adding etcd client dependencies

This commit is contained in:
Vicki Cheung 2015-11-16 13:30:27 -08:00
parent dfe284af43
commit dc4374ab79
13 changed files with 916 additions and 0 deletions

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!pkg/

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// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package pathutil
import "path"
// CanonicalURLPath returns the canonical url path for p, which follows the rules:
// 1. the path always starts with "/"
// 2. replace multiple slashes with a single slash
// 3. replace each '.' '..' path name element with equivalent one
// 4. keep the trailing slash
// The function is borrowed from stdlib http.cleanPath in server.go.
func CanonicalURLPath(p string) string {
if p == "" {
return "/"
}
if p[0] != '/' {
p = "/" + p
}
np := path.Clean(p)
// path.Clean removes trailing slash except for root,
// put the trailing slash back if necessary.
if p[len(p)-1] == '/' && np != "/" {
np += "/"
}
return np
}

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package transport
import (
"crypto/tls"
"fmt"
"net"
"time"
)
// NewKeepAliveListener returns a listener that listens on the given address.
// http://tldp.org/HOWTO/TCP-Keepalive-HOWTO/overview.html
func NewKeepAliveListener(addr string, scheme string, info TLSInfo) (net.Listener, error) {
l, err := net.Listen("tcp", addr)
if err != nil {
return nil, err
}
if scheme == "https" {
if info.Empty() {
return nil, fmt.Errorf("cannot listen on TLS for %s: KeyFile and CertFile are not presented", scheme+"://"+addr)
}
cfg, err := info.ServerConfig()
if err != nil {
return nil, err
}
return newTLSKeepaliveListener(l, cfg), nil
}
return &keepaliveListener{
Listener: l,
}, nil
}
type keepaliveListener struct{ net.Listener }
func (kln *keepaliveListener) Accept() (net.Conn, error) {
c, err := kln.Listener.Accept()
if err != nil {
return nil, err
}
tcpc := c.(*net.TCPConn)
// detection time: tcp_keepalive_time + tcp_keepalive_probes + tcp_keepalive_intvl
// default on linux: 30 + 8 * 30
// default on osx: 30 + 8 * 75
tcpc.SetKeepAlive(true)
tcpc.SetKeepAlivePeriod(30 * time.Second)
return tcpc, nil
}
// A tlsKeepaliveListener implements a network listener (net.Listener) for TLS connections.
type tlsKeepaliveListener struct {
net.Listener
config *tls.Config
}
// Accept waits for and returns the next incoming TLS connection.
// The returned connection c is a *tls.Conn.
func (l *tlsKeepaliveListener) Accept() (c net.Conn, err error) {
c, err = l.Listener.Accept()
if err != nil {
return
}
tcpc := c.(*net.TCPConn)
// detection time: tcp_keepalive_time + tcp_keepalive_probes + tcp_keepalive_intvl
// default on linux: 30 + 8 * 30
// default on osx: 30 + 8 * 75
tcpc.SetKeepAlive(true)
tcpc.SetKeepAlivePeriod(30 * time.Second)
c = tls.Server(c, l.config)
return
}
// NewListener creates a Listener which accepts connections from an inner
// Listener and wraps each connection with Server.
// The configuration config must be non-nil and must have
// at least one certificate.
func newTLSKeepaliveListener(inner net.Listener, config *tls.Config) net.Listener {
l := &tlsKeepaliveListener{}
l.Listener = inner
l.config = config
return l
}

