nil {
 				t.Fatalf("Failed to obtain rpc client: %v", err)
 			}
 
 			fmt.Println("connecting client", i)
 			if i != freeIdx {
-				setCapacity(ctx, t, serverRpcClient, client.ID(), testCap/uint64(len(clients)))
+				setCapacity(ctx, t, serverRPCClient, client.ID(), testCap/uint64(len(clients)))
 			}
 			net.Connect(client.ID(), server.ID())
 
@@ -128,7 +128,7 @@ func testCapacityAPI(t *testing.T, clientCount int) {
 					t.Fatalf("Timeout")
 				default:
 				}
-				num, hash := getHead(ctx, t, clientRpcClients[i])
+				num, hash := getHead(ctx, t, clientRPCClients[i])
 				if num == headNum && hash == headHash {
 					fmt.Println("client", i, "synced")
 					break
@@ -140,9 +140,9 @@ func testCapacityAPI(t *testing.T, clientCount int) {
 		var wg sync.WaitGroup
 		stop := make(chan struct{})
 
-		reqCount := make([]uint64, len(clientRpcClients))
+		reqCount := make([]uint64, len(clientRPCClients))
 
-		for i, c := range clientRpcClients {
+		for i, c := range clientRPCClients {
 			wg.Add(1)
 			i, c := i, c
 			go func() {
@@ -194,7 +194,7 @@ func testCapacityAPI(t *testing.T, clientCount int) {
 
 		weights := make([]float64, len(clients))
 		for c := 0; c < 5; c++ {
-			setCapacity(ctx, t, serverRpcClient, clients[freeIdx].ID(), freeCap)
+			setCapacity(ctx, t, serverRPCClient, clients[freeIdx].ID(), freeCap)
 			freeIdx = rand.Intn(len(clients))
 			var sum float64
 			for i := range clients {
@@ -208,15 +208,15 @@ func testCapacityAPI(t *testing.T, clientCount int) {
 			for i, client := range clients {
 				weights[i] *= float64(testCap-freeCap-100) / sum
 				capacity := uint64(weights[i])
-				if i != freeIdx && capacity < getCapacity(ctx, t, serverRpcClient, client.ID()) {
+				if i != freeIdx && capacity < getCapacity(ctx, t, serverRPCClient, client.ID()) {
-					setCapacity(ctx, t, serverRpcClient, client.ID(), capacity)
+					setCapacity(ctx, t, serverRPCClient, client.ID(), capacity)
 				}
 			}
-			setCapacity(ctx, t, serverRpcClient, clients[freeIdx].ID(), 0)
+			setCapacity(ctx, t, serverRPCClient, clients[freeIdx].ID(), 0)
 			for i, client := range clients {
 				capacity := uint64(weights[i])
-				if i != freeIdx && capacity > getCapacity(ctx, t, serverRpcClient, client.ID()) {
+				if i != freeIdx && capacity > getCapacity(ctx, t, serverRPCClient, client.ID()) {
-					setCapacity(ctx, t, serverRpcClient, client.ID(), capacity)
+					setCapacity(ctx, t, serverRPCClient, client.ID(), capacity)
 				}
 			}
 			weights[freeIdx] = float64(freeCap)
@@ -239,7 +239,7 @@ func testCapacityAPI(t *testing.T, clientCount int) {
 				default:
 				}
 
-				totalCap = getTotalCap(ctx, t, serverRpcClient)
+				totalCap = getTotalCap(ctx, t, serverRPCClient)
 				if totalCap < testCap {
 					fmt.Println("Total capacity underrun")
 					close(stop)
@@ -520,6 +520,6 @@ func newLesServerService(ctx *adapters.ServiceContext) (node.Service, error) {
 	if err != nil {
 		return nil, err
 	}
-	ethereum.AddLesServer(server)
+
-	return ethereum, nil
+	return server, nil
 }

les/backend.go

@@ -46,6 +46,7 @@ import (
 	rpc "github.com/ethereum/go-ethereum/rpc"
 )
 
+// LightEthereum is a light client service
 type LightEthereum struct {
 	lesCommons
 
@@ -66,18 +67,19 @@ type LightEthereum struct {
 	bloomRequests chan chan *bloombits.Retrieval // Channel receiving bloom data retrieval requests
 	bloomIndexer  *core.ChainIndexer
 
-	ApiBackend *LesApiBackend
+	APIBackend *ClientBackend
 
 	eventMux       *event.TypeMux
 	engine         consensus.Engine
 	accountManager *accounts.Manager
 
-	networkId     uint64
+	networkID     uint64
 	netRPCService *ethapi.PublicNetAPI
 
