resolver

README

resolver

⚡ Simply DNS resolver with timeouts

Based on miekg/dns.

Status

Under development

Installation

go get github.com/joy4eg/resolver

Usage

package main

import (
	"fmt"
	"time"

	"github.com/joy4eg/resolver"
)

func main() {
	ip, err := resolver.ResolveIPv4("reddit.com")
	if err != nil {
		panic(err)
	}
	fmt.Println(ip.String()) // 151.101.1.140

	// Or you can use compat API
	ips, err := resolver.LookupIPTimeout("reddit.com", 1 * time.Second)
	if err != nil {
		panic(err)
	}
	fmt.Println(ips) // [151.101.65.140 151.101.1.140 151.101.193.140 151.101.129.140]
}

Author

joy4eg

• http://github.com/joy4eg
• me@ys.lc

License

Released under the MIT License.

Documentation

Index

• Variables
• func LookupAddrTimeout(addr string, timeout time.Duration) (names []string, err error)
• func LookupIPTimeout(host string, timeout time.Duration) (ips []net.IP, err error)
• func ResolveIPVersion(version IPVersion, addr string) (ip net.IP, err error)
• func ResolveIPv4(addr string) (ip net.IP, err error)
• func ResolveIPv6(addr string) (ip net.IP, err error)
• func ResolveIPvALL(addr string) (ips []net.IP, err error)
• func ResolveIPvAUTO(addr string) (ip net.IP, err error)
• func ResolvePTR(ip string) (host string, err error)
• func SetConfig(c Config)
• type Config
• type IPVersion

Variables

var (
	ErrorNoHost           = errors.New("no such host")
	ErrorInvalidIPversion = errors.New("invalid IP version given")
)

var (
	ConfigDefault = Config{
		Servers: []string{
			"208.67.220.220",
			"8.8.4.4",
			"64.6.65.6",
		},
		Timeout:  2 * time.Second,
		Attempts: 2,
	}
)

Default resolver configuration

Functions

func LookupAddrTimeout

func LookupAddrTimeout(addr string, timeout time.Duration) (names []string, err error)

LookupAddr performs a reverse lookup for the given address, returning a list of names mapping to that address.

func LookupIPTimeout

func LookupIPTimeout(host string, timeout time.Duration) (ips []net.IP, err error)

LookupIP looks up host using the configured resolver. It returns an array of that host's IPv4 and IPv6 addresses.

func ResolveIPVersion

func ResolveIPVersion(version IPVersion, addr string) (ip net.IP, err error)

func ResolveIPv4

func ResolveIPv4(addr string) (ip net.IP, err error)

func ResolveIPv6

func ResolveIPv6(addr string) (ip net.IP, err error)

func ResolveIPvALL

func ResolveIPvALL(addr string) (ips []net.IP, err error)

func ResolveIPvAUTO

func ResolveIPvAUTO(addr string) (ip net.IP, err error)

func ResolvePTR

func ResolvePTR(ip string) (host string, err error)

func SetConfig

func SetConfig(c Config)

SetConfig sets the resolver configuration

Types

type Config

type Config struct {
	Servers  []string      // servers to use
	Timeout  time.Duration // a cumulative timeout for dial, write and read, defaults to 2s
	Attempts int           // Total number of resolving attempts
}

Resolver configuration

type IPVersion

type IPVersion string

const (
	IPv4    IPVersion = "ipv4"
	IPv6    IPVersion = "ipv6"
	IPvAUTO IPVersion = "auto"
)