Add new --createtemp flag to btcwallet.

The createtemp flag is used to create a temporary simnet wallet for
use with btcsim or other testing suites.

The flag only works if the datadir and network to use it on (simnet)
are specified.

After starting btcwallet with the flag, the wallet immediately opens
and is functional.

config.go

@@ -58,6 +58,7 @@ var (
 type config struct {
 	ShowVersion      bool     `short:"V" long:"version" description:"Display version information and exit"`
 	Create           bool     `long:"create" description:"Create the wallet if it does not exist"`
+	CreateTemp       bool     `long:"createtemp" description:"Create a temporary simulation wallet (pass=password) in the data directory indicated; must call with --datadir"`
 	CAFile           string   `long:"cafile" description:"File containing root certificates to authenticate a TLS connections with btcd"`
 	RPCConnect       string   `short:"c" long:"rpcconnect" description:"Hostname/IP and port of btcd RPC server to connect to (default localhost:18334, mainnet: localhost:8334, simnet: localhost:18556)"`
 	DebugLevel       string   `short:"d" long:"debuglevel" description:"Logging level {trace, debug, info, warn, error, critical}"`
@@ -366,10 +367,57 @@ func loadConfig() (*config, []string, error) {
 		return nil, nil, err
 	}
 
+	// Exit if you try to use a simulation wallet with a standard
+	// data directory.
+	if cfg.DataDir == defaultDataDir && cfg.CreateTemp {
+		fmt.Fprintln(os.Stderr, "Tried to create a temporary simulation "+
+			"wallet, but failed to specify data directory!")
+		os.Exit(0)
+	}
+
+	// Exit if you try to use a simulation wallet on anything other than
+	// simnet or testnet3.
+	if !cfg.SimNet && cfg.CreateTemp {
+		fmt.Fprintln(os.Stderr, "Tried to create a temporary simulation "+
+			"wallet for network other than simnet!")
+		os.Exit(0)
+	}
+
 	// Ensure the wallet exists or create it when the create flag is set.
 	netDir := networkDir(cfg.DataDir, activeNet.Params)
 	dbPath := filepath.Join(netDir, walletDbName)
-	if cfg.Create {
+
+	if cfg.CreateTemp && cfg.Create {
+		err := fmt.Errorf("The flags --create and --createtemp can not " +
+			"be specified together. Use --help for more information.")
+		fmt.Fprintln(os.Stderr, err)
+		return nil, nil, err
+	}
+
+	if cfg.CreateTemp {
+		tempWalletExists := false
+
+		if fileExists(dbPath) {
+			str := fmt.Sprintf("The wallet already exists. Loading this " +
+				"wallet instead.")
+			fmt.Fprintln(os.Stdout, str)
+			tempWalletExists = true
+		}
+
+		// Ensure the data directory for the network exists.
+		if err := checkCreateDir(netDir); err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			return nil, nil, err
+		}
+
+		if !tempWalletExists {
+			// Perform the initial wallet creation wizard.
+			if err := createSimulationWallet(&cfg); err != nil {
+				fmt.Fprintln(os.Stderr, "Unable to create wallet:", err)
+				return nil, nil, err
+			}
+		}
+	} else if cfg.Create {
 		// Error if the create flag is set and the wallet already
 		// exists.
 		if fileExists(dbPath) {
@@ -392,7 +440,6 @@ func loadConfig() (*config, []string, error) {
 
 		// Created successfully, so exit now with success.
 		os.Exit(0)
-
 	} else if !fileExists(dbPath) {
 		var err error
 		keystorePath := filepath.Join(netDir, keystore.Filename)

walletsetup.go

@@ -438,3 +438,49 @@ func createWallet(cfg *config) error {
 	fmt.Println("The wallet has been created successfully.")
 	return nil
 }
+
+// createSimulationWallet is intended to be called from the rpcclient
+// and used to create a wallet for actors involved in simulations.
+func createSimulationWallet(cfg *config) error {
+	// Simulation wallet password is 'password'.
+	privPass := []byte("password")
+
+	// Public passphrase is the default.
+	pubPass := []byte(defaultPubPassphrase)
+
+	// Generate a random seed.
+	seed, err := hdkeychain.GenerateSeed(hdkeychain.RecommendedSeedLen)
+	if err != nil {
+		return err
+	}
+
+	netDir := networkDir(cfg.DataDir, activeNet.Params)
+
+	// Create the wallet.
+	dbPath := filepath.Join(netDir, walletDbName)
+	fmt.Println("Creating the wallet...")
+
+	// Create the wallet database backed by bolt db.
+	db, err := walletdb.Create("bdb", dbPath)
+	if err != nil {
+		return err
+	}
+	defer db.Close()
+
+	// Create the address manager.
+	waddrmgrNamespace, err := db.Namespace(waddrmgrNamespaceKey)
+	if err != nil {
+		return err
+	}
+
+	manager, err := waddrmgr.Create(waddrmgrNamespace, seed, []byte(pubPass),
+		[]byte(privPass), activeNet.Params, nil)
+	if err != nil {
+		return err
+	}
+
+	manager.Close()
+
+	fmt.Println("The wallet has been created successfully.")
+	return nil
+}