multi: no trades while blockchain syncing

Client waits for blockchain sync to complete.
Server waits to start markets receiving new orders, and warns if fee estimation isn't ready.

client/asset/btc/btc.go

@@ -17,6 +17,7 @@ import (
 	"strconv"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"decred.org/dcrdex/client/asset"
@@ -39,6 +40,7 @@ const (
 	// rpcclient.Client's GetBlockVerboseTx appears to be busted.
 	methodGetBlockVerboseTx = "getblock"
 	methodGetNetworkInfo    = "getnetworkinfo"
+	methodGetBlockchainInfo = "getblockchaininfo"
 	// BipID is the BIP-0044 asset ID.
 	BipID = 0
 
@@ -348,6 +350,7 @@ type ExchangeWallet struct {
 	log               dex.Logger
 	symbol            string
 	tipChange         func(error)
+	tipAtConnect      int64
 	minNetworkVersion uint64
 	fallbackFeeRate   uint64
 	redeemConfTarget  uint64
@@ -519,6 +522,7 @@ func (btc *ExchangeWallet) Connect(ctx context.Context) (*sync.WaitGroup, error)
 	if err != nil {
 		return nil, fmt.Errorf("error initializing best block for %s: %v", btc.symbol, err)
 	}
+	atomic.StoreInt64(&btc.tipAtConnect, btc.currentTip.height)
 	var wg sync.WaitGroup
 	wg.Add(1)
 	go func() {
@@ -541,6 +545,41 @@ func (btc *ExchangeWallet) shutdown() {
 	btc.findRedemptionMtx.Unlock()
 }
 
+// getBlockchainInfoResult models the data returned from the getblockchaininfo
+// command.
+type getBlockchainInfoResult struct {
+	Blocks               int64  `json:"blocks"`
+	Headers              int64  `json:"headers"`
+	BestBlockHash        string `json:"bestblockhash"`
+	InitialBlockDownload bool   `json:"initialblockdownload"`
+}
+
+// getBlockchainInfo sends the getblockchaininfo request and returns the result.
+func (btc *ExchangeWallet) getBlockchainInfo() (*getBlockchainInfoResult, error) {
+	chainInfo := new(getBlockchainInfoResult)
+	err := btc.wallet.call(methodGetBlockchainInfo, nil, chainInfo)
+	if err != nil {
+		return nil, err
+	}
+	return chainInfo, nil
+}
+
+// SyncStatus is information about the blockchain sync status.
+func (btc *ExchangeWallet) SyncStatus() (bool, float32, error) {
+	chainInfo, err := btc.getBlockchainInfo()
+	if err != nil {
+		return false, 0, fmt.Errorf("getblockchaininfo error: %w", err)
+	}
+	toGo := chainInfo.Headers - chainInfo.Blocks
+	if chainInfo.InitialBlockDownload || toGo > 1 {
+		ogTip := atomic.LoadInt64(&btc.tipAtConnect)
+		totalToSync := chainInfo.Headers - ogTip
+		progress := 1 - (float32(toGo) / float32(totalToSync))
+		return false, progress, nil
+	}
+	return true, 1, nil
+}
+
 // Balance returns the total available funds in the wallet. Part of the
 // asset.Wallet interface.
 func (btc *ExchangeWallet) Balance() (*asset.Balance, error) {

client/asset/btc/btc_test.go

@@ -2077,3 +2077,46 @@ func testSendEdges(t *testing.T, segwit bool) {
 		}
 	}
 }
+
+func TestSyncStatus(t *testing.T) {
+	wallet, node, shutdown := tNewWallet(false)
+	defer shutdown()
+	node.rawRes[methodGetBlockchainInfo] = mustMarshal(t, &getBlockchainInfoResult{
+		Headers: 100,
+		Blocks:  99,
+	})
+
+	synced, progress, err := wallet.SyncStatus()
+	if err != nil {
+		t.Fatalf("SyncStatus error (synced expected): %v", err)
+	}
+	if !synced {
+		t.Fatalf("synced = false for 1 block to go")
+	}
+	if progress < 1 {
+		t.Fatalf("progress not complete when loading last block")
+	}
+
+	node.rawErr[methodGetBlockchainInfo] = tErr
+	_, _, err = wallet.SyncStatus()
+	if err == nil {
+		t.Fatalf("SyncStatus error not propagated")
+	}
+	node.rawErr[methodGetBlockchainInfo] = nil
+
+	wallet.tipAtConnect = 100
+	node.rawRes[methodGetBlockchainInfo] = mustMarshal(t, &getBlockchainInfoResult{
+		Headers: 200,
+		Blocks:  150,
+	})
+	synced, progress, err = wallet.SyncStatus()
+	if err != nil {
+		t.Fatalf("SyncStatus error (half-synced): %v", err)
+	}
+	if synced {
+		t.Fatalf("synced = true for 50 blocks to go")
+	}
+	if progress > 0.500001 || progress < 0.4999999 {
+		t.Fatalf("progress out of range. Expected 0.5, got %.2f", progress)
+	}
+}