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package transport
import (
"crypto/tls"
"crypto/x509"
"encoding/pem"
"fmt"
"io/ioutil"
"net"
"net/http"
"time"
)
func NewListener(addr string, scheme string, info TLSInfo) (net.Listener, error) {
l, err := net.Listen("tcp", addr)
if err != nil {
return nil, err
}
if scheme == "https" {
if info.Empty() {
return nil, fmt.Errorf("cannot listen on TLS for %s: KeyFile and CertFile are not presented", scheme+"://"+addr)
}
cfg, err := info.ServerConfig()
if err != nil {
return nil, err
}
l = tls.NewListener(l, cfg)
}
return l, nil
}
func NewTransport(info TLSInfo, dialtimeoutd time.Duration) (*http.Transport, error) {
cfg, err := info.ClientConfig()
if err != nil {
return nil, err
}
t := &http.Transport{
Dial: (&net.Dialer{
Timeout: dialtimeoutd,
// value taken from http.DefaultTransport
KeepAlive: 30 * time.Second,
}).Dial,
// value taken from http.DefaultTransport
TLSHandshakeTimeout: 10 * time.Second,
TLSClientConfig: cfg,
}
return t, nil
}
type TLSInfo struct {
CertFile string
KeyFile string
CAFile string
TrustedCAFile string
ClientCertAuth bool
// parseFunc exists to simplify testing. Typically, parseFunc
// should be left nil. In that case, tls.X509KeyPair will be used.
parseFunc func([]byte, []byte) (tls.Certificate, error)
}
func (info TLSInfo) String() string {
return fmt.Sprintf("cert = %s, key = %s, ca = %s, trusted-ca = %s, client-cert-auth = %v", info.CertFile, info.KeyFile, info.CAFile, info.TrustedCAFile, info.ClientCertAuth)
}
func (info TLSInfo) Empty() bool {
return info.CertFile == "" && info.KeyFile == ""
}
func (info TLSInfo) baseConfig() (*tls.Config, error) {
if info.KeyFile == "" || info.CertFile == "" {
return nil, fmt.Errorf("KeyFile and CertFile must both be present[key: %v, cert: %v]", info.KeyFile, info.CertFile)
}
cert, err := ioutil.ReadFile(info.CertFile)
if err != nil {
return nil, err
}
key, err := ioutil.ReadFile(info.KeyFile)
if err != nil {
return nil, err
}
parseFunc := info.parseFunc
if parseFunc == nil {
parseFunc = tls.X509KeyPair
}
tlsCert, err := parseFunc(cert, key)
if err != nil {
return nil, err
}
cfg := &tls.Config{
Certificates: []tls.Certificate{tlsCert},
MinVersion: tls.VersionTLS10,
}
return cfg, nil
}
// cafiles returns a list of CA file paths.
func (info TLSInfo) cafiles() []string {
cs := make([]string, 0)
if info.CAFile != "" {
cs = append(cs, info.CAFile)
}
if info.TrustedCAFile != "" {
cs = append(cs, info.TrustedCAFile)
}
return cs
}
// ServerConfig generates a tls.Config object for use by an HTTP server.
func (info TLSInfo) ServerConfig() (*tls.Config, error) {
cfg, err := info.baseConfig()
if err != nil {
return nil, err
}
cfg.ClientAuth = tls.NoClientCert
if info.CAFile != "" || info.ClientCertAuth {
cfg.ClientAuth = tls.RequireAndVerifyClientCert
}
CAFiles := info.cafiles()
if len(CAFiles) > 0 {
cp, err := newCertPool(CAFiles)
if err != nil {
return nil, err
}
cfg.ClientCAs = cp
}
return cfg, nil
}
// ClientConfig generates a tls.Config object for use by an HTTP client.
func (info TLSInfo) ClientConfig() (*tls.Config, error) {
var cfg *tls.Config
var err error
if !info.Empty() {
cfg, err = info.baseConfig()
if err != nil {
return nil, err
}
} else {
cfg = &tls.Config{}
}
CAFiles := info.cafiles()
if len(CAFiles) > 0 {
cfg.RootCAs, err = newCertPool(CAFiles)
if err != nil {
return nil, err
}
}
return cfg, nil
}
// newCertPool creates x509 certPool with provided CA files.
func newCertPool(CAFiles []string) (*x509.CertPool, error) {
certPool := x509.NewCertPool()
for _, CAFile := range CAFiles {
pemByte, err := ioutil.ReadFile(CAFile)
if err != nil {
return nil, err
}
for {
var block *pem.Block
block, pemByte = pem.Decode(pemByte)
if block == nil {
break
}
cert, err := x509.ParseCertificate(block.Bytes)
if err != nil {
return nil, err
}
certPool.AddCert(cert)
}
}
return certPool, nil
}

