les, les/flowcontrol: implement LES/3 (#19329)

les, les/flowcontrol: implement LES/3

les/handler_test.go

@@ -24,6 +24,7 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/mclock"
 	"github.com/ethereum/go-ethereum/consensus/ethash"
 	"github.com/ethereum/go-ethereum/core"
 	"github.com/ethereum/go-ethereum/core/rawdb"
@@ -438,7 +439,7 @@ func TestTransactionStatusLes2(t *testing.T) {
 	config.Journal = ""
 	txpool := core.NewTxPool(config, params.TestChainConfig, chain)
 	pm.txpool = txpool
-	peer, _ := newTestPeer(t, "peer", 2, pm, true)
+	peer, _ := newTestPeer(t, "peer", 2, pm, true, 0)
 	defer peer.close()
 
 	var reqID uint64
@@ -519,3 +520,51 @@ func TestTransactionStatusLes2(t *testing.T) {
 	test(tx1, false, light.TxStatus{Status: core.TxStatusPending})
 	test(tx2, false, light.TxStatus{Status: core.TxStatusPending})
 }
+
+func TestStopResumeLes3(t *testing.T) {
+	db := rawdb.NewMemoryDatabase()
+	clock := &mclock.Simulated{}
+	testCost := testBufLimit / 10
+	pm, err := newTestProtocolManager(false, 0, nil, nil, nil, db, nil, testCost, clock)
+	if err != nil {
+		t.Fatalf("Failed to create protocol manager: %v", err)
+	}
+	peer, _ := newTestPeer(t, "peer", 3, pm, true, testCost)
+	defer peer.close()
+
+	expBuf := testBufLimit
+	var reqID uint64
+
+	req := func() {
+		reqID++
+		sendRequest(peer.app, GetBlockHeadersMsg, reqID, testCost, &getBlockHeadersData{Origin: hashOrNumber{Hash: common.Hash{1}}, Amount: 1})
+	}
+
+	for i := 1; i <= 5; i++ {
+		// send requests while we still have enough buffer and expect a response
+		for expBuf >= testCost {
+			req()
+			expBuf -= testCost
+			if err := expectResponse(peer.app, BlockHeadersMsg, reqID, expBuf, nil); err != nil {
+				t.Errorf("expected response and failed: %v", err)
+			}
+		}
+		// send some more requests in excess and expect a single StopMsg
+		c := i
+		for c > 0 {
+			req()
+			c--
+		}
+		if err := p2p.ExpectMsg(peer.app, StopMsg, nil); err != nil {
+			t.Errorf("expected StopMsg and failed: %v", err)
+		}
+		// wait until the buffer is recharged by half of the limit
+		wait := testBufLimit / testBufRecharge / 2
+		clock.Run(time.Millisecond * time.Duration(wait))
+		// expect a ResumeMsg with the partially recharged buffer value
+		expBuf += testBufRecharge * wait
+		if err := p2p.ExpectMsg(peer.app, ResumeMsg, expBuf); err != nil {
+			t.Errorf("expected ResumeMsg and failed: %v", err)
+		}
+	}
+}