update resolver package

dns_resolver/dns_resolver.go

@@ -1,97 +0,0 @@
-// Package dns_resolver is a simple dns resolver
-// based on miekg/dns
-package dns_resolver
-
-import (
-	"errors"
-	"math/rand"
-	"net"
-	"os"
-	"strings"
-	"time"
-
-	"github.com/miekg/dns"
-)
-
-// DnsResolver represents a dns resolver
-type DnsResolver struct {
-	Servers    []string
-	RetryTimes int
-	r          *rand.Rand
-}
-
-// New initializes DnsResolver.
-func New(servers []string) *DnsResolver {
-	for i := range servers {
-		servers[i] = net.JoinHostPort(servers[i], "53")
-	}
-
-	return &DnsResolver{servers, len(servers) * 2, rand.New(rand.NewSource(time.Now().UnixNano()))}
-}
-
-// NewFromResolvConf initializes DnsResolver from resolv.conf like file.
-func NewFromResolvConf(path string) (*DnsResolver, error) {
-	if _, err := os.Stat(path); os.IsNotExist(err) {
-		return &DnsResolver{}, errors.New("no such file or directory: " + path)
-	}
-	config, err := dns.ClientConfigFromFile(path)
-	servers := []string{}
-	for _, ipAddress := range config.Servers {
-		servers = append(servers, net.JoinHostPort(ipAddress, "53"))
-	}
-	return &DnsResolver{servers, len(servers) * 2, rand.New(rand.NewSource(time.Now().UnixNano()))}, err
-}
-
-// LookupHost returns IP addresses of provied host.
-// In case of timeout retries query RetryTimes times.
-func (r *DnsResolver) LookupHost(host string, dnsType uint16) ([]net.IP, error) {
-	return r.lookupHost(host, dnsType, r.RetryTimes)
-}
-
-func (r *DnsResolver) lookupHost(host string, dnsType uint16, triesLeft int) ([]net.IP, error) {
-	m1 := new(dns.Msg)
-	m1.Id = dns.Id()
-	m1.RecursionDesired = true
-	m1.Question = make([]dns.Question, 1)
-
-	switch dnsType {
-	case dns.TypeA:
-		m1.Question[0] = dns.Question{dns.Fqdn(host), dns.TypeA, dns.ClassINET}
-	case dns.TypeAAAA:
-		m1.Question[0] = dns.Question{dns.Fqdn(host), dns.TypeAAAA, dns.ClassINET}
-	}
-
-	in, err := dns.Exchange(m1, r.Servers[r.r.Intn(len(r.Servers))])
-
-	result := []net.IP{}
-
-	if err != nil {
-		if strings.HasSuffix(err.Error(), "i/o timeout") && triesLeft > 0 {
-			triesLeft--
-			return r.lookupHost(host, dnsType, triesLeft)
-		}
-		return result, err
-	}
-
-	if in != nil && in.Rcode != dns.RcodeSuccess {
-		return result, errors.New(dns.RcodeToString[in.Rcode])
-	}
-
-	if dnsType == dns.TypeA {
-		for _, record := range in.Answer {
-			if t, ok := record.(*dns.A); ok {
-				result = append(result, t.A)
-			}
-		}
-	}
-
-	if dnsType == dns.TypeAAAA {
-		for _, record := range in.Answer {
-			if t, ok := record.(*dns.AAAA); ok {
-				result = append(result, t.AAAA)
-			}
-		}
-	}
-
-	return result, err
-}

dns_resolver/dns_resolver_test.go

@@ -1,45 +0,0 @@
-package dns_resolver
-
-import (
-	"fmt"
-	"reflect"
-	"testing"
-
-	"github.com/miekg/dns"
-)
-
-func TestNew(t *testing.T) {
-	servers := []string{"8.8.8.8", "8.8.4.4"}
-	expectedServers := []string{"8.8.8.8:53", "8.8.4.4:53"}
-	resolver := New(servers)
-
-	if !reflect.DeepEqual(resolver.Servers, expectedServers) {
-		t.Error("resolver.Servers: ", resolver.Servers, "should be equal to", expectedServers)
-	}
-}
-
-func TestLookupHost_ValidServer(t *testing.T) {
-	resolver := New([]string{"8.8.8.8", "8.8.4.4"})
-	result, err := resolver.LookupHost("google-public-dns-a.google.com", dns.TypeA)
-	if err != nil {
-		fmt.Println(err.Error())
-		t.Error("Should succeed dns lookup")
-	}
-
-	if result[0].String() != "8.8.8.8" {
-		t.Error("google-public-dns-a.google.com should be resolved to 8.8.8.8")
-	}
-}
-
-func TestLookupHostIPv6_ValidServer(t *testing.T) {
-	resolver := New([]string{"2001:4860:4860::8888", "2001:4860:4860::8844"})
-	result, err := resolver.LookupHost("google-public-dns-a.google.com", dns.TypeAAAA)
-	if err != nil {
-		fmt.Println(err.Error())
-		t.Error("Should succeed dns lookup")
-	}
-
-	if result[0].String() != "2001:4860:4860::8888" {
-		t.Error("result shoudl be: 2001:4860:4860::8888")
-	}
-}

utils.go

@@ -12,7 +12,8 @@ import (
 	"net/http"
 	"strings"
 
-	"github.com/TimothyYe/godns/dns_resolver"
+	dnsResolver "github.com/TimothyYe/godns/resolver"
+
 	"github.com/miekg/dns"
 	"golang.org/x/net/proxy"
 	gomail "gopkg.in/gomail.v2"
@@ -377,7 +378,7 @@ func ResolveDNS(hostname, resolver, ipType string) string {
 		}
 		return dnsAdress[0]
 	}
-	res := dns_resolver.New([]string{resolver})
+	res := dnsResolver.New([]string{resolver})
 	// In case of i/o timeout
 	res.RetryTimes = 5