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package transport
import (
"net"
"time"
)
type timeoutConn struct {
net.Conn
wtimeoutd time.Duration
rdtimeoutd time.Duration
}
func (c timeoutConn) Write(b []byte) (n int, err error) {
if c.wtimeoutd > 0 {
if err := c.SetWriteDeadline(time.Now().Add(c.wtimeoutd)); err != nil {
return 0, err
}
}
return c.Conn.Write(b)
}
func (c timeoutConn) Read(b []byte) (n int, err error) {
if c.rdtimeoutd > 0 {
if err := c.SetReadDeadline(time.Now().Add(c.rdtimeoutd)); err != nil {
return 0, err
}
}
return c.Conn.Read(b)
}

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package transport
import (
"net"
"time"
)
type rwTimeoutDialer struct {
wtimeoutd time.Duration
rdtimeoutd time.Duration
net.Dialer
}
func (d *rwTimeoutDialer) Dial(network, address string) (net.Conn, error) {
conn, err := d.Dialer.Dial(network, address)
tconn := &timeoutConn{
rdtimeoutd: d.rdtimeoutd,
wtimeoutd: d.wtimeoutd,
Conn: conn,
}
return tconn, err
}

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package transport
import (
"net"
"time"
)
// NewTimeoutListener returns a listener that listens on the given address.
// If read/write on the accepted connection blocks longer than its time limit,
// it will return timeout error.
func NewTimeoutListener(addr string, scheme string, info TLSInfo, rdtimeoutd, wtimeoutd time.Duration) (net.Listener, error) {
ln, err := NewListener(addr, scheme, info)
if err != nil {
return nil, err
}
return &rwTimeoutListener{
Listener: ln,
rdtimeoutd: rdtimeoutd,
wtimeoutd: wtimeoutd,
}, nil
}
type rwTimeoutListener struct {
net.Listener
wtimeoutd time.Duration
rdtimeoutd time.Duration
}
func (rwln *rwTimeoutListener) Accept() (net.Conn, error) {
c, err := rwln.Listener.Accept()
if err != nil {
return nil, err
}
return timeoutConn{
Conn: c,
wtimeoutd: rwln.wtimeoutd,
rdtimeoutd: rwln.rdtimeoutd,
}, nil
}

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package transport
import (
"net"
"net/http"
"time"
)
// NewTimeoutTransport returns a transport created using the given TLS info.
// If read/write on the created connection blocks longer than its time limit,
// it will return timeout error.
func NewTimeoutTransport(info TLSInfo, dialtimeoutd, rdtimeoutd, wtimeoutd time.Duration) (*http.Transport, error) {
tr, err := NewTransport(info, dialtimeoutd)
if err != nil {
return nil, err
}
// the timeouted connection will tiemout soon after it is idle.
// it should not be put back to http transport as an idle connection for future usage.
tr.MaxIdleConnsPerHost = -1
tr.Dial = (&rwTimeoutDialer{
Dialer: net.Dialer{
Timeout: dialtimeoutd,
KeepAlive: 30 * time.Second,
},
rdtimeoutd: rdtimeoutd,
wtimeoutd: wtimeoutd,
}).Dial
return tr, nil
}

