How to validate an etherum address (go)?

Question

I'm looping through various addresses and I need to know which ones are BTC addresses and which are ETH addresses. So far I just check if the address is hex encoded. Is this function safe to use?

package main

import (
    "encoding/hex"
    "strings"
    "fmt"
)

func main() {
    key := "1DfjCuWDKRWpv1vGP9UNsb4ooArWnXfqnr"
    fmt.Println(isEther(key)) 
}

func isEther(s string) bool {
    s = strings.TrimPrefix(s, "0x")
    _, err := hex.DecodeString(s)
    if err == nil {
        return true
    }
    return false
}

Answer 1

From types.go:

// IsHexAddress verifies whether a string can represent a valid hex-encoded
// Ethereum address or not.
func IsHexAddress(s string) bool {
    if hasHexPrefix(s) {
        s = s[2:]
    }
    return len(s) == 2*AddressLength && isHex(s)
}

You'll need to pull in the other called functions and variables, or redefine them in your own file.

There are other address-related utility functions in that file that might also be of use.

Answer 2

You can also use a regular expression to check if an Ethereum address is valid:

package main

import (
    "fmt"
    "regexp"
)

func IsValidAddress(v string) bool {
    re := regexp.MustCompile("^0x[0-9a-fA-F]{40}$")
    return re.MatchString(v)
}

func main() {
    fmt.Println(IsValidAddress("0x323b5d4c32345ced77393b3530b1eed0f346429d")) // true
    fmt.Println(IsValidAddress("0xXYZb5d4c32345ced77393b3530b1eed0f346429d")) // false
}

https://play.golang.org/p/k3JqUnZBiKK