traefik/provider/kv.go
Emile Vauge bcc5f24c0f
Add GoSafe goroutine launch
Signed-off-by: Emile Vauge <emile@vauge.com>
2016-04-01 14:01:31 +02:00

182 lines
4.6 KiB
Go

// Package provider holds the different provider implementation.
package provider
import (
"crypto/tls"
"crypto/x509"
"fmt"
"io/ioutil"
"strings"
"text/template"
"time"
"github.com/BurntSushi/ty/fun"
log "github.com/Sirupsen/logrus"
"github.com/containous/traefik/safe"
"github.com/containous/traefik/types"
"github.com/docker/libkv"
"github.com/docker/libkv/store"
)
// Kv holds common configurations of key-value providers.
type Kv struct {
BaseProvider `mapstructure:",squash"`
Endpoint string
Prefix string
TLS *KvTLS
storeType store.Backend
kvclient store.Store
}
// KvTLS holds TLS specific configurations
type KvTLS struct {
CA string
Cert string
Key string
InsecureSkipVerify bool
}
func (provider *Kv) watchKv(configurationChan chan<- types.ConfigMessage, prefix string) {
for {
chanKeys, err := provider.kvclient.WatchTree(provider.Prefix, make(chan struct{}) /* stop chan */)
if err != nil {
log.Errorf("Failed to WatchTree %s", err)
continue
}
for range chanKeys {
configuration := provider.loadConfig()
if configuration != nil {
configurationChan <- types.ConfigMessage{
ProviderName: string(provider.storeType),
Configuration: configuration,
}
}
}
log.Warnf("Intermittent failure to WatchTree KV. Retrying.")
}
}
func (provider *Kv) provide(configurationChan chan<- types.ConfigMessage) error {
storeConfig := &store.Config{
ConnectionTimeout: 30 * time.Second,
Bucket: "traefik",
}
if provider.TLS != nil {
caPool := x509.NewCertPool()
if provider.TLS.CA != "" {
ca, err := ioutil.ReadFile(provider.TLS.CA)
if err != nil {
return fmt.Errorf("Failed to read CA. %s", err)
}
caPool.AppendCertsFromPEM(ca)
}
cert, err := tls.LoadX509KeyPair(provider.TLS.Cert, provider.TLS.Key)
if err != nil {
return fmt.Errorf("Failed to load keypair. %s", err)
}
storeConfig.TLS = &tls.Config{
Certificates: []tls.Certificate{cert},
RootCAs: caPool,
InsecureSkipVerify: provider.TLS.InsecureSkipVerify,
}
}
kv, err := libkv.NewStore(
provider.storeType,
strings.Split(provider.Endpoint, ","),
storeConfig,
)
if err != nil {
return err
}
if _, err := kv.List(""); err != nil {
return err
}
provider.kvclient = kv
if provider.Watch {
safe.Go(func() {
provider.watchKv(configurationChan, provider.Prefix)
})
}
configuration := provider.loadConfig()
configurationChan <- types.ConfigMessage{
ProviderName: string(provider.storeType),
Configuration: configuration,
}
return nil
}
func (provider *Kv) loadConfig() *types.Configuration {
templateObjects := struct {
Prefix string
}{
// Allow `/traefik/alias` to superesede `provider.Prefix`
strings.TrimSuffix(provider.get(provider.Prefix, provider.Prefix+"/alias"), "/"),
}
var KvFuncMap = template.FuncMap{
"List": provider.list,
"Get": provider.get,
"SplitGet": provider.splitGet,
"Last": provider.last,
}
configuration, err := provider.getConfiguration("templates/kv.tmpl", KvFuncMap, templateObjects)
if err != nil {
log.Error(err)
}
return configuration
}
func (provider *Kv) list(keys ...string) []string {
joinedKeys := strings.Join(keys, "")
keysPairs, err := provider.kvclient.List(joinedKeys)
if err != nil {
log.Errorf("Error getting keys %s %s ", joinedKeys, err)
return nil
}
directoryKeys := make(map[string]string)
for _, key := range keysPairs {
directory := strings.Split(strings.TrimPrefix(key.Key, strings.TrimPrefix(joinedKeys, "/")), "/")[0]
directoryKeys[directory] = joinedKeys + directory
}
return fun.Values(directoryKeys).([]string)
}
func (provider *Kv) get(defaultValue string, keys ...string) string {
joinedKeys := strings.Join(keys, "")
keyPair, err := provider.kvclient.Get(joinedKeys)
if err != nil {
log.Warnf("Error getting key %s %s, setting default %s", joinedKeys, err, defaultValue)
return defaultValue
} else if keyPair == nil {
log.Warnf("Error getting key %s, setting default %s", joinedKeys, defaultValue)
return defaultValue
}
return string(keyPair.Value)
}
func (provider *Kv) splitGet(keys ...string) []string {
joinedKeys := strings.Join(keys, "")
keyPair, err := provider.kvclient.Get(joinedKeys)
if err != nil {
log.Warnf("Error getting key %s %s, setting default empty", joinedKeys, err)
return []string{}
} else if keyPair == nil {
log.Warnf("Error getting key %s, setting default %empty", joinedKeys)
return []string{}
}
return strings.Split(string(keyPair.Value), ",")
}
func (provider *Kv) last(key string) string {
splittedKey := strings.Split(key, "/")
return splittedKey[len(splittedKey)-1]
}