[#74] tree: Simplify retry

Signed-off-by: Denis Kirillov <d.kirillov@yadro.com>

internal/frostfs/services/tree_client_grpc.go

@@ -73,7 +73,7 @@ type ServiceClientGRPC struct {
 	key        *keys.PrivateKey
 	log        *zap.Logger
 	clients    []treeClient
-	startIndex atomic.Int32
+	startIndex int32
 }
 
 type treeClient struct {
@@ -146,11 +146,12 @@ func (c *ServiceClientGRPC) GetNodes(ctx context.Context, p *tree.GetNodesParams
 		return nil, err
 	}
 
-	resp, err := requestWithRetry(ctx, request, c, func(client treeClient) grpcFunc[*grpcService.GetNodeByPathRequest, *grpcService.GetNodeByPathResponse] {
+	var resp *grpcService.GetNodeByPathResponse
-		return client.service.GetNodeByPath
+	if err := c.requestWithRetry(func(client treeClient) (inErr error) {
-	})
+		resp, inErr = client.service.GetNodeByPath(ctx, request)
-	if err != nil {
+		return handleError("failed to get node by path", inErr)
-		return nil, handleError("failed to get node by path", err)
+	}); err != nil {
+		return nil, err
 	}
 
 	res := make([]tree.NodeResponse, len(resp.GetBody().GetNodes()))
@@ -181,11 +182,12 @@ func (c *ServiceClientGRPC) GetSubTree(ctx context.Context, bktInfo *data.Bucket
 		return nil, err
 	}
 
-	cli, err := requestWithRetry(ctx, request, c, func(client treeClient) grpcFunc[*grpcService.GetSubTreeRequest, grpcService.TreeService_GetSubTreeClient] {
+	var cli grpcService.TreeService_GetSubTreeClient
-		return client.service.GetSubTree
+	if err := c.requestWithRetry(func(client treeClient) (inErr error) {
-	})
+		cli, inErr = client.service.GetSubTree(ctx, request)
-	if err != nil {
+		return handleError("failed to get sub tree client", inErr)
-		return nil, handleError("failed to get sub tree client", err)
+	}); err != nil {
+		return nil, err
 	}
 
 	var subtree []tree.NodeResponse
@@ -221,11 +223,12 @@ func (c *ServiceClientGRPC) AddNode(ctx context.Context, bktInfo *data.BucketInf
 		return 0, err
 	}
 
-	resp, err := requestWithRetry(ctx, request, c, func(client treeClient) grpcFunc[*grpcService.AddRequest, *grpcService.AddResponse] {
+	var resp *grpcService.AddResponse
-		return client.service.Add
+	if err := c.requestWithRetry(func(client treeClient) (inErr error) {
-	})
+		resp, inErr = client.service.Add(ctx, request)
-	if err != nil {
+		return handleError("failed to add node", inErr)
-		return 0, handleError("failed to add node", err)
+	}); err != nil {
+		return 0, err
 	}
 
 	return resp.GetBody().GetNodeId(), nil
@@ -252,11 +255,12 @@ func (c *ServiceClientGRPC) AddNodeByPath(ctx context.Context, bktInfo *data.Buc
 		return 0, err
 	}
 
-	resp, err := requestWithRetry(ctx, request, c, func(client treeClient) grpcFunc[*grpcService.AddByPathRequest, *grpcService.AddByPathResponse] {
+	var resp *grpcService.AddByPathResponse
-		return client.service.AddByPath
+	if err := c.requestWithRetry(func(client treeClient) (inErr error) {
-	})
+		resp, inErr = client.service.AddByPath(ctx, request)
-	if err != nil {
+		return handleError("failed to add node by path", inErr)
-		return 0, handleError("failed to add node by path", err)
+	}); err != nil {
+		return 0, err
 	}
 
 	body := resp.GetBody()
@@ -291,14 +295,12 @@ func (c *ServiceClientGRPC) MoveNode(ctx context.Context, bktInfo *data.BucketIn
 		return err
 	}
 
-	_, err := requestWithRetry(ctx, request, c, func(client treeClient) grpcFunc[*grpcService.MoveRequest, *grpcService.MoveResponse] {
+	return c.requestWithRetry(func(client treeClient) error {
-		return client.service.Move
+		if _, err := client.service.Move(ctx, request); err != nil {
-	})
-	if err != nil {
 			return handleError("failed to move node", err)
 		}
-
 		return nil
+	})
 }
 
 func (c *ServiceClientGRPC) RemoveNode(ctx context.Context, bktInfo *data.BucketInfo, treeID string, nodeID uint64) error {
@@ -319,31 +321,27 @@ func (c *ServiceClientGRPC) RemoveNode(ctx context.Context, bktInfo *data.Bucket
 		return err
 	}
 
-	_, err := requestWithRetry(ctx, request, c, func(cl treeClient) grpcFunc[*grpcService.RemoveRequest, *grpcService.RemoveResponse] {
+	return c.requestWithRetry(func(client treeClient) error {
-		return cl.service.Remove
+		if _, err := client.service.Remove(ctx, request); err != nil {
-	})
-	if err != nil {
 			return handleError("failed to remove node", err)
 		}
-
 		return nil
+	})
 }
 