client/asset/dcr/dcr.go

@@ -19,6 +19,7 @@ import (
 	"strconv"
 	"strings"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"decred.org/dcrdex/client/asset"
@@ -131,6 +132,7 @@ var (
 // rpcClient is an rpcclient.Client, or a stub for testing.
 type rpcClient interface {
 	EstimateSmartFee(confirmations int64, mode chainjson.EstimateSmartFeeMode) (float64, error)
+	GetBlockChainInfo() (*chainjson.GetBlockChainInfoResult, error)
 	SendRawTransaction(tx *wire.MsgTx, allowHighFees bool) (*chainhash.Hash, error)
 	GetTxOut(txHash *chainhash.Hash, index uint32, mempool bool) (*chainjson.GetTxOutResult, error)
 	GetBalanceMinConf(account string, minConfirms int) (*walletjson.GetBalanceResult, error)
@@ -352,6 +354,7 @@ type ExchangeWallet struct {
 	log              dex.Logger
 	acct             string
 	tipChange        func(error)
+	tipAtConnect     int64
 	fallbackFeeRate  uint64
 	redeemConfTarget uint64
 	useSplitTx       bool
@@ -521,6 +524,7 @@ func (dcr *ExchangeWallet) Connect(ctx context.Context) (*sync.WaitGroup, error)
 	if err != nil {
 		return nil, fmt.Errorf("error initializing best block for DCR: %v", err)
 	}
+	atomic.StoreInt64(&dcr.tipAtConnect, dcr.currentTip.height)
 
 	dcr.log.Infof("Connected to dcrwallet (JSON-RPC API v%s) proxying dcrd (JSON-RPC API v%s) on %v",
 		walletSemver, nodeSemver, curnet)
@@ -1847,6 +1851,22 @@ func (dcr *ExchangeWallet) shutdown() {
 	}
 }
 
+// SyncStatus is information about the blockchain sync status.
+func (dcr *ExchangeWallet) SyncStatus() (bool, float32, error) {
+	chainInfo, err := dcr.node.GetBlockChainInfo()
+	if err != nil {
+		return false, 0, fmt.Errorf("getblockchaininfo error: %w", err)
+	}
+	toGo := chainInfo.Headers - chainInfo.Blocks
+	if chainInfo.InitialBlockDownload || toGo > 1 {
+		ogTip := atomic.LoadInt64(&dcr.tipAtConnect)
+		totalToSync := chainInfo.Headers - ogTip
+		progress := 1 - (float32(toGo) / float32(totalToSync))
+		return false, progress, nil
+	}
+	return true, 1, nil
+}
+
 // Combines the RPC type with the spending input information.
 type compositeUTXO struct {
 	rpc   walletjson.ListUnspentResult

client/asset/dcr/dcr_test.go

@@ -173,41 +173,43 @@ func signFunc(msgTx *wire.MsgTx, scriptSize int) (*wire.MsgTx, bool, error) {
 }
 
