les: move server pool to les/vflux/client (ethereum#22377)

* les: move serverPool to les/vflux/client

* les: add metrics

* les: moved ValueTracker inside ServerPool

* les: protect against node registration before server pool is started

* les/vflux/client: fixed tests

* les: make peer registration safe

internal/web3ext/web3ext.go

@@ -33,7 +33,7 @@ var Modules = map[string]string{
 	"swarmfs":    SwarmfsJs,
 	"txpool":     TxpoolJs,
 	"les":        LESJs,
-	"lespay":     LESPayJs,
+	"vflux":      VfluxJs,
 }
 
 const ChequebookJs = `
@@ -877,32 +877,32 @@ web3._extend({
 });
 `
 
-const LESPayJs = `
+const VfluxJs = `
 web3._extend({
-	property: 'lespay',
+	property: 'vflux',
 	methods:
 	[
 		new web3._extend.Method({
 			name: 'distribution',
-			call: 'lespay_distribution',
+			call: 'vflux_distribution',
 			params: 2
 		}),
 		new web3._extend.Method({
 			name: 'timeout',
-			call: 'lespay_timeout',
+			call: 'vflux_timeout',
 			params: 2
 		}),
 		new web3._extend.Method({
 			name: 'value',
-			call: 'lespay_value',
+			call: 'vflux_value',
 			params: 2
 		}),
 	],
 	properties:
 	[
 		new web3._extend.Property({
 			name: 'requestStats',
-			getter: 'lespay_requestStats'
+			getter: 'vflux_requestStats'
 		}),
 	]
 });

les/client.go

@@ -57,8 +57,7 @@ type LightEthereum struct {
 	handler        *clientHandler
 	txPool         *light.TxPool
 	blockchain     *light.LightChain
-	serverPool     *serverPool
-	valueTracker   *vfc.ValueTracker
+	serverPool     *vfc.ServerPool
 	dialCandidates enode.Iterator
 	pruner         *pruner
 
@@ -109,17 +108,14 @@ func New(stack *node.Node, config *ethconfig.Config) (*LightEthereum, error) {
 		engine:         ethconfig.CreateConsensusEngine(stack, chainConfig, &config.Ethash, nil, false, chainDb),
 		bloomRequests:  make(chan chan *bloombits.Retrieval),
 		bloomIndexer:   core.NewBloomIndexer(chainDb, params.BloomBitsBlocksClient, params.HelperTrieConfirmations),
-		valueTracker:   vfc.NewValueTracker(lesDb, &mclock.System{}, requestList, time.Minute, 1/float64(time.Hour), 1/float64(time.Hour*100), 1/float64(time.Hour*1000)),
 		p2pServer:      stack.Server(),
 		p2pConfig:      &stack.Config().P2P,
 	}
-	peers.subscribe((*vtSubscription)(leth.valueTracker))
 
-	leth.serverPool = newServerPool(lesDb, []byte("serverpool:"), leth.valueTracker, time.Second, nil, &mclock.System{}, config.UltraLightServers)
-	peers.subscribe(leth.serverPool)
-	leth.dialCandidates = leth.serverPool.dialIterator
+	leth.serverPool, leth.dialCandidates = vfc.NewServerPool(lesDb, []byte("serverpool:"), time.Second, nil, &mclock.System{}, config.UltraLightServers, requestList)
+	leth.serverPool.AddMetrics(suggestedTimeoutGauge, totalValueGauge, serverSelectableGauge, serverConnectedGauge, sessionValueMeter, serverDialedMeter)
 
-	leth.retriever = newRetrieveManager(peers, leth.reqDist, leth.serverPool.getTimeout)
+	leth.retriever = newRetrieveManager(peers, leth.reqDist, leth.serverPool.GetTimeout)
 	leth.relay = newLesTxRelay(peers, leth.retriever)
 
 	leth.odr = NewLesOdr(chainDb, light.DefaultClientIndexerConfig, leth.peers, leth.retriever)
@@ -193,23 +189,6 @@ func New(stack *node.Node, config *ethconfig.Config) (*LightEthereum, error) {
 	return leth, nil
 }
 
-// vtSubscription implements serverPeerSubscriber
-type vtSubscription vfc.ValueTracker
-
-// registerPeer implements serverPeerSubscriber
-func (v *vtSubscription) registerPeer(p *serverPeer) {
-	vt := (*vfc.ValueTracker)(v)
-	p.setValueTracker(vt, vt.Register(p.ID()))
-	p.updateVtParams()
-}
-
-// unregisterPeer implements serverPeerSubscriber
-func (v *vtSubscription) unregisterPeer(p *serverPeer) {
-	vt := (*vfc.ValueTracker)(v)
-	vt.Unregister(p.ID())
-	p.setValueTracker(nil, nil)
-}
-
 type LightDummyAPI struct{}
 
