最近在开发一个内部工具，检查服务器上面所有的 dns 设置，我们因为使用了一些自定义的解析，所以需要在服务器 /etc/resolv.conf 里面添加 search 子域名，经过一段时间的研究，发现 docker 项目中 https://github.com/docker/libnetwork 这个库特别适合用来做解析。
使用 "github.com/docker/libnetwork/resolvconf" 这个解析库也是可以的，但是直接引用这个库会存在提示找不到 HashData 这个方法，报错如下:
undefined: ioutils.HashData
原因是 pkg/ioutils 里面没有这个方法，另外 resolvconf\resolvconf.go 文件中引用的都是 github.com/docker/ 的库，如果默认 go get 则会发现很多类型和方法缺失，因为 github.com/docker 这个库在 pkg.go.dev 上面已经很久没有更新了, 目前 https://github.com/moby/libnetwork 上面是最新代码。
工程修改
项目结构
main.go
package main
import (
"ddn_go/pkg/resolvconf"
"fmt"
"io/ioutil"
)
func main() {resolvconfsystem, err := ioutil.ReadFile("/etc/resolv.conf")
if err != nil {fmt.Println(err)
}
fmt.Println("search:", resolvconf.GetSearchDomains(resolvconfsystem))
fmt.Println("server:", resolvconf.GetNameservers(resolvconfsystem, 1))
}
pkg/resolvconf/resolvconf.go
// Package resolvconf provides utility code to query and update DNS configuration in /etc/resolv.conf
package resolvconf
import (
"bytes"
"io/ioutil"
"regexp"
"strings"
"sync"
"ddn_go/pkg/types"
"github.com/docker/libnetwork/resolvconf/dns"
"github.com/sirupsen/logrus"
)
const (// defaultPath is the default path to the resolv.conf that contains information to resolve DNS. See Path().
defaultPath = "/etc/resolv.conf"
// alternatePath is a path different from defaultPath, that may be used to resolve DNS. See Path().
alternatePath = "/run/systemd/resolve/resolv.conf"
)
var (
detectSystemdResolvConfOnce sync.Once
pathAfterSystemdDetection = defaultPath
)
// Path returns the path to the resolv.conf file that libnetwork should use.
//
// When /etc/resolv.conf contains 127.0.0.53 as the only nameserver, then
// it is assumed systemd-resolved manages DNS. Because inside the container 127.0.0.53
// is not a valid DNS server, Path() returns /run/systemd/resolve/resolv.conf
// which is the resolv.conf that systemd-resolved generates and manages.
// Otherwise Path() returns /etc/resolv.conf.
//
// Errors are silenced as they will inevitably resurface at future open/read calls.
//
// More information at https://www.freedesktop.org/software/systemd/man/systemd-resolved.service.html#/etc/resolv.conf
func Path() string {detectSystemdResolvConfOnce.Do(func() {candidateResolvConf, err := ioutil.ReadFile(defaultPath)
if err != nil {
// silencing error as it will resurface at next calls trying to read defaultPath
return
}
ns := GetNameservers(candidateResolvConf, types.IP)
if len(ns) == 1 && ns[0] == "127.0.0.53" {
pathAfterSystemdDetection = alternatePath
logrus.Infof("detected 127.0.0.53 nameserver, assuming systemd-resolved, so using resolv.conf: %s", alternatePath)
}
})
return pathAfterSystemdDetection
}
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})(%\w+)?`
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*$`)
nsIPv6Regexpmatch = regexp.MustCompile(`^\s*nameserver\s*((` + ipv6Address + `))\s*$`)
nsIPv4Regexpmatch = regexp.MustCompile(`^\s*nameserver\s*((` + ipv4Address + `))\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) {return GetSpecific(Path())
}
// 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 := 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(Path())
if err != nil {return nil, err}
newHash, err := 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, types.IP)) == 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 := 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, kind int) []string {nameservers := []string{}
for _, line := range getLines(resolvConf, []byte("#")) {var ns [][]byte
if kind == types.IP {ns = nsRegexp.FindSubmatch(line)
} else if kind == types.IPv4 {ns = nsIPv4Regexpmatch.FindSubmatch(line)
} else if kind == types.IPv6 {ns = nsIPv6Regexpmatch.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, types.IP) {
var address string
// If IPv6, strip zone if present
if strings.Contains(nameserver, ":") {address = strings.Split(nameserver, "%")[0] + "/128"
} else {address = nameserver + "/32"}
nameservers = append(nameservers, address)
}
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 := hashData(bytes.NewReader(content.Bytes()))
if err != nil {return nil, err}
return &File{Content: content.Bytes(), Hash: hash}, ioutil.WriteFile(path, content.Bytes(), 0644)
}pkg/resolvconf/utils.go
package resolvconf
import (
"crypto/sha256"
"encoding/hex"
"io"
)
// hashData returns the sha256 sum of src.