 	wg sync.WaitGroup
 }
 
+// New constructs a LightEthereum client
 func New(ctx *node.ServiceContext, config *eth.Config) (*LightEthereum, error) {
 	chainDb, err := ctx.OpenDatabase("lightchaindata", config.DatabaseCache, config.DatabaseHandles, "eth/db/chaindata/")
 	if err != nil {
@@ -105,7 +107,7 @@ func New(ctx *node.ServiceContext, config *eth.Config) (*LightEthereum, error) {
 		accountManager: ctx.AccountManager,
 		engine:         eth.CreateConsensusEngine(ctx, chainConfig, &config.Ethash, nil, false, chainDb),
 		shutdownChan:   make(chan bool),
-		networkId:      config.NetworkId,
+		networkID:      config.NetworkId,
 		bloomRequests:  make(chan chan *bloombits.Retrieval),
 		bloomIndexer:   eth.NewBloomIndexer(chainDb, params.BloomBitsBlocksClient, params.HelperTrieConfirmations),
 	}
@@ -167,13 +169,13 @@ func New(ctx *node.ServiceContext, config *eth.Config) (*LightEthereum, error) {
 		log.Warn("Ultra light client is enabled", "trustedNodes", len(leth.protocolManager.ulc.trustedKeys), "minTrustedFraction", leth.protocolManager.ulc.minTrustedFraction)
 		leth.blockchain.DisableCheckFreq()
 	}
-	leth.ApiBackend = &LesApiBackend{ctx.ExtRPCEnabled(), leth, nil}
+	leth.APIBackend = &ClientBackend{ctx.ExtRPCEnabled(), leth, nil}
 
 	gpoParams := config.GPO
 	if gpoParams.Default == nil {
 		gpoParams.Default = config.Miner.GasPrice
 	}
-	leth.ApiBackend.gpo = gasprice.NewOracle(leth.ApiBackend, gpoParams)
+	leth.APIBackend.gpo = gasprice.NewOracle(leth.APIBackend, gpoParams)
 	return leth, nil
 }
 
@@ -188,6 +190,7 @@ func lesTopic(genesisHash common.Hash, protocolVersion uint) discv5.Topic {
 	return discv5.Topic(name + "@" + common.Bytes2Hex(genesisHash.Bytes()[0:8]))
 }
 
+// LightDummyAPI is a fake api that serves default values in the role of a light client
 type LightDummyAPI struct{}
 
 // Etherbase is the address that mining rewards will be send to
@@ -213,7 +216,7 @@ func (s *LightDummyAPI) Mining() bool {
 // APIs returns the collection of RPC services the ethereum package offers.
 // NOTE, some of these services probably need to be moved to somewhere else.
 func (s *LightEthereum) APIs() []rpc.API {
-	return append(ethapi.GetAPIs(s.ApiBackend), []rpc.API{
+	return append(ethapi.GetAPIs(s.APIBackend), []rpc.API{
 		{
 			Namespace: "eth",
 			Version:   "1.0",
@@ -227,7 +230,7 @@ func (s *LightEthereum) APIs() []rpc.API {
 		}, {
 			Namespace: "eth",
 			Version:   "1.0",
-			Service:   filters.NewPublicFilterAPI(s.ApiBackend, true),
+			Service:   filters.NewPublicFilterAPI(s.APIBackend, true),
 			Public:    true,
 		}, {
 			Namespace: "net",
@@ -238,15 +241,28 @@ func (s *LightEthereum) APIs() []rpc.API {
 	}...)
 }
 
+// ResetWithGenesisBlock purges the entire blockchain, restoring it to the
+// specified genesis state.
 func (s *LightEthereum) ResetWithGenesisBlock(gb *types.Block) {
 	s.blockchain.ResetWithGenesisBlock(gb)
 }
 
+// BlockChain returns the light client's blockchain
 func (s *LightEthereum) BlockChain() *light.LightChain { return s.blockchain }
+
+// TxPool the pool of locally created transactions
 func (s *LightEthereum) TxPool() *light.TxPool { return s.txPool }
+
+// Engine is the employed consensus engine
 func (s *LightEthereum) Engine() consensus.Engine { return s.engine }
+
+// LesVersion is the current version of Les used by this light client
 func (s *LightEthereum) LesVersion() int { return int(ClientProtocolVersions[0]) }
+
+// Downloader is the employed downloader
 func (s *LightEthereum) Downloader() *downloader.Downloader { return s.protocolManager.downloader }
+
+// EventMux is an event subscription notifier
 func (s *LightEthereum) EventMux() *event.TypeMux { return s.eventMux }
 
 // Protocols implements node.Service, returning all the currently configured
@@ -260,7 +276,7 @@ func (s *LightEthereum) Protocols() []p2p.Protocol {
 func (s *LightEthereum) Start(srvr *p2p.Server) error {
 	log.Warn("Light client mode is an experimental feature")
 	s.startBloomHandlers(params.BloomBitsBlocksClient)
-	s.netRPCService = ethapi.NewPublicNetAPI(srvr, s.networkId)
+	s.netRPCService = ethapi.NewPublicNetAPI(srvr, s.networkID)
 	// clients are searching for the first advertised protocol in the list
 	protocolVersion := AdvertiseProtocolVersions[0]
 	s.serverPool.start(srvr, lesTopic(s.blockchain.Genesis().Hash(), protocolVersion))

les/benchmark.go

@@ -74,9 +74,9 @@ func (b *benchmarkBlockHeaders) init(pm *ProtocolManager, count int) error {
 func (b *benchmarkBlockHeaders) request(peer *peer, index int) error {
 	if b.byHash {
 		return peer.RequestHeadersByHash(0, 0, b.hashes[index], b.amount, b.skip, b.reverse)
-	} else {
-		return peer.RequestHeadersByNumber(0, 0, uint64(b.offset+rand.Int63n(b.randMax)), b.amount, b.skip, b.reverse)
 	}
+	return peer.RequestHeadersByNumber(0, 0, uint64(b.offset+rand.Int63n(b.randMax)), b.amount, b.skip, b.reverse)
+
 }
 