 // Etherbase is the address that mining rewards will be send to
@@ -266,7 +245,7 @@ func (s *LightEthereum) APIs() []rpc.API {
 		}, {
 			Namespace: "vflux",
 			Version:   "1.0",
-			Service:   vfc.NewPrivateClientAPI(s.valueTracker),
+			Service:   s.serverPool.API(),
 			Public:    false,
 		},
 	}...)
@@ -302,8 +281,8 @@ func (s *LightEthereum) Start() error {
 	if err != nil {
 		return err
 	}
-	s.serverPool.addSource(discovery)
-	s.serverPool.start()
+	s.serverPool.AddSource(discovery)
+	s.serverPool.Start()
 	// Start bloom request workers.
 	s.wg.Add(bloomServiceThreads)
 	s.startBloomHandlers(params.BloomBitsBlocksClient)
@@ -316,8 +295,7 @@ func (s *LightEthereum) Start() error {
 // Ethereum protocol.
 func (s *LightEthereum) Stop() error {
 	close(s.closeCh)
-	s.serverPool.stop()
-	s.valueTracker.Stop()
+	s.serverPool.Stop()
 	s.peers.close()
 	s.reqDist.close()
 	s.odr.Stop()

les/client_handler.go

@@ -114,11 +114,25 @@ func (h *clientHandler) handle(p *serverPeer) error {
 		p.Log().Debug("Light Ethereum handshake failed", "err", err)
 		return err
 	}
+	// Register peer with the server pool
+	if h.backend.serverPool != nil {
+		if nvt, err := h.backend.serverPool.RegisterNode(p.Node()); err == nil {
+			p.setValueTracker(nvt)
+			p.updateVtParams()
+			defer func() {
+				p.setValueTracker(nil)
+				h.backend.serverPool.UnregisterNode(p.Node())
+			}()
+		} else {
+			return err
+		}
+	}
 	// Register the peer locally
 	if err := h.backend.peers.register(p); err != nil {
 		p.Log().Error("Light Ethereum peer registration failed", "err", err)
 		return err
 	}
+
 	serverConnectionGauge.Update(int64(h.backend.peers.len()))
 
 	connectedAt := mclock.Now()

les/peer.go

@@ -349,7 +349,6 @@ type serverPeer struct {
 
 	fcServer         *flowcontrol.ServerNode // Client side mirror token bucket.
 	vtLock           sync.Mutex
-	valueTracker     *vfc.ValueTracker
 	nodeValueTracker *vfc.NodeValueTracker
 	sentReqs         map[uint64]sentReqEntry
 
@@ -676,9 +675,8 @@ func (p *serverPeer) Handshake(genesis common.Hash, forkid forkid.ID, forkFilter
 
 // setValueTracker sets the value tracker references for connected servers. Note that the
 // references should be removed upon disconnection by setValueTracker(nil, nil).
-func (p *serverPeer) setValueTracker(vt *vfc.ValueTracker, nvt *vfc.NodeValueTracker) {
+func (p *serverPeer) setValueTracker(nvt *vfc.NodeValueTracker) {
 	p.vtLock.Lock()
-	p.valueTracker = vt
 	p.nodeValueTracker = nvt
 	if nvt != nil {
 		p.sentReqs = make(map[uint64]sentReqEntry)
@@ -705,7 +703,7 @@ func (p *serverPeer) updateVtParams() {
 			}
 		}
 	}
-	p.valueTracker.UpdateCosts(p.nodeValueTracker, reqCosts)
+	p.nodeValueTracker.UpdateCosts(reqCosts)
 }
 
 // sentReqEntry remembers sent requests and their sending times
@@ -732,7 +730,6 @@ func (p *serverPeer) answeredRequest(id uint64) {
 	}
 	e, ok := p.sentReqs[id]
 	delete(p.sentReqs, id)
-	vt := p.valueTracker
 	nvt := p.nodeValueTracker
 	p.vtLock.Unlock()
 	if !ok {
@@ -752,7 +749,7 @@ func (p *serverPeer) answeredRequest(id uint64) {
 		vtReqs[1] = vfc.ServedRequest{ReqType: uint32(m.rest), Amount: e.amount - 1}
 	}
 	dt := time.Duration(mclock.Now() - e.at)
-	vt.Served(nvt, vtReqs[:reqCount], dt)
+	nvt.Served(vtReqs[:reqCount], dt)
 }
 
 // clientPeer represents each node to which the les server is connected.

les/vflux/client/queueiterator_test.go

@@ -26,17 +26,6 @@ import (
 	"github.com/ethereum/go-ethereum/p2p/nodestate"
 )
 
-func testNodeID(i int) enode.ID {
-	return enode.ID{42, byte(i % 256), byte(i / 256)}
-}
-
-func testNodeIndex(id enode.ID) int {
-	if id[0] != 42 {
-		return -1
-	}
-	return int(id[1]) + int(id[2])*256
-}
-
 func testNode(i int) *enode.Node {
 	return enode.SignNull(new(enr.Record), testNodeID(i))
 }