Example of using https://github.com/fiorix/freegeoip geoip database in golang

readme.md

Usage

You can specify a file location, or just let it download one for you.

A) Local database:

wget http://geolite.maxmind.com/download/geoip/database/GeoLite2-City.mmdb.gz

Then just load it

// Load IP database
err = IPDB.Load("db.gz")
if err != nil {
	logger.Fatal(err)
}
defer IPDB.Close()

B) Auto-updating remote database: link

// Load IP database
err = IPDB.Load("")
if err != nil {
	logger.Fatal(err)
}
defer IPDB.Close()

Usage

var s freegeoip.DefaultQuery
theStruct, err := IPDB.Lookup("8.8.8.8")
if err != nil {
	log.Println(err)
	continue
}
fmt.Println(theStruct)

ipdb.go

package main

import (
	"net"
	"time"

	"github.com/fiorix/freegeoip"
)

// IPDatabase Wrapper Struct
type IPDatabase struct {
	DB *freegeoip.DB
}

// Load the Database
func (i *IPDatabase) Load(location string) (err error) {

	if len(location) != 0 {
		i.DB, err = freegeoip.Open(location)
		if err != nil {
			return
		}
	} else {
		updateInterval := 24 * time.Hour
		maxRetryInterval := time.Hour
		i.DB, err = freegeoip.OpenURL(freegeoip.MaxMindDB, updateInterval, maxRetryInterval)
		if err != nil {
			return
		}
	}

	select {
	case <-i.DB.NotifyOpen():
		// Wait for the db to be downloaded.
	case err = <-i.DB.NotifyError():
		return
	}
	return
}

// Close the database connection
func (i *IPDatabase) Close() {
	i.DB.Close()
}

// Lookup an IP in the database
func (i *IPDatabase) Lookup(ipAddress string) (result freegeoip.DefaultQuery, err error) {
	err = i.DB.Lookup(net.ParseIP(ipAddress), &result)
	return
}