traefik/provider/kv/kv.go
2018-07-11 09:08:03 +02:00

128 lines
3.7 KiB
Go

package kv
import (
"errors"
"fmt"
"strings"
"time"
"github.com/abronan/valkeyrie"
"github.com/abronan/valkeyrie/store"
"github.com/cenk/backoff"
"github.com/containous/traefik/job"
"github.com/containous/traefik/log"
"github.com/containous/traefik/provider"
"github.com/containous/traefik/safe"
"github.com/containous/traefik/types"
)
// Provider holds common configurations of key-value providers.
type Provider struct {
provider.BaseProvider `mapstructure:",squash" export:"true"`
Endpoint string `description:"Comma separated server endpoints"`
Prefix string `description:"Prefix used for KV store" export:"true"`
TLS *types.ClientTLS `description:"Enable TLS support" export:"true"`
Username string `description:"KV Username"`
Password string `description:"KV Password"`
storeType store.Backend
kvClient store.Store
}
// CreateStore create the K/V store
func (p *Provider) CreateStore() (store.Store, error) {
storeConfig := &store.Config{
ConnectionTimeout: 30 * time.Second,
Bucket: "traefik",
Username: p.Username,
Password: p.Password,
}
if p.TLS != nil {
var err error
storeConfig.TLS, err = p.TLS.CreateTLSConfig()
if err != nil {
return nil, err
}
}
return valkeyrie.NewStore(
p.storeType,
strings.Split(p.Endpoint, ","),
storeConfig,
)
}
// SetStoreType storeType setter
func (p *Provider) SetStoreType(storeType store.Backend) {
p.storeType = storeType
}
// SetKVClient kvClient setter
func (p *Provider) SetKVClient(kvClient store.Store) {
p.kvClient = kvClient
}
func (p *Provider) watchKv(configurationChan chan<- types.ConfigMessage, prefix string, stop chan bool) error {
operation := func() error {
events, err := p.kvClient.WatchTree(p.Prefix, make(chan struct{}), nil)
if err != nil {
return fmt.Errorf("failed to KV WatchTree: %v", err)
}
for {
select {
case <-stop:
return nil
case _, ok := <-events:
if !ok {
return errors.New("watchtree channel closed")
}
configuration := p.buildConfiguration()
if configuration != nil {
configurationChan <- types.ConfigMessage{
ProviderName: string(p.storeType),
Configuration: configuration,
}
}
}
}
}
notify := func(err error, time time.Duration) {
log.Errorf("KV connection error: %+v, retrying in %s", err, time)
}
err := backoff.RetryNotify(safe.OperationWithRecover(operation), job.NewBackOff(backoff.NewExponentialBackOff()), notify)
if err != nil {
return fmt.Errorf("cannot connect to KV server: %v", err)
}
return nil
}
// Provide provides the configuration to traefik via the configuration channel
func (p *Provider) Provide(configurationChan chan<- types.ConfigMessage, pool *safe.Pool) error {
operation := func() error {
if _, err := p.kvClient.Exists(p.Prefix+"/qmslkjdfmqlskdjfmqlksjazçueznbvbwzlkajzebvkwjdcqmlsfj", nil); err != nil {
return fmt.Errorf("failed to test KV store connection: %v", err)
}
if p.Watch {
pool.Go(func(stop chan bool) {
err := p.watchKv(configurationChan, p.Prefix, stop)
if err != nil {
log.Errorf("Cannot watch KV store: %v", err)
}
})
}
configuration := p.buildConfiguration()
configurationChan <- types.ConfigMessage{
ProviderName: string(p.storeType),
Configuration: configuration,
}
return nil
}
notify := func(err error, time time.Duration) {
log.Errorf("KV connection error: %+v, retrying in %s", err, time)
}
err := backoff.RetryNotify(safe.OperationWithRecover(operation), job.NewBackOff(backoff.NewExponentialBackOff()), notify)
if err != nil {
return fmt.Errorf("cannot connect to KV server: %v", err)
}
return nil
}