VMware vSphere Integrated Containers provider (#206)

* Add Virtual Kubelet provider for VIC

Initial virtual kubelet provider for VMware VIC.  This provider currently
handles creating and starting of a pod VM via the VIC portlayer and persona
server.  Image store handling via the VIC persona server.  This provider
currently requires the feature/wolfpack branch of VIC.

* Added pod stop and delete.  Also added node capacity.

Added the ability to stop and delete pod VMs via VIC.  Also retrieve
node capacity information from the VCH.

* Cleanup and readme file

Some file clean up and added a Readme.md markdown file for the VIC
provider.

* Cleaned up errors, added function comments, moved operation code

1. Cleaned up error handling.  Set standard for creating errors.
2. Added method prototype comments for all interface functions.
3. Moved PodCreator, PodStarter, PodStopper, and PodDeleter to a new folder.

* Add mocking code and unit tests for podcache, podcreator, and podstarter

Used the unit test framework used in VIC to handle assertions in the provider's
unit test.  Mocking code generated using OSS project mockery, which is compatible
with the testify assertion framework.

* Vendored packages for the VIC provider

Requires feature/wolfpack branch of VIC and a few specific commit sha of
projects used within VIC.

* Implementation of POD Stopper and Deleter unit tests (#4)

* Updated files for initial PR

vendor/github.com/docker/libnetwork/resolvconf/README.md

@@ -0,0 +1 @@
+Package resolvconf provides utility code to query and update DNS configuration in /etc/resolv.conf

vendor/github.com/docker/libnetwork/resolvconf/dns/resolvconf.go

@@ -0,0 +1,17 @@
+package dns
+
+import (
+	"regexp"
+)
+
+// IPLocalhost is a regex patter for localhost IP address range.
+const IPLocalhost = `((127\.([0-9]{1,3}\.){2}[0-9]{1,3})|(::1)$)`
+
+var localhostIPRegexp = regexp.MustCompile(IPLocalhost)
+
+// IsLocalhost returns true if ip matches the localhost IP regular expression.
+// Used for determining if nameserver settings are being passed which are
+// localhost addresses
+func IsLocalhost(ip string) bool {
+	return localhostIPRegexp.MatchString(ip)
+}