func hashData(src io.Reader) (string, error) {h := sha256.New()
if _, err := io.Copy(h, src); err != nil {return "", err}
return "sha256:" + hex.EncodeToString(h.Sum(nil)), nil
}
pkg/types/types.go
// Package types contains types that are common across libnetwork project
package types
import (
"bytes"
"fmt"
"net"
"strconv"
"strings"
"github.com/ishidawataru/sctp"
)
// constants for the IP address type
const (
IP = iota // IPv4 and IPv6
IPv4
IPv6
)
// EncryptionKey is the libnetwork representation of the key distributed by the lead
// manager.
type EncryptionKey struct {
Subsystem string
Algorithm int32
Key []byte
LamportTime uint64
}
// UUID represents a globally unique ID of various resources like network and endpoint
type UUID string
// QosPolicy represents a quality of service policy on an endpoint
type QosPolicy struct {MaxEgressBandwidth uint64}
// TransportPort represents a local Layer 4 endpoint
type TransportPort struct {
Proto Protocol
Port uint16
}
// Equal checks if this instance of Transportport is equal to the passed one
func (t *TransportPort) Equal(o *TransportPort) bool {
if t == o {return true}
if o == nil {return false}
if t.Proto != o.Proto || t.Port != o.Port {return false}
return true
}
// GetCopy returns a copy of this TransportPort structure instance
func (t *TransportPort) GetCopy() TransportPort {return TransportPort{Proto: t.Proto, Port: t.Port}
}
// String returns the TransportPort structure in string form
func (t *TransportPort) String() string {return fmt.Sprintf("%s/%d", t.Proto.String(), t.Port)
}
// FromString reads the TransportPort structure from string
func (t *TransportPort) FromString(s string) error {ps := strings.Split(s, "/")
if len(ps) == 2 {t.Proto = ParseProtocol(ps[0])
if p, err := strconv.ParseUint(ps[1], 10, 16); err == nil {t.Port = uint16(p)
return nil
}
}
return BadRequestErrorf("invalid format for transport port: %s", s)
}
// PortBinding represents a port binding between the container and the host
type PortBinding struct {
Proto Protocol
IP net.IP
Port uint16
HostIP net.IP
HostPort uint16
HostPortEnd uint16
}
// HostAddr returns the host side transport address
func (p PortBinding) HostAddr() (net.Addr, error) {
switch p.Proto {
case UDP:
return &net.UDPAddr{IP: p.HostIP, Port: int(p.HostPort)}, nil
case TCP:
return &net.TCPAddr{IP: p.HostIP, Port: int(p.HostPort)}, nil
case SCTP:
return &sctp.SCTPAddr{IPAddrs: []net.IPAddr{{IP: p.HostIP}}, Port: int(p.HostPort)}, nil
default:
return nil, ErrInvalidProtocolBinding(p.Proto.String())
}
}
// ContainerAddr returns the container side transport address
func (p PortBinding) ContainerAddr() (net.Addr, error) {
switch p.Proto {
case UDP:
return &net.UDPAddr{IP: p.IP, Port: int(p.Port)}, nil
case TCP:
return &net.TCPAddr{IP: p.IP, Port: int(p.Port)}, nil
case SCTP:
return &sctp.SCTPAddr{IPAddrs: []net.IPAddr{{IP: p.IP}}, Port: int(p.Port)}, nil
default:
return nil, ErrInvalidProtocolBinding(p.Proto.String())
}
}
// GetCopy returns a copy of this PortBinding structure instance
func (p *PortBinding) GetCopy() PortBinding {
return PortBinding{
Proto: p.Proto,
IP: GetIPCopy(p.IP),
Port: p.Port,
HostIP: GetIPCopy(p.HostIP),
HostPort: p.HostPort,
HostPortEnd: p.HostPortEnd,
}
}
// String returns the PortBinding structure in string form
func (p *PortBinding) String() string {ret := fmt.Sprintf("%s/", p.Proto)
if p.IP != nil {ret += p.IP.String()
}
ret = fmt.Sprintf("%s:%d/", ret, p.Port)
if p.HostIP != nil {ret += p.HostIP.String()
}
ret = fmt.Sprintf("%s:%d", ret, p.HostPort)
return ret
}
// FromString reads the PortBinding structure from string s.
