echoip/cmd/echoip/main.go

package main

import (
	"log"

	flags "github.com/jessevdk/go-flags"

	"os"

	"github.com/mpolden/echoip/http"
	"github.com/mpolden/echoip/iputil"
	"github.com/mpolden/echoip/iputil/geo"
)

func main() {
	var opts struct {
		CountryDBPath string   `short:"f" long:"country-db" description:"Path to GeoIP country database" value-name:"FILE" default:""`
		CityDBPath    string   `short:"c" long:"city-db" description:"Path to GeoIP city database" value-name:"FILE" default:""`
		ASNDBPath     string   `short:"a" long:"asn-db" description:"Path to GeoIP ASN database" value-name:"FILE" default:""`
		Listen        string   `short:"l" long:"listen" description:"Listening address" value-name:"ADDR" default:":8080"`
		ReverseLookup bool     `short:"r" long:"reverse-lookup" description:"Perform reverse hostname lookups"`
		PortLookup    bool     `short:"p" long:"port-lookup" description:"Enable port lookup"`
		Template      string   `short:"t" long:"template" description:"Path to template" default:"index.html" value-name:"FILE"`
		IPHeaders     []string `short:"H" long:"trusted-header" description:"Header to trust for remote IP, if present (e.g. X-Real-IP)" value-name:"NAME"`
		CacheCapacity int      `short:"C" long:"cache-size" description:"Size of response cache. Set to 0 to disable" value-name:"SIZE"`
	}
	_, err := flags.ParseArgs(&opts, os.Args)
	if err != nil {
		os.Exit(1)
	}

	log := log.New(os.Stderr, "echoip: ", 0)
	r, err := geo.Open(opts.CountryDBPath, opts.CityDBPath, opts.ASNDBPath)
	if err != nil {
		log.Fatal(err)
	}
	cache := http.NewCache(opts.CacheCapacity)
	server := http.New(r, cache)
	server.IPHeaders = opts.IPHeaders
	if _, err := os.Stat(opts.Template); err == nil {
		server.Template = opts.Template
	} else {
		log.Printf("Not configuring default handler: Template not found: %s", opts.Template)
	}
	if opts.ReverseLookup {
		log.Println("Enabling reverse lookup")
		server.LookupAddr = iputil.LookupAddr
	}
	if opts.PortLookup {
		log.Println("Enabling port lookup")
		server.LookupPort = iputil.LookupPort
	}
	if len(opts.IPHeaders) > 0 {
		log.Printf("Trusting header(s) %+v to contain correct remote IP", opts.IPHeaders)
	}

	listen := opts.Listen
	if listen == ":8080" {
		listen = "0.0.0.0:8080"
	}
	log.Printf("Listening on http://%s", listen)
	if err := server.ListenAndServe(opts.Listen); err != nil {
		log.Fatal(err)
	}
}