parcoursmob/utils/storage/etcd.go

164 lines
3.8 KiB
Go

package storage
import (
"bytes"
"context"
"encoding/gob"
"encoding/json"
"fmt"
"time"
"github.com/spf13/viper"
clientv3 "go.etcd.io/etcd/client/v3"
"go.etcd.io/etcd/client/v3/namespace"
)
type EtcdSerializer interface {
Deserialize(d []byte, m *any) error
Serialize(m any) ([]byte, error)
}
type JSONEtcdSerializer struct{}
// Serialize to JSON. Will err if there are unmarshalable key values
func (s JSONEtcdSerializer) Serialize(m any) ([]byte, error) {
return json.Marshal(m)
}
// Deserialize back to map[string]interface{}
func (s JSONEtcdSerializer) Deserialize(d []byte, m *any) (err error) {
err = json.Unmarshal(d, &m)
if err != nil {
fmt.Printf("JSONSerializer.deserialize() Error: %v", err)
return err
}
return
}
// GobEtcdSerializer uses gob package to encode the session map
type GobEtcdSerializer struct{}
// Serialize using gob
func (s GobEtcdSerializer) Serialize(m any) ([]byte, error) {
buf := new(bytes.Buffer)
enc := gob.NewEncoder(buf)
err := enc.Encode(m)
if err == nil {
return buf.Bytes(), nil
}
return nil, err
}
// Deserialize back to map[interface{}]interface{}
func (s GobEtcdSerializer) Deserialize(d []byte, m any) error {
dec := gob.NewDecoder(bytes.NewBuffer(d))
return dec.Decode(&m)
}
type EtcdHandler struct {
*clientv3.Client
serializer EtcdSerializer
}
func NewEtcdHandler(cfg *viper.Viper) (*EtcdHandler, error) {
var (
endpoints = cfg.GetStringSlice("storage.kv.etcd.endpoints")
prefix = cfg.GetString("storage.kv.etcd.prefix")
username = cfg.GetString("storage.kv.etcd.username")
password = cfg.GetString("storage.kv.etcd.password")
)
cli, err := clientv3.New(clientv3.Config{
Endpoints: endpoints,
Username: username,
Password: password,
DialTimeout: 5 * time.Second,
})
if err != nil {
fmt.Println(err)
return nil, err
}
cli.KV = namespace.NewKV(cli.KV, prefix)
cli.Watcher = namespace.NewWatcher(cli.Watcher, prefix)
cli.Lease = namespace.NewLease(cli.Lease, prefix)
return &EtcdHandler{
Client: cli,
serializer: JSONEtcdSerializer{},
}, nil
}
func (s *EtcdHandler) Put(k string, v any) error {
data, err := s.serializer.Serialize(v)
if err != nil {
fmt.Println(err)
return err
}
// _, err = s.Client.KV.Put(context.TODO(), k, data.String())
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
_, err = s.Client.KV.Put(ctx, k, string(data))
cancel()
if err != nil {
fmt.Println(err)
return err
}
return nil
}
func (s *EtcdHandler) PutWithTTL(k string, v any, duration time.Duration) error {
lease, err := s.Client.Lease.Grant(context.TODO(), int64(duration.Seconds()))
if err != nil {
fmt.Println(err)
return err
}
data, err := s.serializer.Serialize(v)
if err != nil {
fmt.Println(err)
return err
}
// _, err = s.Client.KV.Put(context.TODO(), k, data.String(), clientv3.WithLease(lease.ID))
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
_, err = s.Client.KV.Put(ctx, k, string(data), clientv3.WithLease(lease.ID))
cancel()
if err != nil {
fmt.Println(err)
return err
}
return nil
}
func (s *EtcdHandler) Get(k string) (any, error) {
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
resp, err := s.Client.KV.Get(ctx, k)
cancel()
if err != nil {
fmt.Println(err)
return nil, err
}
for _, v := range resp.Kvs {
var data any
err := s.serializer.Deserialize([]byte(v.Value), &data)
if err != nil {
fmt.Println(err)
return nil, err
}
// We return directly as we want to last revision of value
return data, nil
}
return nil, fmt.Errorf("no value %v", k)
}
func (s *EtcdHandler) Delete(k string) error {
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
_, err := s.Client.KV.Delete(ctx, k)
cancel()
if err != nil {
fmt.Println(err)
return err
}
return nil
}