Reduce code complexity of testnet command

server/testnet.go

@@ -60,10 +60,11 @@ Example:
 }
 
 func testnetWithConfig(config *cfg.Config, cdc *wire.Codec, appInit AppInit) error {
-
 	outDir := viper.GetString(outputDir)
+	numValidators := viper.GetInt(nValidators)
+
 	// Generate private key, node ID, initial transaction
-	for i := 0; i < viper.GetInt(nValidators); i++ {
+	for i := 0; i < numValidators; i++ {
 		nodeDirName := fmt.Sprintf("%s%d", viper.GetString(nodeDirPrefix), i)
 		nodeDir := filepath.Join(outDir, nodeDirName, "gaiad")
 		clientDir := filepath.Join(outDir, nodeDirName, "gaiacli")
@@ -83,18 +84,9 @@ func testnetWithConfig(config *cfg.Config, cdc *wire.Codec, appInit AppInit) err
 		}
 
 		config.Moniker = nodeDirName
-
+		ip, err := getIP(i)
-		ip := viper.GetString(startingIPAddress)
+		if err != nil {
-		if len(ip) == 0 {
+			return err
-			ip, err = externalIP()
-			if err != nil {
-				return err
-			}
-		} else {
-			ip, err = calculateIP(ip, i)
-			if err != nil {
-				return err
-			}
 		}
 
 		genTxConfig := gc.GenTx{
@@ -112,35 +104,22 @@ func testnetWithConfig(config *cfg.Config, cdc *wire.Codec, appInit AppInit) err
 
 		// Save private key seed words
 		name := fmt.Sprintf("%v.json", "key_seed")
-		writePath := filepath.Join(clientDir)
+		err = writeFile(name, clientDir, cliPrint)
-		file := filepath.Join(writePath, name)
-		err = cmn.EnsureDir(writePath, 0700)
-		if err != nil {
-			return err
-		}
-		err = cmn.WriteFile(file, cliPrint, 0600)
 		if err != nil {
 			return err
 		}
 
 		// Gather gentxs folder
 		name = fmt.Sprintf("%v.json", nodeDirName)
-		writePath = filepath.Join(gentxsDir)
+		err = writeFile(name, gentxsDir, genTxFile)
-		file = filepath.Join(writePath, name)
-		err = cmn.EnsureDir(writePath, 0700)
 		if err != nil {
 			return err
 		}
-		err = cmn.WriteFile(file, genTxFile, 0644)
-		if err != nil {
-			return err
-		}
-
 	}
 
 	// Generate genesis.json and config.toml
 	chainID := "chain-" + cmn.RandStr(6)
-	for i := 0; i < viper.GetInt(nValidators); i++ {
+	for i := 0; i < numValidators; i++ {
 
 		nodeDirName := fmt.Sprintf("%s%d", viper.GetString(nodeDirPrefix), i)
 		nodeDir := filepath.Join(outDir, nodeDirName, "gaiad")
@@ -165,6 +144,36 @@ func testnetWithConfig(config *cfg.Config, cdc *wire.Codec, appInit AppInit) err
 	return nil
 }
 
+func getIP(i int) (ip string, err error) {
+	ip = viper.GetString(startingIPAddress)
+	if len(ip) == 0 {
+		ip, err = externalIP()
+		if err != nil {
+			return "", err
+		}
+	} else {
+		ip, err = calculateIP(ip, i)
+		if err != nil {
+			return "", err
+		}
+	}
+	return ip, nil
+}
+
+func writeFile(name string, dir string, contents []byte) error {
+	writePath := filepath.Join(dir)
+	file := filepath.Join(writePath, name)
+	err := cmn.EnsureDir(writePath, 0700)
+	if err != nil {
+		return err
+	}
+	err = cmn.WriteFile(file, contents, 0600)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
 func calculateIP(ip string, i int) (string, error) {
 	ipv4 := net.ParseIP(ip).To4()
 	if ipv4 == nil {