// String s is a triple of "protocol/containerIP:port/hostIP:port"
// containerIP and hostIP can be in dotted decimal ("192.0.2.1") or IPv6 ("2001:db8::68") form.
// Zoned addresses ("169.254.0.23%eth0" or "fe80::1ff:fe23:4567:890a%eth0") are not supported.
// If string s is incorrectly formatted or the IP addresses or ports cannot be parsed, FromString
// returns an error.
func (p *PortBinding) FromString(s string) error {ps := strings.Split(s, "/")
if len(ps) != 3 {return BadRequestErrorf("invalid format for port binding: %s", s)
}
p.Proto = ParseProtocol(ps[0])
var err error
if p.IP, p.Port, err = parseIPPort(ps[1]); err != nil {return BadRequestErrorf("failed to parse Container IP/Port in port binding: %s", err.Error())
}
if p.HostIP, p.HostPort, err = parseIPPort(ps[2]); err != nil {return BadRequestErrorf("failed to parse Host IP/Port in port binding: %s", err.Error())
}
return nil
}
func parseIPPort(s string) (net.IP, uint16, error) {hoststr, portstr, err := net.SplitHostPort(s)
if err != nil {return nil, 0, err}
ip := net.ParseIP(hoststr)
if ip == nil {return nil, 0, BadRequestErrorf("invalid ip: %s", hoststr)
}
port, err := strconv.ParseUint(portstr, 10, 16)
if err != nil {return nil, 0, BadRequestErrorf("invalid port: %s", portstr)
}
return ip, uint16(port), nil
}
// Equal checks if this instance of PortBinding is equal to the passed one
func (p *PortBinding) Equal(o *PortBinding) bool {
if p == o {return true}
if o == nil {return false}
if p.Proto != o.Proto || p.Port != o.Port ||
p.HostPort != o.HostPort || p.HostPortEnd != o.HostPortEnd {return false}
if p.IP != nil {if !p.IP.Equal(o.IP) {return false}
} else {
if o.IP != nil {return false}
}
if p.HostIP != nil {if !p.HostIP.Equal(o.HostIP) {return false}
} else {
if o.HostIP != nil {return false}
}
return true
}
// ErrInvalidProtocolBinding is returned when the port binding protocol is not valid.
type ErrInvalidProtocolBinding string
func (ipb ErrInvalidProtocolBinding) Error() string {return fmt.Sprintf("invalid transport protocol: %s", string(ipb))
}
const (
// ICMP is for the ICMP ip protocol
ICMP = 1
// TCP is for the TCP ip protocol
TCP = 6
// UDP is for the UDP ip protocol
UDP = 17
// SCTP is for the SCTP ip protocol
SCTP = 132
)
// Protocol represents an IP protocol number
type Protocol uint8
func (p Protocol) String() string {
switch p {
case ICMP:
return "icmp"
case TCP:
return "tcp"
case UDP:
return "udp"
case SCTP:
return "sctp"
default:
return fmt.Sprintf("%d", p)
}
}
// ParseProtocol returns the respective Protocol type for the passed string
func ParseProtocol(s string) Protocol {switch strings.ToLower(s) {
case "icmp":
return ICMP
case "udp":
return UDP
case "tcp":
return TCP
case "sctp":
return SCTP
default:
return 0
}
}
// GetMacCopy returns a copy of the passed MAC address
func GetMacCopy(from net.HardwareAddr) net.HardwareAddr {
if from == nil {return nil}
to := make(net.HardwareAddr, len(from))
copy(to, from)
return to
}
// GetIPCopy returns a copy of the passed IP address
func GetIPCopy(from net.IP) net.IP {
if from == nil {return nil}
to := make(net.IP, len(from))
copy(to, from)
return to
}
// GetIPNetCopy returns a copy of the passed IP Network
func GetIPNetCopy(from *net.IPNet) *net.IPNet {
if from == nil {return nil}
bm := make(net.IPMask, len(from.Mask))
copy(bm, from.Mask)
return &net.IPNet{IP: GetIPCopy(from.IP), Mask: bm}
}
// GetIPNetCanonical returns the canonical form for the passed network
func GetIPNetCanonical(nw *net.IPNet) *net.IPNet {
if nw == nil {return nil}
c := GetIPNetCopy(nw)
c.IP = c.IP.Mask(nw.Mask)
return c
}
// CompareIPNet returns equal if the two IP Networks are equal
func CompareIPNet(a, b *net.IPNet) bool {
if a == b {return true}
if a == nil || b == nil {return false}
return a.IP.Equal(b.IP) && bytes.Equal(a.Mask, b.Mask)
}
// GetMinimalIP returns the address in its shortest form
// If ip contains an IPv4-mapped IPv6 address, the 4-octet form of the IPv4 address will be returned.
