[#125] Updated error handling

Signed-off-by: Denis Kirillov <denis@nspcc.ru>

api/handler/head.go

@@ -3,14 +3,13 @@ package handler
 import (
 	"bytes"
 	"context"
+	"errors"
 	"net/http"
 
 	"github.com/gorilla/mux"
 	"github.com/nspcc-dev/neofs-s3-gw/api"
 	"github.com/nspcc-dev/neofs-s3-gw/api/layer"
 	"go.uber.org/zap"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/status"
 )
 
 const sizeToDetectType = 512
@@ -125,13 +124,8 @@ func (h *handler) HeadBucketHandler(w http.ResponseWriter, r *http.Request) {
 			zap.Error(err))
 
 		code := http.StatusBadRequest
-		if st, ok := status.FromError(err); ok && st != nil {
-			switch st.Code() { //nolint:exhaustive // we have default value set above
-			case codes.NotFound:
-				code = http.StatusNotFound
-			case codes.PermissionDenied:
-				code = http.StatusForbidden
-			}
+		if errors.Is(err, layer.ErrBucketNotFound) {
+			code = http.StatusNotFound
 		}
 
 		api.WriteResponse(w, code, nil, api.MimeNone)

api/handler/put.go

@@ -100,6 +100,7 @@ func (h *handler) CreateBucketHandler(w http.ResponseWriter, r *http.Request) {
 			Description:    err.Error(),
 			HTTPStatusCode: http.StatusBadRequest,
 		}, r.URL)
+		return
 	}
 
 	p.Policy, err = policy.Parse(defaultPolicy)
@@ -113,6 +114,7 @@ func (h *handler) CreateBucketHandler(w http.ResponseWriter, r *http.Request) {
 			Description:    err.Error(),
 			HTTPStatusCode: http.StatusBadRequest,
 		}, r.URL)
+		return
 	}
 
 	cid, err := h.obj.CreateBucket(r.Context(), &p)

api/layer/container.go

@@ -5,6 +5,7 @@ import (
 	"crypto/ecdsa"
 	"fmt"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
@@ -58,6 +59,9 @@ func (n *layer) containerInfo(ctx context.Context, cid *cid.ID) (*BucketInfo, er
 			zap.String("request_id", rid),
 			zap.Error(err))
 
+		if strings.Contains(err.Error(), "container not found") {
+			return nil, ErrBucketNotFound
+		}
 		return nil, err
 	}
 

api/layer/layer.go

@@ -129,6 +129,8 @@ var (
 	ErrObjectNotExists = errors.New("object not exists")
 	// ErrBucketAlreadyExists is returned on attempts to create already existing bucket.
 	ErrBucketAlreadyExists = errors.New("bucket exists")
+	// ErrBucketNotFound is returned on attempts to get not existing bucket.
+	ErrBucketNotFound = errors.New("bucket not found")
 )
 
 const (
@@ -198,7 +200,7 @@ func (n *layer) GetBucketInfo(ctx context.Context, name string) (*BucketInfo, er
 			}
 		}
 
-		return nil, status.Error(codes.NotFound, "bucket not found")
+		return nil, ErrBucketNotFound
 	}
 
 	return n.containerInfo(ctx, containerID)
@@ -495,9 +497,7 @@ func (n *layer) DeleteObjects(ctx context.Context, bucket string, objects []stri
 func (n *layer) CreateBucket(ctx context.Context, p *CreateBucketParams) (*cid.ID, error) {
 	_, err := n.GetBucketInfo(ctx, p.Name)
 	if err != nil {
-		errMsg := err.Error()
-		if strings.Contains(errMsg, "bucket not found") ||
-			strings.Contains(errMsg, "container not found") {
+		if errors.Is(err, ErrBucketNotFound) {
 			return n.createContainer(ctx, p)
 		}
 		return nil, err