vendor/github.com/docker/libnetwork/resolvconf/resolvconf.go

@@ -0,0 +1,237 @@
+// Package resolvconf provides utility code to query and update DNS configuration in /etc/resolv.conf
+package resolvconf
+
+import (
+	"bytes"
+	"io/ioutil"
+	"regexp"
+	"strings"
+	"sync"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/docker/docker/pkg/ioutils"
+	"github.com/docker/libnetwork/resolvconf/dns"
+)
+
+var (
+	// Note: the default IPv4 & IPv6 resolvers are set to Google's Public DNS
+	defaultIPv4Dns = []string{"nameserver 8.8.8.8", "nameserver 8.8.4.4"}
+	defaultIPv6Dns = []string{"nameserver 2001:4860:4860::8888", "nameserver 2001:4860:4860::8844"}
+	ipv4NumBlock   = `(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)`
+	ipv4Address    = `(` + ipv4NumBlock + `\.){3}` + ipv4NumBlock
+	// This is not an IPv6 address verifier as it will accept a super-set of IPv6, and also
+	// will *not match* IPv4-Embedded IPv6 Addresses (RFC6052), but that and other variants
+	// -- e.g. other link-local types -- either won't work in containers or are unnecessary.
+	// For readability and sufficiency for Docker purposes this seemed more reasonable than a
+	// 1000+ character regexp with exact and complete IPv6 validation
+	ipv6Address = `([0-9A-Fa-f]{0,4}:){2,7}([0-9A-Fa-f]{0,4})`
+
+	localhostNSRegexp = regexp.MustCompile(`(?m)^nameserver\s+` + dns.IPLocalhost + `\s*\n*`)
+	nsIPv6Regexp      = regexp.MustCompile(`(?m)^nameserver\s+` + ipv6Address + `\s*\n*`)
+	nsRegexp          = regexp.MustCompile(`^\s*nameserver\s*((` + ipv4Address + `)|(` + ipv6Address + `))\s*$`)
+	searchRegexp      = regexp.MustCompile(`^\s*search\s*(([^\s]+\s*)*)$`)
+	optionsRegexp     = regexp.MustCompile(`^\s*options\s*(([^\s]+\s*)*)$`)
+)
+
+var lastModified struct {
+	sync.Mutex
+	sha256   string
+	contents []byte
+}
+
+// File contains the resolv.conf content and its hash
+type File struct {
+	Content []byte
+	Hash    string
+}
+
+// Get returns the contents of /etc/resolv.conf and its hash
+func Get() (*File, error) {
+	resolv, err := ioutil.ReadFile("/etc/resolv.conf")
+	if err != nil {
+		return nil, err
+	}
+	hash, err := ioutils.HashData(bytes.NewReader(resolv))
+	if err != nil {
+		return nil, err
+	}
+	return &File{Content: resolv, Hash: hash}, nil
+}
+
+// GetSpecific returns the contents of the user specified resolv.conf file and its hash
+func GetSpecific(path string) (*File, error) {
+	resolv, err := ioutil.ReadFile(path)
+	if err != nil {
+		return nil, err
+	}
+	hash, err := ioutils.HashData(bytes.NewReader(resolv))
+	if err != nil {
+		return nil, err
+	}
+	return &File{Content: resolv, Hash: hash}, nil
+}
+
+// GetIfChanged retrieves the host /etc/resolv.conf file, checks against the last hash
+// and, if modified since last check, returns the bytes and new hash.
+// This feature is used by the resolv.conf updater for containers
+func GetIfChanged() (*File, error) {
+	lastModified.Lock()
+	defer lastModified.Unlock()
+
+	resolv, err := ioutil.ReadFile("/etc/resolv.conf")
+	if err != nil {
+		return nil, err
+	}
+	newHash, err := ioutils.HashData(bytes.NewReader(resolv))
+	if err != nil {
+		return nil, err
+	}
+	if lastModified.sha256 != newHash {
+		lastModified.sha256 = newHash
+		lastModified.contents = resolv
+		return &File{Content: resolv, Hash: newHash}, nil
+	}
+	// nothing changed, so return no data
+	return nil, nil
+}
+
+// GetLastModified retrieves the last used contents and hash of the host resolv.conf.
+// Used by containers updating on restart
+func GetLastModified() *File {
+	lastModified.Lock()
+	defer lastModified.Unlock()
+
+	return &File{Content: lastModified.contents, Hash: lastModified.sha256}
+}
+
+// FilterResolvDNS cleans up the config in resolvConf.  It has two main jobs:
+// 1. It looks for localhost (127.*|::1) entries in the provided
+//    resolv.conf, removing local nameserver entries, and, if the resulting
+//    cleaned config has no defined nameservers left, adds default DNS entries
+// 2. Given the caller provides the enable/disable state of IPv6, the filter
+//    code will remove all IPv6 nameservers if it is not enabled for containers
+//
+func FilterResolvDNS(resolvConf []byte, ipv6Enabled bool) (*File, error) {
+	cleanedResolvConf := localhostNSRegexp.ReplaceAll(resolvConf, []byte{})
+	// if IPv6 is not enabled, also clean out any IPv6 address nameserver
+	if !ipv6Enabled {
+		cleanedResolvConf = nsIPv6Regexp.ReplaceAll(cleanedResolvConf, []byte{})
+	}
+	// if the resulting resolvConf has no more nameservers defined, add appropriate
+	// default DNS servers for IPv4 and (optionally) IPv6
+	if len(GetNameservers(cleanedResolvConf)) == 0 {
+		logrus.Infof("No non-localhost DNS nameservers are left in resolv.conf. Using default external servers : %v", defaultIPv4Dns)
+		dns := defaultIPv4Dns
+		if ipv6Enabled {
+			logrus.Infof("IPv6 enabled; Adding default IPv6 external servers : %v", defaultIPv6Dns)
+			dns = append(dns, defaultIPv6Dns...)
+		}
+		cleanedResolvConf = append(cleanedResolvConf, []byte("\n"+strings.Join(dns, "\n"))...)
+	}
+	hash, err := ioutils.HashData(bytes.NewReader(cleanedResolvConf))
+	if err != nil {
+		return nil, err
+	}
+	return &File{Content: cleanedResolvConf, Hash: hash}, nil
+}
+
+// getLines parses input into lines and strips away comments.
+func getLines(input []byte, commentMarker []byte) [][]byte {
+	lines := bytes.Split(input, []byte("\n"))
+	var output [][]byte
+	for _, currentLine := range lines {
+		var commentIndex = bytes.Index(currentLine, commentMarker)
+		if commentIndex == -1 {
+			output = append(output, currentLine)
+		} else {
+			output = append(output, currentLine[:commentIndex])
+		}
+	}
+	return output
+}
+
+// GetNameservers returns nameservers (if any) listed in /etc/resolv.conf
+func GetNameservers(resolvConf []byte) []string {
+	nameservers := []string{}
+	for _, line := range getLines(resolvConf, []byte("#")) {
+		var ns = nsRegexp.FindSubmatch(line)
+		if len(ns) > 0 {
+			nameservers = append(nameservers, string(ns[1]))
+		}
+	}
+	return nameservers
+}
+
+// GetNameserversAsCIDR returns nameservers (if any) listed in
+// /etc/resolv.conf as CIDR blocks (e.g., "1.2.3.4/32")
+// This function's output is intended for net.ParseCIDR
+func GetNameserversAsCIDR(resolvConf []byte) []string {
+	nameservers := []string{}
+	for _, nameserver := range GetNameservers(resolvConf) {
+		nameservers = append(nameservers, nameserver+"/32")
+	}
+	return nameservers
+}
+
+// GetSearchDomains returns search domains (if any) listed in /etc/resolv.conf
+// If more than one search line is encountered, only the contents of the last
+// one is returned.
+func GetSearchDomains(resolvConf []byte) []string {
+	domains := []string{}
+	for _, line := range getLines(resolvConf, []byte("#")) {
+		match := searchRegexp.FindSubmatch(line)
+		if match == nil {
+			continue
+		}
+		domains = strings.Fields(string(match[1]))
+	}
+	return domains
+}
+
+// GetOptions returns options (if any) listed in /etc/resolv.conf
+// If more than one options line is encountered, only the contents of the last
+// one is returned.
+func GetOptions(resolvConf []byte) []string {
+	options := []string{}
+	for _, line := range getLines(resolvConf, []byte("#")) {
+		match := optionsRegexp.FindSubmatch(line)
+		if match == nil {
+			continue
+		}
+		options = strings.Fields(string(match[1]))
+	}
+	return options
+}
+
+// Build writes a configuration file to path containing a "nameserver" entry
+// for every element in dns, a "search" entry for every element in
+// dnsSearch, and an "options" entry for every element in dnsOptions.
+func Build(path string, dns, dnsSearch, dnsOptions []string) (*File, error) {
+	content := bytes.NewBuffer(nil)
+	if len(dnsSearch) > 0 {
+		if searchString := strings.Join(dnsSearch, " "); strings.Trim(searchString, " ") != "." {
+			if _, err := content.WriteString("search " + searchString + "\n"); err != nil {
+				return nil, err
+			}
+		}
+	}
+	for _, dns := range dns {
+		if _, err := content.WriteString("nameserver " + dns + "\n"); err != nil {
+			return nil, err
+		}
+	}
+	if len(dnsOptions) > 0 {
+		if optsString := strings.Join(dnsOptions, " "); strings.Trim(optsString, " ") != "" {
+			if _, err := content.WriteString("options " + optsString + "\n"); err != nil {
+				return nil, err
+			}
+		}
+	}
+
+	hash, err := ioutils.HashData(bytes.NewReader(content.Bytes()))
+	if err != nil {
+		return nil, err
+	}
+
+	return &File{Content: content.Bytes(), Hash: hash}, ioutil.WriteFile(path, content.Bytes(), 0644)
+}

