touchup

cmd/geth/config.go

@@ -20,6 +20,7 @@ import (
 	"bufio"
 	"errors"
 	"fmt"
+	"github.com/ethereum/go-ethereum/crypto"
 	"os"
 	"reflect"
 	"runtime"
@@ -239,6 +240,31 @@ func makeFullNode(ctx *cli.Context) *node.Node {
 		}
 		catalyst.RegisterSimulatedBeaconAPIs(stack, simBeacon)
 		stack.RegisterLifecycle(simBeacon)
+
+		devModeBanner := `You are running Geth in development mode.  Please note the following:
+    1. Unless --dev.period is specified, the client will mine blocks as soon as there 
+       are transactions in the pool.  It will mine as fast as possible until the pool is empty.
+    2. Networking is disabled.`
+		// if we are running in ephemeral dev mode and a keystore is not set,
+		// the default developer address will be prefunded.  Let the user know
+		// about this account and its corresponding private key.
+		if !ctx.IsSet(utils.DataDirFlag.Name) && cfg.Eth.Miner.PendingFeeRecipient == utils.DeveloperAddr {
+			devModeBanner += fmt.Sprintf(`
+    3. --datadir has not been specified. The chain will be kept in memory and not persisted 
+       after client shutdown.  The following account has been prefunded in the Genesis:
+
+       Account
+       ------------------
+       0x%x (10^49 ETH)
+
+       Private Key
+       ------------------
+       0x%x
+`, utils.DeveloperAddr, crypto.FromECDSA(utils.DeveloperKey))
+		}
+		for _, line := range strings.Split(devModeBanner, "\n") {
+			log.Warn(line)
+		}
 	} else if ctx.IsSet(utils.BeaconApiFlag.Name) {
 		// Start blsync mode.
 		srv := rpc.NewServer()

cmd/utils/flags.go

@@ -984,6 +984,12 @@ var (
 	}
 )
 
+// default account to prefund when running Geth in ephemeral development mode
+var (
+	DeveloperKey, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
+	DeveloperAddr   = crypto.PubkeyToAddress(DeveloperKey.PublicKey)
+)
+
 // MakeDataDir retrieves the currently requested data directory, terminating
 // if none (or the empty string) is specified. If the node is starting a testnet,
 // then a subdirectory of the specified datadir will be used.
@@ -1769,7 +1775,7 @@ func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *ethconfig.Config) {
 		} else if accs := ks.Accounts(); len(accs) > 0 {
 			developer = ks.Accounts()[0]
 		} else {
-			developer, err = ks.NewAccount(passphrase)
+			developer, err = ks.ImportECDSA(DeveloperKey, passphrase)
 			if err != nil {
 				Fatalf("Failed to create developer account: %v", err)
 			}
@@ -1808,30 +1814,7 @@ func SetEthConfig(ctx *cli.Context, stack *node.Node, cfg *ethconfig.Config) {
 			chaindb.Close()
 		} else {
 			// if no datadir is specified, dev mode runs ephemerally in memory
-			var (
+			cfg.Genesis = core.DeveloperGenesisBlock(ctx.Uint64(DeveloperGasLimitFlag.Name), &developer.Address)
-				devAddr = developer.Address
-				devKey  *ecdsa.PrivateKey
-			)
-			if devAddr != (common.Address{}) {
-				devKey, err = crypto.GenerateKey()
-				if err != nil {
-					panic(fmt.Errorf("failed to generate dev mode prefunded account key: %v", err))
-				}
-				devAddr = crypto.PubkeyToAddress(devKey.PublicKey)
-
-				devModeAccountsDescr := fmt.Sprintf(`Available Accounts\n
-==================
-(0) 0x%x (10000.000000000000000000 ETH)
-
-Private Keys
-==================
-(0) 0x%x (10000.000000000000000000 ETH)
-`, devAddr, crypto.FromECDSA(devKey))
-				for _, line := range strings.Split(devModeAccountsDescr, "\n") {
-					log.Info(line)
-				}
-			}
-			cfg.Genesis = core.DeveloperGenesisBlock(ctx.Uint64(DeveloperGasLimitFlag.Name), &devAddr)
 		}
 		if !ctx.IsSet(MinerGasPriceFlag.Name) {
 			cfg.Miner.GasPrice = big.NewInt(1)