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package types
import (
"strconv"
)
// ID represents a generic identifier which is canonically
// stored as a uint64 but is typically represented as a
// base-16 string for input/output
type ID uint64
func (i ID) String() string {
return strconv.FormatUint(uint64(i), 16)
}
// IDFromString attempts to create an ID from a base-16 string.
func IDFromString(s string) (ID, error) {
i, err := strconv.ParseUint(s, 16, 64)
return ID(i), err
}
// IDSlice implements the sort interface
type IDSlice []ID
func (p IDSlice) Len() int { return len(p) }
func (p IDSlice) Less(i, j int) bool { return uint64(p[i]) < uint64(p[j]) }
func (p IDSlice) Swap(i, j int) { p[i], p[j] = p[j], p[i] }

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package types
import (
"reflect"
"sort"
"sync"
)
type Set interface {
Add(string)
Remove(string)
Contains(string) bool
Equals(Set) bool
Length() int
Values() []string
Copy() Set
Sub(Set) Set
}
func NewUnsafeSet(values ...string) *unsafeSet {
set := &unsafeSet{make(map[string]struct{})}
for _, v := range values {
set.Add(v)
}
return set
}
func NewThreadsafeSet(values ...string) *tsafeSet {
us := NewUnsafeSet(values...)
return &tsafeSet{us, sync.RWMutex{}}
}
type unsafeSet struct {
d map[string]struct{}
}
// Add adds a new value to the set (no-op if the value is already present)
func (us *unsafeSet) Add(value string) {
us.d[value] = struct{}{}
}
// Remove removes the given value from the set
func (us *unsafeSet) Remove(value string) {
delete(us.d, value)
}
// Contains returns whether the set contains the given value
func (us *unsafeSet) Contains(value string) (exists bool) {
_, exists = us.d[value]
return
}
// ContainsAll returns whether the set contains all given values
func (us *unsafeSet) ContainsAll(values []string) bool {
for _, s := range values {
if !us.Contains(s) {
return false
}
}
return true
}
// Equals returns whether the contents of two sets are identical
func (us *unsafeSet) Equals(other Set) bool {
v1 := sort.StringSlice(us.Values())
v2 := sort.StringSlice(other.Values())
v1.Sort()
v2.Sort()
return reflect.DeepEqual(v1, v2)
}
// Length returns the number of elements in the set
func (us *unsafeSet) Length() int {
return len(us.d)
}
// Values returns the values of the Set in an unspecified order.
func (us *unsafeSet) Values() (values []string) {
values = make([]string, 0)
for val := range us.d {
values = append(values, val)
}
return
}
// Copy creates a new Set containing the values of the first
func (us *unsafeSet) Copy() Set {
cp := NewUnsafeSet()
for val := range us.d {
cp.Add(val)
}
return cp
}
// Sub removes all elements in other from the set
func (us *unsafeSet) Sub(other Set) Set {
oValues := other.Values()
result := us.Copy().(*unsafeSet)
for _, val := range oValues {
if _, ok := result.d[val]; !ok {
continue
}
delete(result.d, val)
}
return result
}
type tsafeSet struct {
us *unsafeSet
m sync.RWMutex
}
func (ts *tsafeSet) Add(value string) {
ts.m.Lock()
defer ts.m.Unlock()
ts.us.Add(value)
}
func (ts *tsafeSet) Remove(value string) {
ts.m.Lock()
defer ts.m.Unlock()
ts.us.Remove(value)
}
func (ts *tsafeSet) Contains(value string) (exists bool) {
ts.m.RLock()
defer ts.m.RUnlock()
return ts.us.Contains(value)
}
func (ts *tsafeSet) Equals(other Set) bool {
ts.m.RLock()
defer ts.m.RUnlock()
return ts.us.Equals(other)
}
func (ts *tsafeSet) Length() int {
ts.m.RLock()
defer ts.m.RUnlock()
return ts.us.Length()
}
func (ts *tsafeSet) Values() (values []string) {
ts.m.RLock()
defer ts.m.RUnlock()
return ts.us.Values()
}
func (ts *tsafeSet) Copy() Set {
ts.m.RLock()
defer ts.m.RUnlock()
usResult := ts.us.Copy().(*unsafeSet)
return &tsafeSet{usResult, sync.RWMutex{}}
}
func (ts *tsafeSet) Sub(other Set) Set {
ts.m.RLock()
defer ts.m.RUnlock()
usResult := ts.us.Sub(other).(*unsafeSet)
return &tsafeSet{usResult, sync.RWMutex{}}
}