vendor/github.com/docker/libnetwork/resolvconf/resolvconf_test.go

@@ -0,0 +1,299 @@
+package resolvconf
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"testing"
+
+	"github.com/docker/docker/pkg/ioutils"
+	_ "github.com/docker/libnetwork/testutils"
+)
+
+func TestGet(t *testing.T) {
+	resolvConfUtils, err := Get()
+	if err != nil {
+		t.Fatal(err)
+	}
+	resolvConfSystem, err := ioutil.ReadFile("/etc/resolv.conf")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if string(resolvConfUtils.Content) != string(resolvConfSystem) {
+		t.Fatalf("/etc/resolv.conf and GetResolvConf have different content.")
+	}
+	hashSystem, err := ioutils.HashData(bytes.NewReader(resolvConfSystem))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if resolvConfUtils.Hash != hashSystem {
+		t.Fatalf("/etc/resolv.conf and GetResolvConf have different hashes.")
+	}
+}
+
+func TestGetNameservers(t *testing.T) {
+	for resolv, result := range map[string][]string{`
+nameserver 1.2.3.4
+nameserver 40.3.200.10
+search example.com`: {"1.2.3.4", "40.3.200.10"},
+		`search example.com`: {},
+		`nameserver 1.2.3.4
+search example.com
+nameserver 4.30.20.100`: {"1.2.3.4", "4.30.20.100"},
+		``: {},
+		`  nameserver 1.2.3.4   `: {"1.2.3.4"},
+		`search example.com
+nameserver 1.2.3.4
+#nameserver 4.3.2.1`: {"1.2.3.4"},
+		`search example.com
+nameserver 1.2.3.4 # not 4.3.2.1`: {"1.2.3.4"},
+	} {
+		test := GetNameservers([]byte(resolv))
+		if !strSlicesEqual(test, result) {
+			t.Fatalf("Wrong nameserver string {%s} should be %v. Input: %s", test, result, resolv)
+		}
+	}
+}
+
+func TestGetNameserversAsCIDR(t *testing.T) {
+	for resolv, result := range map[string][]string{`
+nameserver 1.2.3.4
+nameserver 40.3.200.10
+search example.com`: {"1.2.3.4/32", "40.3.200.10/32"},
+		`search example.com`: {},
+		`nameserver 1.2.3.4
+search example.com
+nameserver 4.30.20.100`: {"1.2.3.4/32", "4.30.20.100/32"},
+		``: {},
+		`  nameserver 1.2.3.4   `: {"1.2.3.4/32"},
+		`search example.com
+nameserver 1.2.3.4
+#nameserver 4.3.2.1`: {"1.2.3.4/32"},
+		`search example.com
+nameserver 1.2.3.4 # not 4.3.2.1`: {"1.2.3.4/32"},
+	} {
+		test := GetNameserversAsCIDR([]byte(resolv))
+		if !strSlicesEqual(test, result) {
+			t.Fatalf("Wrong nameserver string {%s} should be %v. Input: %s", test, result, resolv)
+		}
+	}
+}
+
+func TestGetSearchDomains(t *testing.T) {
+	for resolv, result := range map[string][]string{
+		`search example.com`:           {"example.com"},
+		`search example.com # ignored`: {"example.com"},
+		` 	  search 	 example.com 	  `: {"example.com"},
+		` 	  search 	 example.com 	  # ignored`: {"example.com"},
+		`search foo.example.com example.com`: {"foo.example.com", "example.com"},
+		`	   search   	   foo.example.com 	 example.com 	`: {"foo.example.com", "example.com"},
+		`	   search   	   foo.example.com 	 example.com 	# ignored`: {"foo.example.com", "example.com"},
+		``:          {},
+		`# ignored`: {},
+		`nameserver 1.2.3.4
+search foo.example.com example.com`: {"foo.example.com", "example.com"},
+		`nameserver 1.2.3.4
+search dup1.example.com dup2.example.com
+search foo.example.com example.com`: {"foo.example.com", "example.com"},
+		`nameserver 1.2.3.4
+search foo.example.com example.com
+nameserver 4.30.20.100`: {"foo.example.com", "example.com"},
+	} {
+		test := GetSearchDomains([]byte(resolv))
+		if !strSlicesEqual(test, result) {
+			t.Fatalf("Wrong search domain string {%s} should be %v. Input: %s", test, result, resolv)
