Created
February 28, 2020 18:35
-
-
Save masroorhasan/53db16adda94e7f2209afc80de98d93a to your computer and use it in GitHub Desktop.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
package main | |
import ( | |
"context" | |
"flag" | |
"fmt" | |
"log" | |
"sync" | |
"time" | |
"github.com/coreos/etcd/clientv3/clientv3util" | |
"go.etcd.io/etcd/clientv3" | |
"go.etcd.io/etcd/clientv3/concurrency" | |
) | |
var ( | |
key = flag.String("key", "", "etcd key") | |
) | |
func doTxn(ctx context.Context, c *clientv3.Client, key, val string) (bool, error) { | |
// insert on key MISS | |
tr, err := c.Txn(ctx). | |
If(clientv3util.KeyMissing(key)). | |
Then( | |
clientv3.OpPut(key, val), | |
clientv3.OpGet(key, clientv3.WithLastRev()...), | |
).Else(clientv3.OpGet(key, clientv3.WithLastRev()...)). | |
Commit() | |
if err != nil { | |
log.Fatalf("failed to PUT txn on miss: %v", err) | |
return false, err | |
} | |
if tr.Succeeded { | |
log.Printf("MISS: %v", tr.Responses[0]) | |
return true, nil | |
} | |
// update on key HIT | |
newV := fmt.Sprintf("%s,%s", val, tr.Responses[0].GetResponseRange().Kvs[0].Value) | |
tr, err = c.Txn(ctx). | |
If( | |
clientv3.Compare(clientv3.ModRevision(key), "=", tr.Responses[0].GetResponseRange().Kvs[0].ModRevision), | |
). | |
Then( | |
clientv3.OpPut(key, newV), | |
clientv3.OpGet(key, clientv3.WithLastRev()...), | |
). | |
Commit() | |
if err != nil { | |
log.Fatalf("failed to PUT txn on hit: %v", err) | |
return false, err | |
} | |
return tr.Succeeded, nil | |
} | |
func doSTM(ctx context.Context, c *clientv3.Client, key, val string) (bool, error) { | |
stm := func(stm concurrency.STM) error { | |
oval := stm.Get(key) | |
if oval == "" { | |
stm.Put(key, val) | |
return nil | |
} | |
newV := fmt.Sprintf("%s,%s", val, oval) | |
stm.Put(key, newV) | |
return nil | |
} | |
tr, err := concurrency.NewSTM(c, stm) | |
if err != nil { | |
return false, err | |
} | |
return tr.Succeeded, nil | |
} | |
func main() { | |
ctx := context.Background() | |
c, err := clientv3.New(clientv3.Config{ | |
Endpoints: []string{"localhost:2379"}, | |
DialTimeout: 10 * time.Second, | |
}) | |
if err != nil { | |
log.Fatalf("failed to create etcd client: %v", err) | |
} | |
flag.Parse() | |
if *key == "" { | |
log.Fatalf("must specify key") | |
} | |
// do updates | |
wg := &sync.WaitGroup{} | |
for i := 0; i < 3; i++ { | |
wg.Add(1) | |
go func(id int) { | |
defer wg.Done() | |
val := fmt.Sprintf("%d", id) | |
fmt.Printf("put, key=%s, val=%s\n", *key, val) | |
ok, err := doTxn(ctx, c, *key, val) | |
if err != nil { | |
log.Fatalf("shit is fucked yo") | |
return | |
} | |
if ok { | |
log.Printf("successful put for key=%s val=%s\n", *key, val) | |
} else { | |
log.Print("y u no update") | |
} | |
}(i) | |
} | |
wg.Wait() | |
log.Print("done") | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment