Capture IPs from heroku log drain

rails_logs.go

package main

import (
  "fmt"
  "os"
  "bufio"
  "regexp"
)

var IP_REGEX = regexp.MustCompile(`([\d]{1,3}\.[\d]{1,3}\.[\d]{1,3}\.[\d]{1,3})`)

func print_ip(str string) {
  match := IP_REGEX.FindString(str)

  if len(match) > 0 {
    fmt.Println(match)
  }
}

func main() {
  reader := bufio.NewReader(os.Stdin)

  for {
    str, err := reader.ReadString('\n')
    
    if err != nil {
      fmt.Println("ERROR:", err)
      break
    }

    print_ip(str)
  }
}