+		}
+	}
+}
+
+func TestGetOptions(t *testing.T) {
+	for resolv, result := range map[string][]string{
+		`options opt1`:           {"opt1"},
+		`options opt1 # ignored`: {"opt1"},
+		` 	  options 	 opt1 	  `: {"opt1"},
+		` 	  options 	 opt1 	  # ignored`: {"opt1"},
+		`options opt1 opt2 opt3`:           {"opt1", "opt2", "opt3"},
+		`options opt1 opt2 opt3 # ignored`: {"opt1", "opt2", "opt3"},
+		`	   options 	 opt1 	 opt2 	 opt3 	`: {"opt1", "opt2", "opt3"},
+		`	   options 	 opt1 	 opt2 	 opt3 	# ignored`: {"opt1", "opt2", "opt3"},
+		``:                   {},
+		`# ignored`:          {},
+		`nameserver 1.2.3.4`: {},
+		`nameserver 1.2.3.4
+options opt1 opt2 opt3`: {"opt1", "opt2", "opt3"},
+		`nameserver 1.2.3.4
+options opt1 opt2
+options opt3 opt4`: {"opt3", "opt4"},
+	} {
+		test := GetOptions([]byte(resolv))
+		if !strSlicesEqual(test, result) {
+			t.Fatalf("Wrong options string {%s} should be %v. Input: %s", test, result, resolv)
+		}
+	}
+}
+
+func strSlicesEqual(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+
+	for i, v := range a {
+		if v != b[i] {
+			return false
+		}
+	}
+
+	return true
+}
+
+func TestBuild(t *testing.T) {
+	file, err := ioutil.TempFile("", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(file.Name())
+
+	_, err = Build(file.Name(), []string{"ns1", "ns2", "ns3"}, []string{"search1"}, []string{"opt1"})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	content, err := ioutil.ReadFile(file.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if expected := "search search1\nnameserver ns1\nnameserver ns2\nnameserver ns3\noptions opt1\n"; !bytes.Contains(content, []byte(expected)) {
+		t.Fatalf("Expected to find '%s' got '%s'", expected, content)
+	}
+}
+
+func TestBuildWithZeroLengthDomainSearch(t *testing.T) {
+	file, err := ioutil.TempFile("", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(file.Name())
+
+	_, err = Build(file.Name(), []string{"ns1", "ns2", "ns3"}, []string{"."}, []string{"opt1"})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	content, err := ioutil.ReadFile(file.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if expected := "nameserver ns1\nnameserver ns2\nnameserver ns3\noptions opt1\n"; !bytes.Contains(content, []byte(expected)) {
+		t.Fatalf("Expected to find '%s' got '%s'", expected, content)
+	}
+	if notExpected := "search ."; bytes.Contains(content, []byte(notExpected)) {
+		t.Fatalf("Expected to not find '%s' got '%s'", notExpected, content)
+	}
+}
+
+func TestBuildWithNoOptions(t *testing.T) {
+	file, err := ioutil.TempFile("", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(file.Name())
+
+	_, err = Build(file.Name(), []string{"ns1", "ns2", "ns3"}, []string{"search1"}, []string{})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	content, err := ioutil.ReadFile(file.Name())
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if expected := "search search1\nnameserver ns1\nnameserver ns2\nnameserver ns3\n"; !bytes.Contains(content, []byte(expected)) {
+		t.Fatalf("Expected to find '%s' got '%s'", expected, content)
+	}
+	if notExpected := "search ."; bytes.Contains(content, []byte(notExpected)) {
+		t.Fatalf("Expected to not find '%s' got '%s'", notExpected, content)
+	}
+}
+
+func TestFilterResolvDns(t *testing.T) {
+	ns0 := "nameserver 10.16.60.14\nnameserver 10.16.60.21\n"
+
+	if result, _ := FilterResolvDNS([]byte(ns0), false); result != nil {
