cmd/approve

cmd/approve.go

@@ -8,15 +8,23 @@ import (
 	"github.com/0xPolygonHermez/zkevm-node/config"
 	"github.com/0xPolygonHermez/zkevm-node/encoding"
 	"github.com/0xPolygonHermez/zkevm-node/log"
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/urfave/cli/v2"
 )
 
 func approveTokens(ctx *cli.Context) error {
-	amountArg := ctx.String(config.FlagAmount)
-	amount, _ := new(big.Int).SetString(amountArg, encoding.Base10)
-	if amount == nil {
-		fmt.Println("Please, introduce a valid amount in wei")
-		return nil
+	const bitSize uint = 256
+	useMaxAmountArg := ctx.Bool(config.FlagMaxAmount)
+	var amount *big.Int
+	if !useMaxAmountArg {
+		amountArg := ctx.String(config.FlagAmount)
+		amount, _ = new(big.Int).SetString(amountArg, encoding.Base10)
+		if amount == nil {
+			fmt.Println("Please, introduce a valid amount in wei")
+			return nil
+		}
+	} else {
+		amount = new(big.Int).Sub(new(big.Int).Lsh(common.Big1, bitSize), common.Big1)
 	}
 
 	addrKeyStorePath := ctx.String(config.FlagKeyStorePath)

cmd/main.go

@@ -121,7 +121,13 @@ func main() {
 					Name:     config.FlagAmount,
 					Aliases:  []string{"am"},
 					Usage:    "Amount that is gonna be approved",
-					Required: true,
+					Required: false,
+				},
+				&cli.StringFlag{
+					Name:     config.FlagMaxAmount,
+					Aliases:  []string{"mam"},
+					Usage:    "Maximum amount is gonna be approved",
+					Required: false,
 				},
 				&networkFlag,
 				&customNetworkFlag,

config/config.go

@@ -48,6 +48,8 @@ const (
 	FlagPassword = "password"
 	// FlagMigrations is the flag for migrations.
 	FlagMigrations = "migrations"
+	// FlagMaxAmount is the flag to avoid to use the flag FlagAmount
+	FlagMaxAmount = "max-amount"
 )
 
 // Config represents the configuration of the entire Hermez Node