 type tRPCClient struct {
-	sendRawHash    *chainhash.Hash
-	sendRawErr     error
-	sentRawTx      *wire.MsgTx
-	txOutRes       map[outPoint]*chainjson.GetTxOutResult
-	txOutErr       error
-	bestBlockErr   error
-	mempool        []*chainhash.Hash
-	mempoolErr     error
-	rawTx          *chainjson.TxRawResult
-	rawTxErr       error
-	unspent        []walletjson.ListUnspentResult
-	unspentErr     error
-	balanceResult  *walletjson.GetBalanceResult
-	balanceErr     error
-	lockUnspentErr error
-	changeAddr     dcrutil.Address
-	changeAddrErr  error
-	newAddr        dcrutil.Address
-	newAddrErr     error
-	signFunc       func(tx *wire.MsgTx) (*wire.MsgTx, bool, error)
-	privWIF        *dcrutil.WIF
-	privWIFErr     error
-	walletTx       *walletjson.GetTransactionResult
-	walletTxErr    error
-	lockErr        error
-	passErr        error
-	disconnected   bool
-	rawRes         map[string]json.RawMessage
-	rawErr         map[string]error
-	blockchainMtx  sync.RWMutex
-	verboseBlocks  map[string]*chainjson.GetBlockVerboseResult
-	mainchain      map[int64]*chainhash.Hash
-	lluCoins       []walletjson.ListUnspentResult // Returned from ListLockUnspent
-	lockedCoins    []*wire.OutPoint               // Last submitted to LockUnspent
-	listLockedErr  error
+	sendRawHash       *chainhash.Hash
+	sendRawErr        error
+	sentRawTx         *wire.MsgTx
+	txOutRes          map[outPoint]*chainjson.GetTxOutResult
+	txOutErr          error
+	bestBlockErr      error
+	mempool           []*chainhash.Hash
+	mempoolErr        error
+	rawTx             *chainjson.TxRawResult
+	rawTxErr          error
+	unspent           []walletjson.ListUnspentResult
+	unspentErr        error
+	balanceResult     *walletjson.GetBalanceResult
+	balanceErr        error
+	lockUnspentErr    error
+	changeAddr        dcrutil.Address
+	changeAddrErr     error
+	newAddr           dcrutil.Address
+	newAddrErr        error
+	signFunc          func(tx *wire.MsgTx) (*wire.MsgTx, bool, error)
+	privWIF           *dcrutil.WIF
+	privWIFErr        error
+	walletTx          *walletjson.GetTransactionResult
+	walletTxErr       error
+	lockErr           error
+	passErr           error
+	disconnected      bool
+	rawRes            map[string]json.RawMessage
+	rawErr            map[string]error
+	blockchainMtx     sync.RWMutex
+	verboseBlocks     map[string]*chainjson.GetBlockVerboseResult
+	mainchain         map[int64]*chainhash.Hash
+	lluCoins          []walletjson.ListUnspentResult // Returned from ListLockUnspent
+	lockedCoins       []*wire.OutPoint               // Last submitted to LockUnspent
+	listLockedErr     error
+	blockchainInfo    *chainjson.GetBlockChainInfoResult
+	blockchainInfoErr error
 }
 
 func defaultSignFunc(tx *wire.MsgTx) (*wire.MsgTx, bool, error) { return tx, true, nil }
@@ -236,6 +238,10 @@ func (c *tRPCClient) EstimateSmartFee(confirmations int64, mode chainjson.Estima
 	return optimalRate, nil // optimalFeeRate: 22 atoms/byte = 0.00022 DCR/KB * 1e8 atoms/DCR * 1e-3 KB/Byte
 }
 
+func (c *tRPCClient) GetBlockChainInfo() (*chainjson.GetBlockChainInfoResult, error) {
+	return c.blockchainInfo, c.blockchainInfoErr
+}
+
 func (c *tRPCClient) SendRawTransaction(tx *wire.MsgTx, allowHighFees bool) (*chainhash.Hash, error) {
 	c.sentRawTx = tx
 	if c.sendRawErr == nil && c.sendRawHash == nil {
@@ -1828,3 +1834,46 @@ func TestSendEdges(t *testing.T) {
 		}
 	}
 }
+
+func TestSyncStatus(t *testing.T) {
+	wallet, node, shutdown := tNewWallet()
+	defer shutdown()
+	node.blockchainInfo = &chainjson.GetBlockChainInfoResult{
+		Headers: 100,
+		Blocks:  99,
+	}
+
+	synced, progress, err := wallet.SyncStatus()
+	if err != nil {
+		t.Fatalf("SyncStatus error (synced expected): %v", err)
+	}
+	if !synced {
+		t.Fatalf("synced = false for 1 block to go")
+	}
+	if progress < 1 {
+		t.Fatalf("progress not complete when loading last block")
+	}
+
+	node.blockchainInfoErr = tErr
+	_, _, err = wallet.SyncStatus()
+	if err == nil {
+		t.Fatalf("SyncStatus error not propagated")
+	}
+	node.blockchainInfoErr = nil
+
+	wallet.tipAtConnect = 100
+	node.blockchainInfo = &chainjson.GetBlockChainInfoResult{
+		Headers: 200,
+		Blocks:  150,
+	}
+	synced, progress, err = wallet.SyncStatus()
+	if err != nil {
+		t.Fatalf("SyncStatus error (half-synced): %v", err)
+	}
+	if synced {
+		t.Fatalf("synced = true for 50 blocks to go")
+	}
+	if progress > 0.500001 || progress < 0.4999999 {
+		t.Fatalf("progress out of range. Expected 0.5, got %.2f", progress)
+	}
+}

client/asset/interface.go

@@ -150,6 +150,8 @@ type Wallet interface {
 	Withdraw(address string, value uint64) (Coin, error)
 	// ValidateSecret checks that the secret hashes to the secret hash.
 	ValidateSecret(secret, secretHash []byte) bool
+	// SyncStatus is information about the blockchain sync status.
+	SyncStatus() (synced bool, progress float32, err error)
 }
 
 // Balance is categorized information about a wallet's balance.