feat: add getset command in redis and kv (#1693)

core/stores/kv/store.go

@@ -54,6 +54,7 @@ type (
 		Setex(key, value string, seconds int) error
 		Setnx(key, value string) (bool, error)
 		SetnxEx(key, value string, seconds int) (bool, error)
+		Getset(key, value string) (string, error)
 		Sismember(key string, value interface{}) (bool, error)
 		Smembers(key string) ([]string, error)
 		Spop(key string) (string, error)
@@ -459,6 +460,15 @@ func (cs clusterStore) SetnxEx(key, value string, seconds int) (bool, error) {
 	return node.SetnxEx(key, value, seconds)
 }
 
+func (cs clusterStore) Getset(key, value string) (string, error) {
+	node, err := cs.getRedis(key)
+	if err != nil {
+		return "", err
+	}
+
+	return node.GetSet(key, value)
+}
+
 func (cs clusterStore) Sismember(key string, value interface{}) (bool, error) {
 	node, err := cs.getRedis(key)
 	if err != nil {

core/stores/kv/store_test.go

@@ -490,6 +490,29 @@ func TestRedis_SetExNx(t *testing.T) {
 	})
 }
 
+func TestRedis_Getset(t *testing.T) {
+	store := clusterStore{dispatcher: hash.NewConsistentHash()}
+	_, err := store.Getset("hello", "world")
+	assert.NotNil(t, err)
+
+	runOnCluster(t, func(client Store) {
+		val, err := client.Getset("hello", "world")
+		assert.Nil(t, err)
+		assert.Equal(t, "", val)
+		val, err = client.Get("hello")
+		assert.Nil(t, err)
+		assert.Equal(t, "world", val)
+		val, err = client.Getset("hello", "newworld")
+		assert.Nil(t, err)
+		assert.Equal(t, "world", val)
+		val, err = client.Get("hello")
+		assert.Nil(t, err)
+		assert.Equal(t, "newworld", val)
+		_, err = client.Del("hello")
+		assert.Nil(t, err)
+	})
+}
+
 func TestRedis_SetGetDelHashField(t *testing.T) {
 	store := clusterStore{dispatcher: hash.NewConsistentHash()}
 	err := store.Hset("key", "field", "value")