Importxpub (#27)

config.go

@@ -11,6 +11,7 @@ import (
 	"strings"
 
 	"github.com/decred/dcrd/dcrutil/v3"
+	"github.com/decred/dcrd/hdkeychain/v3"
 	flags "github.com/jessevdk/go-flags"
 )
 
@@ -30,6 +31,7 @@ type config struct {
 	Listen     string  `long:"listen" ini-name:"listen" description:"The ip:port to listen for API requests."`
 	LogLevel   string  `long:"loglevel" ini-name:"loglevel" description:"Logging level." choice:"trace" choice:"debug" choice:"info" choice:"warn" choice:"error" choice:"critical"`
 	Network    string  `long:"network" ini-name:"network" description:"Decred network to use." choice:"testnet" choice:"mainnet" choice:"simnet"`
+	FeeXPub    string  `long:"feexpub" ini-name:"feexpub" description:"cold wallet xpub used for collecting fees"`
 	VSPFee     float64 `long:"vspfee" ini-name:"vspfee" description:"The fee percentage charged for VSP use. eg. 0.01 (1%), 0.05 (5%)."`
 	HomeDir    string  `long:"homedir" ini-name:"homedir" no-ini:"true" description:"Path to application home directory. Used for storing VSP database and logs."`
 	ConfigFile string  `long:"configfile" ini-name:"configfile" no-ini:"true" description:"Path to configuration file."`
@@ -279,5 +281,11 @@ func loadConfig() (*config, error) {
 	// Set the database path
 	cfg.dbPath = filepath.Join(dataDir, "vsp.db")
 
+	// Validate the cold wallet xpub.
+	_, err = hdkeychain.NewKeyFromString(cfg.FeeXPub, cfg.netParams.Params)
+	if err != nil {
+		return nil, err
+	}
+
 	return &cfg, nil
 }

go.mod

@@ -9,6 +9,7 @@ require (
 	github.com/decred/dcrd/chaincfg/v3 v3.0.0-20200511175520-d08cb3f72b3b
 	github.com/decred/dcrd/dcrec v1.0.0
 	github.com/decred/dcrd/dcrutil/v3 v3.0.0-20200517213104-6ade94486839
+	github.com/decred/dcrd/hdkeychain/v3 v3.0.0-20200421213827-b60c60ffe98b
 	github.com/decred/dcrd/rpc/jsonrpc/types/v2 v2.0.0
 	github.com/decred/dcrd/txscript/v3 v3.0.0-20200511175520-d08cb3f72b3b
 	github.com/decred/dcrd/wire v1.3.0

go.sum

@@ -70,6 +70,7 @@ github.com/decred/dcrd/dcrutil/v3 v3.0.0-20200517213104-6ade94486839 h1:1re/l3jv
 github.com/decred/dcrd/dcrutil/v3 v3.0.0-20200517213104-6ade94486839/go.mod h1:85NtF/fmqL2UDf0/gLhTHG/m/0HQHwG+erQKkwWW27A=
 github.com/decred/dcrd/gcs/v2 v2.0.0/go.mod h1:3XjKcrtvB+r2ezhIsyNCLk6dRnXRJVyYmsd1P3SkU3o=
 github.com/decred/dcrd/gcs/v2 v2.0.2-0.20200312171759-0a8cc56a776e/go.mod h1:JJGd1m0DrFgV4J2J8HKNB9YVkM06ewQHT6iINis39Z4=
+github.com/decred/dcrd/hdkeychain/v3 v3.0.0-20200421213827-b60c60ffe98b h1:pfhggbZaR/h4mjHwMMgCl4+UnstAssVA7FEezvMKCQo=
 github.com/decred/dcrd/hdkeychain/v3 v3.0.0-20200421213827-b60c60ffe98b/go.mod h1:qKN0WzeSEEZ4fUBsTwKzOPkLP7GqSM6jBUm5Auq9mrM=
 github.com/decred/dcrd/rpc/jsonrpc/types/v2 v2.0.0 h1:uyvwjO+90KHxZIIztobB9cG+qVSHhCT+aGSiZF1vGAg=
 github.com/decred/dcrd/rpc/jsonrpc/types/v2 v2.0.0/go.mod h1:c5S+PtQWNIA2aUakgrLhrlopkMadcOv51dWhCEdo49c=

main.go

@@ -53,7 +53,7 @@ func run(ctx context.Context) error {
 
 	// Create dcrwallet RPC client.
 	walletRPC := rpc.Setup(ctx, &shutdownWg, cfg.WalletUser, cfg.WalletPass, cfg.WalletHost, cfg.dcrwCert)
-	_, err = walletRPC()
+	walletClient, err := walletRPC()
 	if err != nil {
 		log.Errorf("dcrwallet RPC error: %v", err)
 		requestShutdown()
@@ -68,6 +68,36 @@ func run(ctx context.Context) error {
 		shutdownWg.Wait()
 		return err
 	}
+  
+	// Get the masterpubkey from the fees account, if it exists, and make
+	// sure it matches the configuration.
+	var existingXPub string
+	err = walletClient.Call(ctx, "getmasterpubkey", &existingXPub, "fees")
+	if err != nil {
+		// TODO - ignore account not found
+		log.Errorf("dcrwallet RPC error: %v", err)
+		requestShutdown()
+		shutdownWg.Wait()
+		return err
+	}
+
+
+		// account exists - make sure it matches the configuration.
+		if existingXPub != cfg.FeeXPub {
+			log.Errorf("fees account xpub differs: %s != %s", existingXPub, cfg.FeeXPub)
+			requestShutdown()
+			shutdownWg.Wait()
+			return err
+	} else {
+		// account does not exist - import xpub from configuration.
+		if err = walletClient.Call(ctx, "importxpub", nil, "fees"); err != nil {
+			log.Errorf("failed to import xpub: %v", err)
+			requestShutdown()
+			shutdownWg.Wait()
+			return err
+		}
+ }
+
 	// Create and start webapi server.
 	apiCfg := webapi.Config{
 		SignKey:   signKey,