 // benchmarkBodiesOrReceipts implements requestBenchmark
@@ -97,9 +97,9 @@ func (b *benchmarkBodiesOrReceipts) init(pm *ProtocolManager, count int) error {
 func (b *benchmarkBodiesOrReceipts) request(peer *peer, index int) error {
 	if b.receipts {
 		return peer.RequestReceipts(0, 0, []common.Hash{b.hashes[index]})
-	} else {
-		return peer.RequestBodies(0, 0, []common.Hash{b.hashes[index]})
 	}
+	return peer.RequestBodies(0, 0, []common.Hash{b.hashes[index]})
+
 }
 
 // benchmarkProofsOrCode implements requestBenchmark
@@ -118,9 +118,9 @@ func (b *benchmarkProofsOrCode) request(peer *peer, index int) error {
 	rand.Read(key)
 	if b.code {
 		return peer.RequestCode(0, 0, []CodeReq{{BHash: b.headHash, AccKey: key}})
-	} else {
-		return peer.RequestProofs(0, 0, []ProofReq{{BHash: b.headHash, Key: key}})
 	}
+	return peer.RequestProofs(0, 0, []ProofReq{{BHash: b.headHash, Key: key}})
+
 }
 
 // benchmarkHelperTrie implements requestBenchmark
@@ -281,8 +281,8 @@ func (pm *ProtocolManager) measure(setup *benchmarkSetup, count int) error {
 	serverMeteredPipe := &meteredPipe{rw: serverPipe}
 	var id enode.ID
 	rand.Read(id[:])
-	clientPeer := pm.newPeer(lpv2, NetworkId, p2p.NewPeer(id, "client", nil), clientMeteredPipe)
+	clientPeer := pm.newPeer(lpv2, NetworkID, p2p.NewPeer(id, "client", nil), clientMeteredPipe)
-	serverPeer := pm.newPeer(lpv2, NetworkId, p2p.NewPeer(id, "server", nil), serverMeteredPipe)
+	serverPeer := pm.newPeer(lpv2, NetworkID, p2p.NewPeer(id, "server", nil), serverMeteredPipe)
 	serverPeer.sendQueue = newExecQueue(count)
 	serverPeer.announceType = announceTypeNone
 	serverPeer.fcCosts = make(requestCostTable)

les/freeclient_test.go

@@ -51,7 +51,7 @@ func testFreeClientPool(t *testing.T, connLimit, clientCount int) {
 		peerAddress = func(i int) string {
 			return fmt.Sprintf("addr #%d", i)
 		}
-		peerId = func(i int) string {
+		peerID = func(i int) string {
 			return fmt.Sprintf("id #%d", i)
 		}
 		disconnFn = func(id string) {
@@ -67,14 +67,14 @@ func testFreeClientPool(t *testing.T, connLimit, clientCount int) {
 
 	// pool should accept new peers up to its connected limit
 	for i := 0; i < connLimit; i++ {
-		if pool.connect(peerAddress(i), peerId(i)) {
+		if pool.connect(peerAddress(i), peerID(i)) {
 			connected[i] = true
 		} else {
 			t.Fatalf("Test peer #%d rejected", i)
 		}
 	}
 	// since all accepted peers are new and should not be kicked out, the next one should be rejected
-	if pool.connect(peerAddress(connLimit), peerId(connLimit)) {
+	if pool.connect(peerAddress(connLimit), peerID(connLimit)) {
 		connected[connLimit] = true
 		t.Fatalf("Peer accepted over connected limit")
 	}
@@ -89,7 +89,7 @@ func testFreeClientPool(t *testing.T, connLimit, clientCount int) {
 			connected[i] = false
 			connTicks[i] += tickCounter
 		} else {
-			if pool.connect(peerAddress(i), peerId(i)) {
+			if pool.connect(peerAddress(i), peerID(i)) {
 				connected[i] = true
 				connTicks[i] -= tickCounter
 			}
@@ -135,7 +135,7 @@ func testFreeClientPool(t *testing.T, connLimit, clientCount int) {
 
 	// try connecting all known peers (connLimit should be filled up)
 	for i := 0; i < clientCount; i++ {
-		pool.connect(peerAddress(i), peerId(i))
+		pool.connect(peerAddress(i), peerID(i))
 	}
 	// expect pool to remember known nodes and kick out one of them to accept a new one
 	if !pool.connect("newAddr2", "newId2") {

les/handler.go

@@ -49,14 +49,22 @@ const (
 
 	ethVersion = 63 // equivalent eth version for the downloader
 
-	MaxHeaderFetch           = 192 // Amount of block headers to be fetched per retrieval request
+	// MaxHeaderFetch -  Amount of block headers to be fetched per retrieval request
-	MaxBodyFetch             = 32  // Amount of block bodies to be fetched per retrieval request
+	MaxHeaderFetch = 192
-	MaxReceiptFetch          = 128 // Amount of transaction receipts to allow fetching per request
+	// MaxBodyFetch - Amount of block bodies to be fetched per retrieval request
-	MaxCodeFetch             = 64  // Amount of contract codes to allow fetching per request
+	MaxBodyFetch = 32
-	MaxProofsFetch           = 64  // Amount of merkle proofs to be fetched per retrieval request
+	// MaxReceiptFetch - Amount of transaction receipts to allow fetching per request
-	MaxHelperTrieProofsFetch = 64  // Amount of merkle proofs to be fetched per retrieval request
+	MaxReceiptFetch = 128
-	MaxTxSend                = 64  // Amount of transactions to be send per request
+	// MaxCodeFetch - Amount of contract codes to allow fetching per request
-	MaxTxStatus              = 256 // Amount of transactions to queried per request
+	MaxCodeFetch = 64
+	// MaxProofsFetch - Amount of merkle proofs to be fetched per retrieval request
+	MaxProofsFetch = 64
+	// MaxHelperTrieProofsFetch - Amount of merkle proofs to be fetched per retrieval request
+	MaxHelperTrieProofsFetch = 64
+	// MaxTxSend - Amount of transactions to be send per request
+	MaxTxSend = 64
+	// MaxTxStatus - Amount of transactions to queried per request
+	MaxTxStatus = 256
 
