Check if an IP address is IPV4 or IPV6 in Go (Golang)

• IPV4 address is of 4 bytes string with each byte separated by dot (‘.’)

• IPV6 address is 8 groups of 4 hexagonal digits separated by colon (‘:’)

The below code

• Prints invalid if the given IP address is invalid
• Else it prints whether the IP address is ipV4 or ipV6

Code:

package main

import (
    "fmt"
    "net"
)

func main() {
    validIPV4 := "10.40.210.253"
    checkIPAddressType(validIPV4)
    
    invalidIPV4 := "1000.40.210.253"
    checkIPAddressType(invalidIPV4)
    
    valiIPV6 := "2001:0db8:85a3:0000:0000:8a2e:0370:7334"
    checkIPAddressType(valiIPV6)
    
    invalidIPV6 := "2001:0db8:85a3:0000:0000:8a2e:0370:7334:3445"
    checkIPAddressType(invalidIPV6)
}

func checkIPAddressType(ip string) {
    if net.ParseIP(ip) == nil {
        fmt.Printf("Invalid IP Address: %s\n", ip)
        return
    }
    for i := 0; i < len(ip); i++ {
        switch ip[i] {
        case '.':
            fmt.Printf("Given IP Address %s is IPV4 type\n", ip)
            return
        case ':':
            fmt.Printf("Given IP Address %s is IPV6 type\n", ip)
            return
        }
    }
}

Output:

Given IP Address 10.40.210.253 is IPV4 type
Invalid IP Address: 1000.40.210.253
Given IP Address 2001:0db8:85a3:0000:0000:8a2e:0370:7334 is IPV6 type
Invalid IP Address: 2001:0db8:85a3:0000:0000:8a2e:0370:7334:3445