Golang Extract IP from file (raw.txt)

read-ip-from-file.go

package main

import (
    "fmt"
    "regexp"
    "io/ioutil"
    "log"
)

func main() {
    content, err := ioutil.ReadFile("raw.txt")

     if err != nil {
          log.Fatal(err)
     }

    
    str1 := string(content)

    re := regexp.MustCompile(`(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)(\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){3}`)

    fmt.Printf("Pattern: %v\n", re.String()) // print pattern
    fmt.Println(re.MatchString(str1)) // true

    submatchall := re.FindAllString(str1, -1)
    for _, element := range submatchall {
        fmt.Println(element)
    }
}