plugeth-utils/restricted/types.go
2021-09-16 15:52:50 -05:00

56 lines
1.3 KiB
Go

package restricted
import (
"fmt"
"math"
"github.com/openrelayxyz/plugeth-utils/restricted/hexutil"
"strings"
)
type BlockNumber int64
const (
PendingBlockNumber = BlockNumber(-2)
LatestBlockNumber = BlockNumber(-1)
EarliestBlockNumber = BlockNumber(0)
)
// UnmarshalJSON parses the given JSON fragment into a BlockNumber. It supports:
// - "latest", "earliest" or "pending" as string arguments
// - the block number
// Returned errors:
// - an invalid block number error when the given argument isn't a known strings
// - an out of range error when the given block number is either too little or too large
func (bn *BlockNumber) UnmarshalJSON(data []byte) error {
input := strings.TrimSpace(string(data))
if len(input) >= 2 && input[0] == '"' && input[len(input)-1] == '"' {
input = input[1 : len(input)-1]
}
switch input {
case "earliest":
*bn = EarliestBlockNumber
return nil
case "latest":
*bn = LatestBlockNumber
return nil
case "pending":
*bn = PendingBlockNumber
return nil
}
blckNum, err := hexutil.DecodeUint64(input)
if err != nil {
return err
}
if blckNum > math.MaxInt64 {
return fmt.Errorf("block number larger than int64")
}
*bn = BlockNumber(blckNum)
return nil
}
func (bn BlockNumber) Int64() int64 {
return (int64)(bn)
}