 	disableClientRemovePeer = false
 )
@@ -65,6 +73,7 @@ func errResp(code errCode, format string, v ...interface{}) error {
 	return fmt.Errorf("%v - %v", code, fmt.Sprintf(format, v...))
 }
 
+// BlockChain - a blockchain
 type BlockChain interface {
 	Config() *params.ChainConfig
 	HasHeader(hash common.Hash, number uint64) bool
@@ -86,6 +95,7 @@ type txPool interface {
 	Status(hashes []common.Hash) []core.TxStatus
 }
 
+// ProtocolManager handles protocol messages and other protocol-specific tasks
 type ProtocolManager struct {
 	// Configs
 	chainConfig *params.ChainConfig
@@ -93,7 +103,7 @@ type ProtocolManager struct {
 
 	client    bool   // The indicator whether the node is light client
 	maxPeers  int    // The maximum number peers allowed to connect.
-	networkId uint64 // The identity of network.
+	networkID uint64 // The identity of network.
 
 	txpool       txPool
 	txrelay      *LesTxRelay
@@ -129,7 +139,7 @@ func NewProtocolManager(
 	chainConfig *params.ChainConfig,
 	indexerConfig *light.IndexerConfig,
 	client bool,
-	networkId uint64,
+	networkID uint64,
 	mux *event.TypeMux,
 	engine consensus.Engine,
 	peers *peerSet,
@@ -151,7 +161,7 @@ func NewProtocolManager(
 		iConfig:     indexerConfig,
 		chainDb:     chainDb,
 		odr:         odr,
-		networkId:   networkId,
+		networkID:   networkID,
 		txpool:      txpool,
 		txrelay:     txrelay,
 		serverPool:  serverPool,
@@ -194,6 +204,7 @@ func (pm *ProtocolManager) removePeer(id string) {
 	pm.peers.Unregister(id)
 }
 
+// Start starts the protocol manager and is called during node startup only
 func (pm *ProtocolManager) Start(maxPeers int) {
 	pm.maxPeers = maxPeers
 	if pm.client {
@@ -206,6 +217,7 @@ func (pm *ProtocolManager) Start(maxPeers int) {
 	}
 }
 
+// Stop stops the protocol manager and is called during node shutdown only
 func (pm *ProtocolManager) Stop() {
 	// Showing a log message. During download / process this could actually
 	// take between 5 to 10 seconds and therefor feedback is required.
@@ -236,7 +248,7 @@ func (pm *ProtocolManager) Stop() {
 // runPeer is the p2p protocol run function for the given version.
 func (pm *ProtocolManager) runPeer(version uint, p *p2p.Peer, rw p2p.MsgReadWriter) error {
 	var entry *poolEntry
-	peer := pm.newPeer(int(version), pm.networkId, p, rw)
+	peer := pm.newPeer(int(version), pm.networkID, p, rw)
 	if pm.serverPool != nil {
 		entry = pm.serverPool.connect(peer, peer.Node())
 	}

les/helper_test.go

@@ -170,7 +170,7 @@ func newTestProtocolManager(lightSync bool, blocks int, generator func(int, *cor
 	if lightSync {
 		indexConfig = light.TestClientIndexerConfig
 	}
-	pm, err := NewProtocolManager(gspec.Config, indexConfig, lightSync, NetworkId, evmux, engine, peers, chain, pool, db, odr, nil, nil, make(chan struct{}), new(sync.WaitGroup), ulcConfig, func() bool { return true })
+	pm, err := NewProtocolManager(gspec.Config, indexConfig, lightSync, NetworkID, evmux, engine, peers, chain, pool, db, odr, nil, nil, make(chan struct{}), new(sync.WaitGroup), ulcConfig, func() bool { return true })
 	if err != nil {
 		return nil, err
 	}
@@ -218,7 +218,7 @@ func newTestPeer(t *testing.T, name string, version int, pm *ProtocolManager, sh
 	var id enode.ID
 	rand.Read(id[:])
 
-	peer := pm.newPeer(version, NetworkId, p2p.NewPeer(id, name, nil), net)
+	peer := pm.newPeer(version, NetworkID, p2p.NewPeer(id, name, nil), net)
 
 	// Start the peer on a new thread
 	errc := make(chan error, 1)
@@ -255,8 +255,8 @@ func newTestPeerPair(name string, version int, pm, pm2 *ProtocolManager) (*peer,
 	var id enode.ID
 	rand.Read(id[:])
 
-	peer := pm.newPeer(version, NetworkId, p2p.NewPeer(id, name, nil), net)
+	peer := pm.newPeer(version, NetworkID, p2p.NewPeer(id, name, nil), net)
-	peer2 := pm2.newPeer(version, NetworkId, p2p.NewPeer(id, name, nil), app)
+	peer2 := pm2.newPeer(version, NetworkID, p2p.NewPeer(id, name, nil), app)
 
