Merge pull request #8983 from LK4D4/consistent_hosts

Consistent hosts
This commit is contained in:
Michael Crosby 2014-11-06 11:51:28 -08:00
commit 85f33388b4
2 changed files with 59 additions and 19 deletions

View file

@ -3,41 +3,55 @@ package etchosts
import (
"bytes"
"fmt"
"io"
"io/ioutil"
"regexp"
)
var defaultContent = map[string]string{
"localhost": "127.0.0.1",
"localhost ip6-localhost ip6-loopback": "::1",
"ip6-localnet": "fe00::0",
"ip6-mcastprefix": "ff00::0",
"ip6-allnodes": "ff02::1",
"ip6-allrouters": "ff02::2",
type Record struct {
Hosts string
IP string
}
func Build(path, IP, hostname, domainname string, extraContent *map[string]string) error {
func (r Record) WriteTo(w io.Writer) (int64, error) {
n, err := fmt.Fprintf(w, "%s\t%s\n", r.IP, r.Hosts)
return int64(n), err
}
var defaultContent = []Record{
{Hosts: "localhost", IP: "127.0.0.1"},
{Hosts: "localhost ip6-localhost ip6-loopback", IP: "::1"},
{Hosts: "ip6-localnet", IP: "fe00::0"},
{Hosts: "ip6-mcastprefix", IP: "ff00::0"},
{Hosts: "ip6-allnodes", IP: "ff02::1"},
{Hosts: "ip6-allrouters", IP: "ff02::2"},
}
func Build(path, IP, hostname, domainname string, extraContent []Record) error {
content := bytes.NewBuffer(nil)
if IP != "" {
var mainRec Record
mainRec.IP = IP
if domainname != "" {
content.WriteString(fmt.Sprintf("%s\t%s.%s %s\n", IP, hostname, domainname, hostname))
mainRec.Hosts = fmt.Sprintf("%s.%s %s", hostname, domainname, hostname)
} else {
content.WriteString(fmt.Sprintf("%s\t%s\n", IP, hostname))
mainRec.Hosts = hostname
}
}
for hosts, ip := range defaultContent {
if _, err := content.WriteString(fmt.Sprintf("%s\t%s\n", ip, hosts)); err != nil {
if _, err := mainRec.WriteTo(content); err != nil {
return err
}
}
if extraContent != nil {
for hosts, ip := range *extraContent {
if _, err := content.WriteString(fmt.Sprintf("%s\t%s\n", ip, hosts)); err != nil {
for _, r := range defaultContent {
if _, err := r.WriteTo(content); err != nil {
return err
}
}
for _, r := range extraContent {
if _, err := r.WriteTo(content); err != nil {
return err
}
}
return ioutil.WriteFile(path, content.Bytes(), 0644)

View file

@ -7,6 +7,32 @@ import (
"testing"
)
func TestBuildDefault(t *testing.T) {
file, err := ioutil.TempFile("", "")
if err != nil {
t.Fatal(err)
}
defer os.Remove(file.Name())
// check that /etc/hosts has consistent ordering
for i := 0; i <= 5; i++ {
err = Build(file.Name(), "", "", "", nil)
if err != nil {
t.Fatal(err)
}
content, err := ioutil.ReadFile(file.Name())
if err != nil {
t.Fatal(err)
}
expected := "127.0.0.1\tlocalhost\n::1\tlocalhost ip6-localhost ip6-loopback\nfe00::0\tip6-localnet\nff00::0\tip6-mcastprefix\nff02::1\tip6-allnodes\nff02::2\tip6-allrouters\n"
if expected != string(content) {
t.Fatalf("Expected to find '%s' got '%s'", expected, content)
}
}
}
func TestBuildHostnameDomainname(t *testing.T) {
file, err := ioutil.TempFile("", "")
if err != nil {