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package types
// Uint64Slice implements sort interface
type Uint64Slice []uint64
func (p Uint64Slice) Len() int { return len(p) }
func (p Uint64Slice) Less(i, j int) bool { return p[i] < p[j] }
func (p Uint64Slice) Swap(i, j int) { p[i], p[j] = p[j], p[i] }

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package types
import (
"errors"
"fmt"
"net"
"net/url"
"sort"
"strings"
)
type URLs []url.URL
func NewURLs(strs []string) (URLs, error) {
all := make([]url.URL, len(strs))
if len(all) == 0 {
return nil, errors.New("no valid URLs given")
}
for i, in := range strs {
in = strings.TrimSpace(in)
u, err := url.Parse(in)
if err != nil {
return nil, err
}
if u.Scheme != "http" && u.Scheme != "https" {
return nil, fmt.Errorf("URL scheme must be http or https: %s", in)
}
if _, _, err := net.SplitHostPort(u.Host); err != nil {
return nil, fmt.Errorf(`URL address does not have the form "host:port": %s`, in)
}
if u.Path != "" {
return nil, fmt.Errorf("URL must not contain a path: %s", in)
}
all[i] = *u
}
us := URLs(all)
us.Sort()
return us, nil
}
func (us URLs) String() string {
return strings.Join(us.StringSlice(), ",")
}
func (us *URLs) Sort() {
sort.Sort(us)
}
func (us URLs) Len() int { return len(us) }
func (us URLs) Less(i, j int) bool { return us[i].String() < us[j].String() }
func (us URLs) Swap(i, j int) { us[i], us[j] = us[j], us[i] }
func (us URLs) StringSlice() []string {
out := make([]string, len(us))
for i := range us {
out[i] = us[i].String()
}
return out
}

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// Copyright 2015 CoreOS, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package types
import (
"fmt"
"sort"
"strings"
)
type URLsMap map[string]URLs
// NewURLsMap returns a URLsMap instantiated from the given string,
// which consists of discovery-formatted names-to-URLs, like:
// mach0=http://1.1.1.1:2380,mach0=http://2.2.2.2::2380,mach1=http://3.3.3.3:2380,mach2=http://4.4.4.4:2380
func NewURLsMap(s string) (URLsMap, error) {
m := parse(s)
cl := URLsMap{}
for name, urls := range m {
us, err := NewURLs(urls)
if err != nil {
return nil, err
}
cl[name] = us
}
return cl, nil
}
// String returns NameURLPairs into discovery-formatted name-to-URLs sorted by name.
func (c URLsMap) String() string {
pairs := make([]string, 0)
for name, urls := range c {
for _, url := range urls {
pairs = append(pairs, fmt.Sprintf("%s=%s", name, url.String()))
}
}
sort.Strings(pairs)
return strings.Join(pairs, ",")
}
// URLs returns a list of all URLs.
// The returned list is sorted in ascending lexicographical order.
func (c URLsMap) URLs() []string {
urls := make([]string, 0)
for _, us := range c {
for _, u := range us {
urls = append(urls, u.String())
}
}
sort.Strings(urls)
return urls
}
func (c URLsMap) Len() int {
return len(c)
}
// parse parses the given string and returns a map listing the values specified for each key.
func parse(s string) map[string][]string {
m := make(map[string][]string)
for s != "" {
key := s
if i := strings.IndexAny(key, ","); i >= 0 {
key, s = key[:i], key[i+1:]
} else {
s = ""
}
if key == "" {
continue
}
value := ""
if i := strings.Index(key, "="); i >= 0 {
key, value = key[:i], key[i+1:]
}
m[key] = append(m[key], value)
}
return m
}