// Otherwise ip is returned unchanged.
func GetMinimalIP(ip net.IP) net.IP {if ip != nil && ip.To4() != nil {return ip.To4()
}
return ip
}
// GetMinimalIPNet returns a copy of the passed IP Network with congruent ip and mask notation
func GetMinimalIPNet(nw *net.IPNet) *net.IPNet {
if nw == nil {return nil}
if len(nw.IP) == 16 && nw.IP.To4() != nil {
m := nw.Mask
if len(m) == 16 {m = m[12:16]
}
return &net.IPNet{IP: nw.IP.To4(), Mask: m}
}
return nw
}
// IsIPNetValid returns true if the ipnet is a valid network/mask
// combination. Otherwise returns false.
func IsIPNetValid(nw *net.IPNet) bool {return nw.String() != "0.0.0.0/0"
}
var v4inV6MaskPrefix = []byte{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}
// compareIPMask checks if the passed ip and mask are semantically compatible.
// It returns the byte indexes for the address and mask so that caller can
// do bitwise operations without modifying address representation.
func compareIPMask(ip net.IP, mask net.IPMask) (is int, ms int, err error) {
// Find the effective starting of address and mask
if len(ip) == net.IPv6len && ip.To4() != nil {is = 12}
if len(ip[is:]) == net.IPv4len && len(mask) == net.IPv6len && bytes.Equal(mask[:12], v4inV6MaskPrefix) {ms = 12}
// Check if address and mask are semantically compatible
if len(ip[is:]) != len(mask[ms:]) {err = fmt.Errorf("ip and mask are not compatible: (%#v, %#v)", ip, mask)
}
return
}
// GetHostPartIP returns the host portion of the ip address identified by the mask.
// IP address representation is not modified. If address and mask are not compatible
// an error is returned.
func GetHostPartIP(ip net.IP, mask net.IPMask) (net.IP, error) {
// Find the effective starting of address and mask
is, ms, err := compareIPMask(ip, mask)
if err != nil {return nil, fmt.Errorf("cannot compute host portion ip address because %s", err)
}
// Compute host portion
out := GetIPCopy(ip)
for i := 0; i < len(mask[ms:]); i++ {out[is+i] &= ^mask[ms+i]
}
return out, nil
}
// GetBroadcastIP returns the broadcast ip address for the passed network (ip and mask).
// IP address representation is not modified. If address and mask are not compatible
// an error is returned.
func GetBroadcastIP(ip net.IP, mask net.IPMask) (net.IP, error) {
// Find the effective starting of address and mask
is, ms, err := compareIPMask(ip, mask)
if err != nil {return nil, fmt.Errorf("cannot compute broadcast ip address because %s", err)
}
// Compute broadcast address
out := GetIPCopy(ip)
for i := 0; i < len(mask[ms:]); i++ {out[is+i] |= ^mask[ms+i]
}
return out, nil
}
// ParseCIDR returns the *net.IPNet represented by the passed CIDR notation
func ParseCIDR(cidr string) (n *net.IPNet, e error) {
var i net.IP
if i, n, e = net.ParseCIDR(cidr); e == nil {n.IP = i}
return
}
const (
// NEXTHOP indicates a StaticRoute with an IP next hop.
NEXTHOP = iota
// CONNECTED indicates a StaticRoute with an interface for directly connected peers.
CONNECTED
)
// StaticRoute is a statically-provisioned IP route.
type StaticRoute struct {
Destination *net.IPNet
RouteType int // NEXT_HOP or CONNECTED
// NextHop will be resolved by the kernel (i.e. as a loose hop).