 	// Start the peer on a new thread
 	errc := make(chan error, 1)
@@ -285,7 +285,7 @@ func newTestPeerPair(name string, version int, pm, pm2 *ProtocolManager) (*peer,
 func (p *testPeer) handshake(t *testing.T, td *big.Int, head common.Hash, headNum uint64, genesis common.Hash) {
 	var expList keyValueList
 	expList = expList.add("protocolVersion", uint64(p.version))
-	expList = expList.add("networkId", uint64(NetworkId))
+	expList = expList.add("networkId", uint64(NetworkID))
 	expList = expList.add("headTd", td)
 	expList = expList.add("headHash", head)
 	expList = expList.add("headNum", headNum)

les/odr.go

@@ -34,6 +34,7 @@ type LesOdr struct {
 	stop                                       chan struct{}
 }
 
+// NewLesOdr - construct a new LES on demand request
 func NewLesOdr(db ethdb.Database, config *light.IndexerConfig, retriever *retrieveManager) *LesOdr {
 	return &LesOdr{
 		db:            db,
@@ -81,11 +82,17 @@ func (odr *LesOdr) IndexerConfig() *light.IndexerConfig {
 }
 
 const (
+	// MsgBlockBodies - block bodies request
 	MsgBlockBodies = iota
+	// MsgCode - code request
 	MsgCode
+	// MsgReceipts - receipts request
 	MsgReceipts
+	// MsgProofsV2 - proofs request
 	MsgProofsV2
+	// MsgHelperTrieProofs - helper trie proofs request
 	MsgHelperTrieProofs
+	// MsgTxStatus - transaction status request
 	MsgTxStatus
 )
 

les/odr_requests.go

@@ -45,6 +45,7 @@ var (
 	errUselessNodes        = errors.New("useless nodes in merkle proof nodeset")
 )
 
+// LesOdrRequest - an on-demand request
 type LesOdrRequest interface {
 	GetCost(*peer) uint64
 	CanSend(*peer) bool
@@ -52,6 +53,7 @@ type LesOdrRequest interface {
 	Validate(ethdb.Database, *Msg) error
 }
 
+// LesRequest - generate a LES on demand request from a light one
 func LesRequest(req light.OdrRequest) LesOdrRequest {
 	switch r := req.(type) {
 	case *light.BlockRequest:
@@ -93,7 +95,7 @@ func (r *BlockRequest) Request(reqID uint64, peer *peer) error {
 	return peer.RequestBodies(reqID, r.GetCost(peer), []common.Hash{r.Hash})
 }
 
-// Valid processes an ODR request reply message from the LES network
+// Validate processes an ODR request reply message from the LES network
 // returns true and stores results in memory if the message was a valid reply
 // to the request (implementation of LesOdrRequest)
 func (r *BlockRequest) Validate(db ethdb.Database, msg *Msg) error {
@@ -149,7 +151,7 @@ func (r *ReceiptsRequest) Request(reqID uint64, peer *peer) error {
 	return peer.RequestReceipts(reqID, r.GetCost(peer), []common.Hash{r.Hash})
 }
 
-// Valid processes an ODR request reply message from the LES network
+// Validate processes an ODR request reply message from the LES network
 // returns true and stores results in memory if the message was a valid reply
 // to the request (implementation of LesOdrRequest)
 func (r *ReceiptsRequest) Validate(db ethdb.Database, msg *Msg) error {
@@ -178,13 +180,14 @@ func (r *ReceiptsRequest) Validate(db ethdb.Database, msg *Msg) error {
 	return nil
 }
 
+// ProofReq - a request for a proof
 type ProofReq struct {
 	BHash       common.Hash
 	AccKey, Key []byte
 	FromLevel   uint
 }
 
-// ODR request type for state/storage trie entries, see LesOdrRequest interface
+// TrieRequest -  ODR request type for state/storage trie entries, see LesOdrRequest interface
 type TrieRequest light.TrieRequest
 
 // GetCost returns the cost of the given ODR request according to the serving
@@ -209,7 +212,7 @@ func (r *TrieRequest) Request(reqID uint64, peer *peer) error {
 	return peer.RequestProofs(reqID, r.GetCost(peer), []ProofReq{req})
 }
 
-// Valid processes an ODR request reply message from the LES network
+// Validate processes an ODR request reply message from the LES network
 // returns true and stores results in memory if the message was a valid reply
 // to the request (implementation of LesOdrRequest)
 func (r *TrieRequest) Validate(db ethdb.Database, msg *Msg) error {
@@ -233,12 +236,13 @@ func (r *TrieRequest) Validate(db ethdb.Database, msg *Msg) error {
 	return nil
 }
 
+// CodeReq - a request for contract code
 type CodeReq struct {
 	BHash  common.Hash
 	AccKey []byte
 }
 
-// ODR request type for node data (used for retrieving contract code), see LesOdrRequest interface
+// CodeRequest -  ODR request type for node data (used for retrieving contract code), see LesOdrRequest interface
 type CodeRequest light.CodeRequest
 
 // GetCost returns the cost of the given ODR request according to the serving
@@ -262,7 +266,7 @@ func (r *CodeRequest) Request(reqID uint64, peer *peer) error {
 	return peer.RequestCode(reqID, r.GetCost(peer), []CodeReq{req})
 }
 