+		if ns0 != string(result.Content) {
+			t.Fatalf("Failed No Localhost: expected \n<%s> got \n<%s>", ns0, string(result.Content))
+		}
+	}
+
+	ns1 := "nameserver 10.16.60.14\nnameserver 10.16.60.21\nnameserver 127.0.0.1\n"
+	if result, _ := FilterResolvDNS([]byte(ns1), false); result != nil {
+		if ns0 != string(result.Content) {
+			t.Fatalf("Failed Localhost: expected \n<%s> got \n<%s>", ns0, string(result.Content))
+		}
+	}
+
+	ns1 = "nameserver 10.16.60.14\nnameserver 127.0.0.1\nnameserver 10.16.60.21\n"
+	if result, _ := FilterResolvDNS([]byte(ns1), false); result != nil {
+		if ns0 != string(result.Content) {
+			t.Fatalf("Failed Localhost: expected \n<%s> got \n<%s>", ns0, string(result.Content))
+		}
+	}
+
+	ns1 = "nameserver 127.0.1.1\nnameserver 10.16.60.14\nnameserver 10.16.60.21\n"
+	if result, _ := FilterResolvDNS([]byte(ns1), false); result != nil {
+		if ns0 != string(result.Content) {
+			t.Fatalf("Failed Localhost: expected \n<%s> got \n<%s>", ns0, string(result.Content))
+		}
+	}
+
+	ns1 = "nameserver ::1\nnameserver 10.16.60.14\nnameserver 127.0.2.1\nnameserver 10.16.60.21\n"
+	if result, _ := FilterResolvDNS([]byte(ns1), false); result != nil {
+		if ns0 != string(result.Content) {
+			t.Fatalf("Failed Localhost: expected \n<%s> got \n<%s>", ns0, string(result.Content))
+		}
+	}
+
+	ns1 = "nameserver 10.16.60.14\nnameserver ::1\nnameserver 10.16.60.21\nnameserver ::1"
+	if result, _ := FilterResolvDNS([]byte(ns1), false); result != nil {
+		if ns0 != string(result.Content) {
+			t.Fatalf("Failed Localhost: expected \n<%s> got \n<%s>", ns0, string(result.Content))
+		}
+	}
+
+	// with IPv6 disabled (false param), the IPv6 nameserver should be removed
+	ns1 = "nameserver 10.16.60.14\nnameserver 2002:dead:beef::1\nnameserver 10.16.60.21\nnameserver ::1"
+	if result, _ := FilterResolvDNS([]byte(ns1), false); result != nil {
+		if ns0 != string(result.Content) {
+			t.Fatalf("Failed Localhost+IPv6 off: expected \n<%s> got \n<%s>", ns0, string(result.Content))
+		}
+	}
+
+	// with IPv6 enabled, the IPv6 nameserver should be preserved
+	ns0 = "nameserver 10.16.60.14\nnameserver 2002:dead:beef::1\nnameserver 10.16.60.21\n"
+	ns1 = "nameserver 10.16.60.14\nnameserver 2002:dead:beef::1\nnameserver 10.16.60.21\nnameserver ::1"
+	if result, _ := FilterResolvDNS([]byte(ns1), true); result != nil {
+		if ns0 != string(result.Content) {
+			t.Fatalf("Failed Localhost+IPv6 on: expected \n<%s> got \n<%s>", ns0, string(result.Content))
+		}
+	}
+
+	// with IPv6 enabled, and no non-localhost servers, Google defaults (both IPv4+IPv6) should be added
+	ns0 = "\nnameserver 8.8.8.8\nnameserver 8.8.4.4\nnameserver 2001:4860:4860::8888\nnameserver 2001:4860:4860::8844"
+	ns1 = "nameserver 127.0.0.1\nnameserver ::1\nnameserver 127.0.2.1"
+	if result, _ := FilterResolvDNS([]byte(ns1), true); result != nil {
+		if ns0 != string(result.Content) {
+			t.Fatalf("Failed no Localhost+IPv6 enabled: expected \n<%s> got \n<%s>", ns0, string(result.Content))
+		}
+	}
+
+	// with IPv6 disabled, and no non-localhost servers, Google defaults (only IPv4) should be added
+	ns0 = "\nnameserver 8.8.8.8\nnameserver 8.8.4.4"
+	ns1 = "nameserver 127.0.0.1\nnameserver ::1\nnameserver 127.0.2.1"
+	if result, _ := FilterResolvDNS([]byte(ns1), false); result != nil {
+		if ns0 != string(result.Content) {
+			t.Fatalf("Failed no Localhost+IPv6 enabled: expected \n<%s> got \n<%s>", ns0, string(result.Content))
+		}
+	}
+}