NextHop net.IP
}
// GetCopy returns a copy of this StaticRoute structure
func (r *StaticRoute) GetCopy() *StaticRoute {d := GetIPNetCopy(r.Destination)
nh := GetIPCopy(r.NextHop)
return &StaticRoute{Destination: d,
RouteType: r.RouteType,
NextHop: nh,
}
}
// InterfaceStatistics represents the interface's statistics
type InterfaceStatistics struct {
RxBytes uint64
RxPackets uint64
RxErrors uint64
RxDropped uint64
TxBytes uint64
TxPackets uint64
TxErrors uint64
TxDropped uint64
}
func (is *InterfaceStatistics) String() string {
return fmt.Sprintf("\nRxBytes: %d, RxPackets: %d, RxErrors: %d, RxDropped: %d, TxBytes: %d, TxPackets: %d, TxErrors: %d, TxDropped: %d",
is.RxBytes, is.RxPackets, is.RxErrors, is.RxDropped, is.TxBytes, is.TxPackets, is.TxErrors, is.TxDropped)
}
/******************************
* Well-known Error Interfaces
******************************/
// MaskableError is an interface for errors which can be ignored by caller
type MaskableError interface {
// Maskable makes implementer into MaskableError type
Maskable()}
// RetryError is an interface for errors which might get resolved through retry
type RetryError interface {
// Retry makes implementer into RetryError type
Retry()}
// BadRequestError is an interface for errors originated by a bad request
type BadRequestError interface {
// BadRequest makes implementer into BadRequestError type
BadRequest()}
// NotFoundError is an interface for errors raised because a needed resource is not available
type NotFoundError interface {
// NotFound makes implementer into NotFoundError type
NotFound()}
// ForbiddenError is an interface for errors which denote a valid request that cannot be honored
type ForbiddenError interface {
// Forbidden makes implementer into ForbiddenError type
Forbidden()}
// NoServiceError is an interface for errors returned when the required service is not available
type NoServiceError interface {
// NoService makes implementer into NoServiceError type
NoService()}
// TimeoutError is an interface for errors raised because of timeout
type TimeoutError interface {
// Timeout makes implementer into TimeoutError type
Timeout()}
// NotImplementedError is an interface for errors raised because of requested functionality is not yet implemented
type NotImplementedError interface {
// NotImplemented makes implementer into NotImplementedError type
NotImplemented()}
// InternalError is an interface for errors raised because of an internal error
type InternalError interface {
// Internal makes implementer into InternalError type
Internal()}
/******************************
* Well-known Error Formatters
******************************/
// BadRequestErrorf creates an instance of BadRequestError
func BadRequestErrorf(format string, params ...interface{}) error {return badRequest(fmt.Sprintf(format, params...))
}
// NotFoundErrorf creates an instance of NotFoundError
func NotFoundErrorf(format string, params ...interface{}) error {return notFound(fmt.Sprintf(format, params...))
}
// ForbiddenErrorf creates an instance of ForbiddenError
func ForbiddenErrorf(format string, params ...interface{}) error {return forbidden(fmt.Sprintf(format, params...))
}
// NoServiceErrorf creates an instance of NoServiceError
func NoServiceErrorf(format string, params ...interface{}) error {return noService(fmt.Sprintf(format, params...))
}
// NotImplementedErrorf creates an instance of NotImplementedError
func NotImplementedErrorf(format string, params ...interface{}) error {return notImpl(fmt.Sprintf(format, params...))
}
// TimeoutErrorf creates an instance of TimeoutError
func TimeoutErrorf(format string, params ...interface{}) error {return timeout(fmt.Sprintf(format, params...))
}
// InternalErrorf creates an instance of InternalError
func InternalErrorf(format string, params ...interface{}) error {return internal(fmt.Sprintf(format, params...))
}
// InternalMaskableErrorf creates an instance of InternalError and MaskableError
func InternalMaskableErrorf(format string, params ...interface{}) error {return maskInternal(fmt.Sprintf(format, params...))
}
// RetryErrorf creates an instance of RetryError
func RetryErrorf(format string, params ...interface{}) error {return retry(fmt.Sprintf(format, params...))
}
/***********************
* Internal Error Types
***********************/
type badRequest string
func (br badRequest) Error() string {return string(br)
}
func (br badRequest) BadRequest() {}
type notFound string
func (nf notFound) Error() string {return string(nf)
}
func (nf notFound) NotFound() {}
type forbidden string
func (frb forbidden) Error() string {return string(frb)
}
func (frb forbidden) Forbidden() {}
type noService string
func (ns noService) Error() string {return string(ns)
}
func (ns noService) NoService() {}
type timeout string
func (to timeout) Error() string {return string(to)
}
func (to timeout) Timeout() {}
type notImpl string
func (ni notImpl) Error() string {return string(ni)
}
func (ni notImpl) NotImplemented() {}
type internal string
func (nt internal) Error() string {return string(nt)
}
func (nt internal) Internal() {}
type maskInternal string
func (mnt maskInternal) Error() string {return string(mnt)
}
func (mnt maskInternal) Internal() {}
func (mnt maskInternal) Maskable() {}
type retry string
func (r retry) Error() string {return string(r)
}
func (r retry) Retry() {}
项目没有直接引入整个 docker 网络包，提取了 dns 解析部分，自定义了 hashData 方法，引入官方 type 文件
最后完美运行，解析成功
