Add CompareFailErr for CAS operation error check (#15893)

Signed-off-by: NCongqi Xia <congqi.xia@zilliz.com>

internal/kv/etcd/embed_etcd_kv.go

@@ -30,6 +30,7 @@ import (
 	"go.uber.org/zap"
 
 	"github.com/milvus-io/milvus/internal/kv"
+	kvi "github.com/milvus-io/milvus/internal/kv"
 	"github.com/milvus-io/milvus/internal/log"
 )
 
@@ -549,7 +550,7 @@ func (kv *EmbedEtcdKV) CompareValueAndSwap(key, value, target string, opts ...cl
 		return err
 	}
 	if !resp.Succeeded {
-		return fmt.Errorf("function CompareValueAndSwap error for compare is false for key: %s", key)
+		return kvi.NewCompareFailedError(fmt.Errorf("function CompareValueAndSwap error for compare is false for key: %s", key))
 	}
 
 	return nil
@@ -570,7 +571,7 @@ func (kv *EmbedEtcdKV) CompareValueAndSwapBytes(key string, value, target []byte
 		return err
 	}
 	if !resp.Succeeded {
-		return fmt.Errorf("function CompareValueAndSwapBytes error for compare is false for key: %s", key)
+		return kvi.NewCompareFailedError(fmt.Errorf("function CompareValueAndSwapBytes error for compare is false for key: %s", key))
 	}
 
 	return nil
@@ -591,7 +592,7 @@ func (kv *EmbedEtcdKV) CompareVersionAndSwap(key string, version int64, target s
 		return err
 	}
 	if !resp.Succeeded {
-		return fmt.Errorf("function CompareAndSwap error for compare is false for key: %s", key)
+		return kvi.NewCompareFailedError(fmt.Errorf("function CompareAndSwap error for compare is false for key: %s", key))
 	}
 
 	return nil
@@ -612,7 +613,7 @@ func (kv *EmbedEtcdKV) CompareVersionAndSwapBytes(key string, version int64, tar
 		return err
 	}
 	if !resp.Succeeded {
-		return fmt.Errorf("function CompareVersionAndSwapBytes error for compare is false for key: %s", key)
+		return kvi.NewCompareFailedError(fmt.Errorf("function CompareVersionAndSwapBytes error for compare is false for key: %s", key))
 	}
 
 	return nil

internal/kv/etcd/embed_etcd_kv_test.go

@@ -17,9 +17,11 @@
 package etcdkv_test
 
 import (
+	"errors"
 	"os"
 	"testing"
 
+	"github.com/milvus-io/milvus/internal/kv"
 	"github.com/milvus-io/milvus/internal/util/metricsinfo"
 
 	embed_etcd_kv "github.com/milvus-io/milvus/internal/kv/etcd"
@@ -800,6 +802,7 @@ func TestEmbedEtcd(te *testing.T) {
 			assert.Equal(t, revision+1, resp.Header.Revision)
 		}
 
+		var compareErr *kv.CompareFailedError
 		err = metaKv.CompareVersionAndSwap("a/b/c", 0, "1")
 		assert.NoError(t, err)
 
@@ -809,12 +812,14 @@ func TestEmbedEtcd(te *testing.T) {
 
 		err = metaKv.CompareVersionAndSwap("a/b/c", 0, "1")
 		assert.Error(t, err)
+		assert.True(t, errors.As(err, &compareErr))
 
 		err = metaKv.CompareValueAndSwap("a/b/c", "1", "2")
 		assert.NoError(t, err)
 
 		err = metaKv.CompareValueAndSwap("a/b/c", "1", "2")
 		assert.Error(t, err)
+		assert.True(t, errors.As(err, &compareErr))
 	})
 
 	te.Run("Etcd Revision Bytes", func(t *testing.T) {
@@ -852,6 +857,7 @@ func TestEmbedEtcd(te *testing.T) {
 			assert.Equal(t, revision+1, resp.Header.Revision)
 		}
 
+		var compareErr *kv.CompareFailedError
 		err = metaKv.CompareVersionAndSwapBytes("a/b/c", 0, []byte("1"))
 		assert.NoError(t, err)
 
@@ -861,12 +867,15 @@ func TestEmbedEtcd(te *testing.T) {
 
 		err = metaKv.CompareVersionAndSwapBytes("a/b/c", 0, []byte("1"))
 		assert.Error(t, err)
+		assert.True(t, errors.As(err, &compareErr))
 
 		err = metaKv.CompareValueAndSwapBytes("a/b/c", []byte("1"), []byte("2"))
 		assert.NoError(t, err)
 
 		err = metaKv.CompareValueAndSwapBytes("a/b/c", []byte("1"), []byte("2"))
 		assert.Error(t, err)
+		assert.True(t, errors.As(err, &compareErr))
+
 	})
 
 	te.Run("Etcd Lease", func(t *testing.T) {

internal/kv/etcd/etcd_kv.go

@@ -22,6 +22,7 @@ import (
 	"path"
 	"time"
 
+	kvi "github.com/milvus-io/milvus/internal/kv"
 	"github.com/milvus-io/milvus/internal/log"
 	clientv3 "go.etcd.io/etcd/client/v3"
 