-// Valid processes an ODR request reply message from the LES network
+// Validate processes an ODR request reply message from the LES network
 // returns true and stores results in memory if the message was a valid reply
 // to the request (implementation of LesOdrRequest)
 func (r *CodeRequest) Validate(db ethdb.Database, msg *Msg) error {
@@ -297,6 +301,7 @@ const (
 	auxHeader = 2
 )
 
+// HelperTrieReq - a request for part of a trie
 type HelperTrieReq struct {
 	Type              uint
 	TrieIdx           uint64
@@ -304,12 +309,13 @@ type HelperTrieReq struct {
 	FromLevel, AuxReq uint
 }
 
+// HelperTrieResps - response to HelperTrieReq, providing merkle proofs
 type HelperTrieResps struct { // describes all responses, not just a single one
 	Proofs  light.NodeList
 	AuxData [][]byte
 }
 
-// ODR request type for requesting headers by Canonical Hash Trie, see LesOdrRequest interface
+// ChtRequest - ODR request type for requesting headers by Canonical Hash Trie, see LesOdrRequest interface
 type ChtRequest light.ChtRequest
 
 // GetCost returns the cost of the given ODR request according to the serving
@@ -340,7 +346,7 @@ func (r *ChtRequest) Request(reqID uint64, peer *peer) error {
 	return peer.RequestHelperTrieProofs(reqID, r.GetCost(peer), []HelperTrieReq{req})
 }
 
-// Valid processes an ODR request reply message from the LES network
+// Validate processes an ODR request reply message from the LES network
 // returns true and stores results in memory if the message was a valid reply
 // to the request (implementation of LesOdrRequest)
 func (r *ChtRequest) Validate(db ethdb.Database, msg *Msg) error {
@@ -393,11 +399,12 @@ func (r *ChtRequest) Validate(db ethdb.Database, msg *Msg) error {
 	return nil
 }
 
+// BloomReq -
 type BloomReq struct {
 	BloomTrieNum, BitIdx, SectionIndex, FromLevel uint64
 }
 
-// ODR request type for requesting headers by Canonical Hash Trie, see LesOdrRequest interface
+// BloomRequest - ODR request type for requesting headers by Canonical Hash Trie, see LesOdrRequest interface
 type BloomRequest light.BloomRequest
 
 // GetCost returns the cost of the given ODR request according to the serving
@@ -436,7 +443,7 @@ func (r *BloomRequest) Request(reqID uint64, peer *peer) error {
 	return peer.RequestHelperTrieProofs(reqID, r.GetCost(peer), reqs)
 }
 
-// Valid processes an ODR request reply message from the LES network
+// Validate processes an ODR request reply message from the LES network
 // returns true and stores results in memory if the message was a valid reply
 // to the request (implementation of LesOdrRequest)
 func (r *BloomRequest) Validate(db ethdb.Database, msg *Msg) error {
@@ -493,7 +500,7 @@ func (r *TxStatusRequest) Request(reqID uint64, peer *peer) error {
 	return peer.RequestTxStatus(reqID, r.GetCost(peer), r.Hashes)
 }
 
-// Valid processes an ODR request reply message from the LES network
+// Validate processes an ODR request reply message from the LES network
 // returns true and stores results in memory if the message was a valid reply
 // to the request (implementation of LesOdrRequest)
 func (r *TxStatusRequest) Validate(db ethdb.Database, msg *Msg) error {

les/peer.go

@@ -526,7 +526,7 @@ func (p *peer) Handshake(td *big.Int, head common.Hash, headNum uint64, genesis
 		return errResp(ErrGenesisBlockMismatch, "%x (!= %x)", rGenesis[:8], genesis[:8])
 	}
 	if rNetwork != p.network {
-		return errResp(ErrNetworkIdMismatch, "%d (!= %d)", rNetwork, p.network)
+		return errResp(ErrNetworkIDMismatch, "%d (!= %d)", rNetwork, p.network)
 	}
 	if int(rVersion) != p.version {
 		return errResp(ErrProtocolVersionMismatch, "%d (!= %d)", rVersion, p.version)

les/peer_test.go

@@ -12,8 +12,8 @@ import (
 )
 
 const (
-	test_networkid   = 10
+	testNetworkID   = 10
-	protocol_version = lpv2
+	protocolVersion = lpv2
 )
 
 var (
@@ -30,7 +30,7 @@ func TestPeerHandshakeSetAnnounceTypeToAnnounceTypeSignedForTrustedPeer(t *testi
 	//peer to connect(on ulc side)
 	p := peer{
 		Peer:      p2p.NewPeer(id, "test peer", []p2p.Cap{}),
-		version:   protocol_version,
+		version:   protocolVersion,
 		isTrusted: true,
 		rw: &rwStub{
 			WriteHook: func(recvList keyValueList) {
@@ -59,7 +59,7 @@ func TestPeerHandshakeSetAnnounceTypeToAnnounceTypeSignedForTrustedPeer(t *testi
 				return l
 			},
 		},
-		network: test_networkid,
+		network: testNetworkID,
 	}
 
 	err := p.Handshake(td, hash, headNum, genesis, nil)
@@ -76,7 +76,7 @@ func TestPeerHandshakeAnnounceTypeSignedForTrustedPeersPeerNotInTrusted(t *testi
 	id := newNodeID(t).ID()
 	p := peer{
 		Peer:    p2p.NewPeer(id, "test peer", []p2p.Cap{}),
-		version: protocol_version,
+		version: protocolVersion,
 		rw: &rwStub{
 			WriteHook: func(recvList keyValueList) {
 				//checking that ulc sends to peer allowedRequests=noRequests and announceType != announceTypeSigned
@@ -104,7 +104,7 @@ func TestPeerHandshakeAnnounceTypeSignedForTrustedPeersPeerNotInTrusted(t *testi
 				return l
 			},
 		},
-		network: test_networkid,
+		network: testNetworkID,
 	}
 
 	err := p.Handshake(td, hash, headNum, genesis, nil)
@@ -123,7 +123,7 @@ func TestPeerHandshakeDefaultAllRequests(t *testing.T) {
 
 	p := peer{
 		Peer:    p2p.NewPeer(id, "test peer", []p2p.Cap{}),
-		version: protocol_version,
+		version: protocolVersion,
 		rw: &rwStub{
 			ReadHook: func(l keyValueList) keyValueList {
 				l = l.add("announceType", uint64(announceTypeSigned))
@@ -132,7 +132,7 @@ func TestPeerHandshakeDefaultAllRequests(t *testing.T) {
 				return l
 			},
 		},
-		network: test_networkid,
+		network: testNetworkID,
 	}
 
 	err := p.Handshake(td, hash, headNum, genesis, s)
@@ -153,7 +153,7 @@ func TestPeerHandshakeServerSendOnlyAnnounceRequestsHeaders(t *testing.T) {
 
 	p := peer{
 		Peer:    p2p.NewPeer(id, "test peer", []p2p.Cap{}),
-		version: protocol_version,
+		version: protocolVersion,
 		rw: &rwStub{
 			ReadHook: func(l keyValueList) keyValueList {
 				l = l.add("announceType", uint64(announceTypeSigned))
@@ -171,7 +171,7 @@ func TestPeerHandshakeServerSendOnlyAnnounceRequestsHeaders(t *testing.T) {
 				}
 			},
 		},
-		network: test_networkid,
+		network: testNetworkID,
 	}
 
 	err := p.Handshake(td, hash, headNum, genesis, s)
@@ -184,7 +184,7 @@ func TestPeerHandshakeClientReceiveOnlyAnnounceRequestsHeaders(t *testing.T) {
 
 	p := peer{
 		Peer:    p2p.NewPeer(id, "test peer", []p2p.Cap{}),
-		version: protocol_version,
+		version: protocolVersion,
 		rw: &rwStub{
 			ReadHook: func(l keyValueList) keyValueList {
 				l = l.add("flowControl/BL", uint64(0))
@@ -196,7 +196,7 @@ func TestPeerHandshakeClientReceiveOnlyAnnounceRequestsHeaders(t *testing.T) {
 				return l
 			},
 		},
-		network:   test_networkid,
+		network:   testNetworkID,
 		isTrusted: true,
 	}
 
@@ -215,7 +215,7 @@ func TestPeerHandshakeClientReturnErrorOnUselessPeer(t *testing.T) {
 
 	p := peer{
 		Peer:    p2p.NewPeer(id, "test peer", []p2p.Cap{}),
-		version: protocol_version,
+		version: protocolVersion,
 		rw: &rwStub{
 			ReadHook: func(l keyValueList) keyValueList {
 				l = l.add("flowControl/BL", uint64(0))
@@ -227,7 +227,7 @@ func TestPeerHandshakeClientReturnErrorOnUselessPeer(t *testing.T) {
 				return l
 			},
 		},
-		network: test_networkid,
+		network: testNetworkID,
 	}
 
 	err := p.Handshake(td, hash, headNum, genesis, nil)
@@ -254,8 +254,8 @@ type rwStub struct {
 
 func (s *rwStub) ReadMsg() (p2p.Msg, error) {
 	payload := keyValueList{}
-	payload = payload.add("protocolVersion", uint64(protocol_version))
+	payload = payload.add("protocolVersion", uint64(protocolVersion))
-	payload = payload.add("networkId", uint64(test_networkid))
+	payload = payload.add("networkId", uint64(testNetworkID))
 	payload = payload.add("headTd", td)
 	payload = payload.add("headHash", hash)
 	payload = payload.add("headNum", headNum)

les/protocol.go

@@ -41,12 +41,14 @@ var (
 	AdvertiseProtocolVersions = []uint{lpv2} // clients are searching for the first advertised protocol in the list
 )
 
-// Number of implemented message corresponding to different protocol versions.
+// ProtocolLengths - Number of implemented message corresponding to different protocol versions.
 var ProtocolLengths = map[uint]uint64{lpv2: 22}
 
 const (
-	NetworkId          = 1
+	// NetworkID - the network id
-	ProtocolMaxMsgSize = 10 * 1024 * 1024 // Maximum cap on the size of a protocol message
+	NetworkID = 1
+	// ProtocolMaxMsgSize - Maximum cap on the size of a protocol message
+	ProtocolMaxMsgSize = 10 * 1024 * 1024
 )
 