-type grpcFunc[Req any, Resp any] func(context.Context, Req, ...grpc.CallOption) (Resp, error)
+func (c *ServiceClientGRPC) requestWithRetry(fn func(client treeClient) error) (err error) {
-
+	start := int(atomic.LoadInt32(&c.startIndex))
-func requestWithRetry[Req any, Resp any](ctx context.Context, req Req, c *ServiceClientGRPC, fn func(client treeClient) grpcFunc[Req, Resp]) (res Resp, err error) {
-	start := int(c.startIndex.Load())
 	for i := start; i < start+len(c.clients); i++ {
 		index := i % len(c.clients)
-		res, err = fn(c.clients[index])(ctx, req)
+		err = fn(c.clients[index])
 		if !shouldTryAgain(err) {
-			c.startIndex.Store(int32(index))
+			atomic.StoreInt32(&c.startIndex, int32(index))
-			return res, err
+			return err
 		}
 		c.log.Debug("tree request error", zap.String("address", c.clients[index].address), zap.Error(err))
 	}
 
-	return res, err
+	return err
 }
 
 func shouldTryAgain(err error) bool {
@@ -396,6 +394,9 @@ func getBearer(ctx context.Context, bktInfo *data.BucketInfo) []byte {
 }
 
 func handleError(msg string, err error) error {
+	if err == nil {
+		return nil
+	}
 	if strings.Contains(err.Error(), "not found") {
 		return fmt.Errorf("%w: %s", tree.ErrNodeNotFound, err.Error())
 	} else if strings.Contains(err.Error(), "is denied by") {

internal/frostfs/services/tree_client_grpc_test.go

@@ -1,14 +1,13 @@
 package services
 
 import (
-	"context"
 	"errors"
+	"sync/atomic"
 	"testing"
 
 	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/api/layer"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/zap/zaptest"
-	"google.golang.org/grpc"
 )
 
 func TestHandleError(t *testing.T) {
@@ -38,8 +37,6 @@ func TestHandleError(t *testing.T) {
 }
 
 func TestRetry(t *testing.T) {
-	ctx := context.Background()
-
 	cl := &ServiceClientGRPC{
 		log: zaptest.NewLogger(t),
 		clients: []treeClient{
@@ -50,51 +47,46 @@ func TestRetry(t *testing.T) {
 		},
 	}
 
-	fn := func(client treeClient) grpcFunc[[]string, string] {
+	makeFn := func(shouldFail []string) func(treeClient) error {
-		return func(ctx context.Context, shouldFail []string, opts ...grpc.CallOption) (string, error) {
+		return func(client treeClient) error {
 			for _, item := range shouldFail {
 				if item == client.address {
-					return "", errors.New("not found")
+					return errors.New("not found")
 				}
 			}
-			return client.address, nil
+			return nil
 		}
 	}
 
 	t.Run("first ok", func(t *testing.T) {
-		resp, err := requestWithRetry(ctx, []string{}, cl, fn)
+		err := cl.requestWithRetry(makeFn([]string{}))
 		require.NoError(t, err)
-		require.Equal(t, "node0", resp)
+		require.Equal(t, 0, int(atomic.LoadInt32(&cl.startIndex)))
-		require.Equal(t, 0, int(cl.startIndex.Load()))
+		atomic.StoreInt32(&cl.startIndex, 0)
-		cl.startIndex.Store(0)
 	})
 
 	t.Run("first failed", func(t *testing.T) {
-		resp, err := requestWithRetry(ctx, []string{"node0"}, cl, fn)
+		err := cl.requestWithRetry(makeFn([]string{"node0"}))
 		require.NoError(t, err)
-		require.Equal(t, "node1", resp)
+		require.Equal(t, 1, int(atomic.LoadInt32(&cl.startIndex)))
-		require.Equal(t, 1, int(cl.startIndex.Load()))
+		atomic.StoreInt32(&cl.startIndex, 0)
-		cl.startIndex.Store(0)
 	})
 
 	t.Run("all failed", func(t *testing.T) {
-		resp, err := requestWithRetry(ctx, []string{"node0", "node1", "node2", "node3"}, cl, fn)
+		err := cl.requestWithRetry(makeFn([]string{"node0", "node1", "node2", "node3"}))
 		require.Error(t, err)
-		require.Equal(t, "", resp)
+		require.Equal(t, 0, int(atomic.LoadInt32(&cl.startIndex)))
-		require.Equal(t, 0, int(cl.startIndex.Load()))
+		atomic.StoreInt32(&cl.startIndex, 0)
-		cl.startIndex.Store(0)
 	})
 
 	t.Run("round", func(t *testing.T) {
-		resp, err := requestWithRetry(ctx, []string{"node0", "node1"}, cl, fn)
+		err := cl.requestWithRetry(makeFn([]string{"node0", "node1"}))
 		require.NoError(t, err)
-		require.Equal(t, "node2", resp)
+		require.Equal(t, 2, int(atomic.LoadInt32(&cl.startIndex)))
-		require.Equal(t, 2, int(cl.startIndex.Load()))
 
-		resp, err = requestWithRetry(ctx, []string{"node2", "node3"}, cl, fn)
+		err = cl.requestWithRetry(makeFn([]string{"node2", "node3"}))
 		require.NoError(t, err)
-		require.Equal(t, "node0", resp)
+		require.Equal(t, 0, int(atomic.LoadInt32(&cl.startIndex)))
-		require.Equal(t, 0, int(cl.startIndex.Load()))
+		atomic.StoreInt32(&cl.startIndex, 0)
-		cl.startIndex.Store(0)
 	})
 }