@@ -567,7 +568,7 @@ func (kv *EtcdKV) CompareValueAndSwap(key, value, target string, opts ...clientv
 		return err
 	}
 	if !resp.Succeeded {
-		return fmt.Errorf("function CompareAndSwap error for compare is false for key: %s", key)
+		return kvi.NewCompareFailedError(fmt.Errorf("function CompareAndSwap error for compare is false for key: %s", key))
 	}
 	CheckElapseAndWarn(start, "Slow etcd operation compare value and swap")
 	return nil
@@ -589,7 +590,7 @@ func (kv *EtcdKV) CompareValueAndSwapBytes(key string, value, target []byte, opt
 		return err
 	}
 	if !resp.Succeeded {
-		return fmt.Errorf("function CompareAndSwap error for compare is false for key: %s", key)
+		return kvi.NewCompareFailedError(fmt.Errorf("function CompareAndSwap error for compare is false for key: %s", key))
 	}
 	CheckElapseAndWarn(start, "Slow etcd operation compare value and swap")
 	return nil
@@ -611,8 +612,8 @@ func (kv *EtcdKV) CompareVersionAndSwap(key string, source int64, target string,
 		return err
 	}
 	if !resp.Succeeded {
-		return fmt.Errorf("function CompareAndSwap error for compare is false for key: %s,"+
-			" source version: %d, target version: %s", key, source, target)
+		return kvi.NewCompareFailedError(fmt.Errorf("function CompareAndSwap error for compare is false for key: %s,"+
+			" source version: %d, target version: %s", key, source, target))
 	}
 	CheckElapseAndWarn(start, "Slow etcd operation compare version and swap")
 	return nil
@@ -634,8 +635,8 @@ func (kv *EtcdKV) CompareVersionAndSwapBytes(key string, source int64, target []
 		return err
 	}
 	if !resp.Succeeded {
-		return fmt.Errorf("function CompareAndSwap error for compare is false for key: %s,"+
-			" source version: %d, target version: %s", key, source, target)
+		return kvi.NewCompareFailedError(fmt.Errorf("function CompareAndSwap error for compare is false for key: %s,"+
+			" source version: %d, target version: %s", key, source, target))
 	}
 	CheckElapseAndWarn(start, "Slow etcd operation compare version and swap")
 	return nil

internal/kv/etcd/etcd_kv_test.go

@@ -17,10 +17,12 @@
 package etcdkv_test
 
 import (
+	"errors"
 	"os"
 	"testing"
 	"time"
 
+	"github.com/milvus-io/milvus/internal/kv"
 	etcdkv "github.com/milvus-io/milvus/internal/kv/etcd"
 	"github.com/milvus-io/milvus/internal/util/etcd"
 	"github.com/milvus-io/milvus/internal/util/paramtable"
@@ -723,6 +725,7 @@ func TestEtcdKV_Load(te *testing.T) {
 			assert.Equal(t, revision+1, resp.Header.Revision)
 		}
 
+		var compareErr *kv.CompareFailedError
 		err = etcdKV.CompareVersionAndSwap("a/b/c", 0, "1")
 		assert.NoError(t, err)
 
@@ -732,12 +735,14 @@ func TestEtcdKV_Load(te *testing.T) {
 
 		err = etcdKV.CompareVersionAndSwap("a/b/c", 0, "1")
 		assert.Error(t, err)
+		assert.True(t, errors.As(err, &compareErr))
 
 		err = etcdKV.CompareValueAndSwap("a/b/c", "1", "2")
 		assert.NoError(t, err)
 
 		err = etcdKV.CompareValueAndSwap("a/b/c", "1", "2")
 		assert.Error(t, err)
+		assert.True(t, errors.As(err, &compareErr))
 	})
 
 	te.Run("Etcd Revision Bytes", func(t *testing.T) {
@@ -772,6 +777,7 @@ func TestEtcdKV_Load(te *testing.T) {
 			assert.Equal(t, revision+1, resp.Header.Revision)
 		}
 
+		var compareErr *kv.CompareFailedError
 		err = etcdKV.CompareVersionAndSwapBytes("a/b/c", 0, []byte("1"))
 		assert.NoError(t, err)
 
@@ -781,12 +787,14 @@ func TestEtcdKV_Load(te *testing.T) {
 
 		err = etcdKV.CompareVersionAndSwapBytes("a/b/c", 0, []byte("1"))
 		assert.Error(t, err)
+		assert.True(t, errors.As(err, &compareErr))
 
 		err = etcdKV.CompareValueAndSwapBytes("a/b/c", []byte("1"), []byte("2"))
 		assert.NoError(t, err)
 
 		err = etcdKV.CompareValueAndSwapBytes("a/b/c", []byte("1"), []byte("2"))
 		assert.Error(t, err)
+		assert.True(t, errors.As(err, &compareErr))
 	})
 
 	te.Run("Etcd Lease", func(t *testing.T) {

internal/kv/kv.go

@@ -21,6 +21,21 @@ import (
 	clientv3 "go.etcd.io/etcd/client/v3"
 )
 
+// CompareFailedError is a helper type for checking MetaKv CompareAndSwap series func error type
+type CompareFailedError struct {
+	internalError error
+}
+
+// Error implements error interface
+func (e *CompareFailedError) Error() string {
+	return e.internalError.Error()
+}
+
+// NewCompareFailedError wraps error into NewCompareFailedError
+func NewCompareFailedError(err error) error {
+	return &CompareFailedError{internalError: err}
+}
+
 // BaseKV contains base operations of kv. Include save, load and remove.
 type BaseKV interface {
 	Load(key string) (string, error)