fix: ens error handling (#5213)

Author: nugaon

pkg/api/api.go

@@ -43,6 +43,7 @@ import (
 	"github.com/ethersphere/bee/v2/pkg/pss"
 	"github.com/ethersphere/bee/v2/pkg/resolver"
 	"github.com/ethersphere/bee/v2/pkg/resolver/client/ens"
+	"github.com/ethersphere/bee/v2/pkg/resolver/multiresolver"
 	"github.com/ethersphere/bee/v2/pkg/sctx"
 	"github.com/ethersphere/bee/v2/pkg/settlement"
 	"github.com/ethersphere/bee/v2/pkg/settlement/swap"
@@ -109,9 +110,8 @@ const (
 )
 
 const (
-	multiPartFormData  = "multipart/form-data"
-	contentTypeTar     = "application/x-tar"
-	boolHeaderSetValue = "true"
+	multiPartFormData = "multipart/form-data"
+	contentTypeTar    = "application/x-tar"
 )
 
 var (
@@ -449,6 +449,10 @@ func (s *Service) resolveNameOrAddress(str string) (swarm.Address, error) {
 		return addr, nil
 	}
 
+	if errors.Is(err, multiresolver.ErrResolverService) || errors.Is(err, resolver.ErrServiceNotAvailable) {
+		return swarm.ZeroAddress, err
+	}
+
 	return swarm.ZeroAddress, fmt.Errorf("%w: %w", errInvalidNameOrAddress, err)
 }
 
@@ -651,13 +655,23 @@ func (s *Service) mapStructure(input, output interface{}) func(string, log.Logge
 				Message: msg,
 				Code:    http.StatusBadRequest,
 			}
+			hasServiceUnavailable := false
 			for _, err := range merr.Errors {
+				if errors.Is(err, resolver.ErrServiceNotAvailable) {
+					hasServiceUnavailable = true
+					resp.Reasons = append(resp.Reasons, jsonhttp.Reason{
+						Field: "address",
+						Error: err.Error(),
+					})
+					continue
+				}
 				var perr *parseError
 				if errors.As(err, &perr) {
 					resp.Reasons = append(resp.Reasons, jsonhttp.Reason{
 						Field: perr.Entry,
 						Error: perr.Cause.Error(),
 					})
+					continue
 				}
 				var verr *validationError
 				if errors.As(err, &verr) {
@@ -667,7 +681,14 @@ func (s *Service) mapStructure(input, output interface{}) func(string, log.Logge
 					})
 				}
 			}
-			jsonhttp.BadRequest(w, resp)
+
+			if hasServiceUnavailable {
+				resp.Message = "service unavailable"
+				resp.Code = http.StatusServiceUnavailable
+				jsonhttp.ServiceUnavailable(w, resp)
+			} else {
+				jsonhttp.BadRequest(w, resp)
+			}
 		}
 	}
 

pkg/resolver/client/ens/ens.go

@@ -167,10 +167,10 @@ func wrapDial(endpoint, contractAddr string) (*ethclient.Client, *goens.Registry
 }
 
 func wrapResolve(registry *goens.Registry, _ common.Address, name string) (string, error) {
-	// Ensure the name is registered.
 	ownerAddress, err := registry.Owner(name)
+	// it returns error only if the service is not available
 	if err != nil {
-		return "", fmt.Errorf("owner: %w: %w", err, resolver.ErrNotFound)
+		return "", fmt.Errorf("%w: %w", resolver.ErrServiceNotAvailable, err)
 	}
 
 	// If the name is not registered, return an error.
@@ -181,12 +181,16 @@ func wrapResolve(registry *goens.Registry, _ common.Address, name string) (strin
 	// Obtain the resolver for this domain name.
 	ensR, err := registry.Resolver(name)
 	if err != nil {
-		return "", fmt.Errorf("resolver: %w: %w", err, resolver.ErrServiceNotAvailable)
+		return "", fmt.Errorf("%w: %w", resolver.ErrServiceNotAvailable, err)
 	}
 
 	// Try and read out the content hash record.
 	ch, err := ensR.Contenthash()
 	if err != nil {
+		// Check if it's a service error (rate limiting, network issues)
+		if strings.Contains(err.Error(), "429") || strings.Contains(err.Error(), "rate limit") {
+			return "", fmt.Errorf("%w: %w", resolver.ErrServiceNotAvailable, err)
+		}
 		return "", fmt.Errorf("contenthash: %w: %w", err, resolver.ErrInvalidContentHash)
 	}
 

pkg/resolver/multiresolver/multiresolver.go

@@ -14,6 +14,7 @@ import (
 	"github.com/ethersphere/bee/v2/pkg/resolver"
 	"github.com/ethersphere/bee/v2/pkg/resolver/cidv1"
 	"github.com/ethersphere/bee/v2/pkg/resolver/client/ens"
+	"github.com/ethersphere/bee/v2/pkg/swarm"
 	"github.com/hashicorp/go-multierror"
 )
 
@@ -35,6 +36,8 @@ var (
 	ErrResolverChainFailed = errors.New("resolver chain failed")
 	// ErrCloseFailed denotes that closing the multiresolver failed.
 	ErrCloseFailed = errors.New("close failed")
+	// ErrResolverService denotes that no resolver service is configured for the requested name or the resolver service is not available.
+	ErrResolverService = errors.New("cannot communicate with the resolver or no resolver service configured")
 )
 
 type resolverMap map[string][]resolver.Interface
@@ -160,6 +163,9 @@ func (mr *MultiResolver) Resolve(name string) (addr resolver.Address, err error)
 	// If no resolver chain is found, switch to the default chain.
 	if len(chain) == 0 {
 		chain = mr.resolvers[""]
+		if len(chain) == 1 && tld != "" { // only the CID resolver is defined
+			return swarm.ZeroAddress, resolver.ErrServiceNotAvailable
+		}
 	}
 
 	var errs *multierror.Error

pkg/resolver/multiresolver/multiresolver_test.go

@@ -217,7 +217,7 @@ func TestResolve(t *testing.T) {
 		},
 		{
 			// Switch to the default chain:
-			name:    "this.empty",
+			name:    "defaultChainIsCidTriggerItWithoutTld",
 			wantAdr: addr,
 		},
 		{

pkg/resolver/resolver.go

@@ -20,7 +20,7 @@ var (
 	// ErrNotFound denotes that given name was not found
 	ErrNotFound = errors.New("not found")
 	// ErrServiceNotAvailable denotes that remote ENS service is not available
-	ErrServiceNotAvailable = errors.New("not available")
+	ErrServiceNotAvailable = errors.New("ENS service is not available")
 	// ErrInvalidContentHash denotes that the value of the response contenthash record is not valid.
 	ErrInvalidContentHash = errors.New("invalid swarm content hash")
 )