 // les protocol message codes
@@ -91,20 +93,35 @@ var requests = map[uint64]requestInfo{
 type errCode int
 
 const (
+	// ErrMsgTooLarge - message too large
 	ErrMsgTooLarge = iota
+	// ErrDecode - decode error
 	ErrDecode
+	// ErrInvalidMsgCode - invalid message error
 	ErrInvalidMsgCode
+	// ErrProtocolVersionMismatch - mismatched protocol version
 	ErrProtocolVersionMismatch
-	ErrNetworkIdMismatch
+	// ErrNetworkIDMismatch - wrong network id
+	ErrNetworkIDMismatch
+	// ErrGenesisBlockMismatch - incompatible genesis blocks
 	ErrGenesisBlockMismatch
+	// ErrNoStatusMsg -
 	ErrNoStatusMsg
+	// ErrExtraStatusMsg -
 	ErrExtraStatusMsg
+	// ErrSuspendedPeer -
 	ErrSuspendedPeer
+	// ErrUselessPeer -
 	ErrUselessPeer
+	// ErrRequestRejected -
 	ErrRequestRejected
+	// ErrUnexpectedResponse -
 	ErrUnexpectedResponse
+	// ErrInvalidResponse -
 	ErrInvalidResponse
+	// ErrTooManyTimeouts -
 	ErrTooManyTimeouts
+	// ErrMissingKey -
 	ErrMissingKey
 )
 
@@ -118,7 +135,7 @@ var errorToString = map[int]string{
 	ErrDecode:                  "Invalid message",
 	ErrInvalidMsgCode:          "Invalid message code",
 	ErrProtocolVersionMismatch: "Protocol version mismatch",
-	ErrNetworkIdMismatch:       "NetworkId mismatch",
+	ErrNetworkIDMismatch:       "NetworkId mismatch",
 	ErrGenesisBlockMismatch:    "Genesis block mismatch",
 	ErrNoStatusMsg:             "No status message",
 	ErrExtraStatusMsg:          "Extra status message",

les/server.go

@@ -37,6 +37,7 @@ import (
 
 const bufLimitRatio = 6000 // fixed bufLimit/MRR ratio
 
+// LesServer - a node service running a LES server
 type LesServer struct {
 	lesCommons
 
@@ -56,6 +57,7 @@ type LesServer struct {
 	priorityClientPool *priorityClientPool
 }
 
+// NewLesServer - ctor creating a LES server node service
 func NewLesServer(eth *eth.Ethereum, config *eth.Config) (*LesServer, error) {
 	quitSync := make(chan struct{})
 	pm, err := NewProtocolManager(
@@ -124,9 +126,13 @@ func NewLesServer(eth *eth.Ethereum, config *eth.Config) (*LesServer, error) {
 	}
 
 	srv.chtIndexer.Start(eth.BlockChain())
+
+	eth.GetBloomIndexer().AddChildIndexer(srv.bloomTrieIndexer)
+
 	return srv, nil
 }
 
+// APIs - the RPC APIs offered by this server
 func (s *LesServer) APIs() []rpc.API {
 	return []rpc.API{
 		{
@@ -180,12 +186,13 @@ func (s *LesServer) startEventLoop() {
 	}()
 }
 
+// Protocols - rlpx capabilities offered by this LES server
 func (s *LesServer) Protocols() []p2p.Protocol {
 	return s.makeProtocols(ServerProtocolVersions)
 }
 
 // Start starts the LES server
-func (s *LesServer) Start(srvr *p2p.Server) {
+func (s *LesServer) Start(srvr *p2p.Server) error {
 	s.maxPeers = s.config.LightPeers
 	totalRecharge := s.costTracker.totalRecharge()
 	if s.maxPeers > 0 {
@@ -225,22 +232,30 @@ func (s *LesServer) Start(srvr *p2p.Server) {
 	}
 	s.privateKey = srvr.PrivateKey
 	s.protocolManager.blockLoop()
+	return nil
 }
 
+// SetBloomBitsIndexer - adds the bloombits indexer as a child indexer to the bloomtrie indexer
 func (s *LesServer) SetBloomBitsIndexer(bloomIndexer *core.ChainIndexer) {
 	bloomIndexer.AddChildIndexer(s.bloomTrieIndexer)
 }
 
 // Stop stops the LES service
-func (s *LesServer) Stop() {
+func (s *LesServer) Stop() error {
-	s.chtIndexer.Close()
+
+	err := s.chtIndexer.Close()
+
 	// bloom trie indexer is closed by parent bloombits indexer
 	go func() {
 		<-s.protocolManager.noMorePeers
 	}()
+
 	s.freeClientPool.stop()
+
 	s.costTracker.stop()
+
 	s.protocolManager.Stop()
+	return err
 }
 
 // todo(rjl493456442) separate client and server implementation.

les/ulc_test.go

@@ -176,8 +176,8 @@ func connectPeers(full, light pairPeer, version int) (*peer, *peer, error) {
 	// Create a message pipe to communicate through
 	app, net := p2p.MsgPipe()
 
-	peerLight := full.PM.newPeer(version, NetworkId, p2p.NewPeer(light.Node.ID(), light.Name, nil), net)
+	peerLight := full.PM.newPeer(version, NetworkID, p2p.NewPeer(light.Node.ID(), light.Name, nil), net)
-	peerFull := light.PM.newPeer(version, NetworkId, p2p.NewPeer(full.Node.ID(), full.Name, nil), app)
+	peerFull := light.PM.newPeer(version, NetworkID, p2p.NewPeer(full.Node.ID(), full.Name, nil), app)
 
 	// Start the peerLight on a new thread
 	errc1 := make(chan error, 1)