feat: Add support for string-based namespaces from gRPC clients

edgraph/namespace.go

@@ -310,7 +310,7 @@ func getNamespaceIDFromName(ctx context.Context, nsName string) (uint64, error)
 		return 0, err
 	}
 	if len(data.Namespaces) == 0 {
-		return 0, errors.Errorf("namespace %q not found", nsName)
+		return 0, errors.Wrapf(x.ErrNamespaceNotFound, "namespace %q not found", nsName)
 	}
 
 	glog.Infof("Found namespace [%v] with id [%d]", nsName, data.Namespaces[0].ID)

edgraph/server.go

@@ -1194,7 +1194,26 @@
 
 // Query handles queries or mutations
 func (s *Server) QueryNoGrpc(ctx context.Context, req *api.Request) (*api.Response, error) {
-	ctx = x.AttachJWTNamespace(ctx)
+	// If the `namespace-str` is present in the metadata, use it to attach the namespace
+	// otherwise, use the namespace from the JWT.
+	var attached bool
+	nsStr, _ := x.ExtractNamespaceStr(ctx)
+	if nsStr != "" {
+		ns, err := getNamespaceIDFromName(x.AttachNamespace(ctx, x.RootNamespace), nsStr)
+		if err == nil {
+			ctx = x.AttachNamespace(ctx, ns)
+			attached = true
+		} else {
+			if !errors.Is(err, x.ErrNamespaceNotFound) {
+				glog.Warningf("Error getting namespace ID from name: %v. Defaulting to default or JWT namespace", err)
+			}
+		}
+	}
+	if !attached {
+		ctx = x.AttachJWTNamespace(ctx)
+	}
+	// If acl is enabled, then the namespace from the JWT will be applied in the test below
+	// overriding any namespace from the metadata obtained from the `namespace-str` above.
 	if x.WorkerConfig.AclEnabled && req.GetStartTs() != 0 {
 		// A fresh StartTs is assigned if it is 0.
 		ns, err := x.ExtractNamespace(ctx)

x/x.go

@@ -65,6 +65,8 @@ var (
 	ErrConflict = errors.New("Transaction conflict")
 	// ErrHashMismatch is returned when the hash does not matches the startTs
 	ErrHashMismatch = errors.New("hash mismatch the claimed startTs|namespace")
+	// ErrNamespaceNotFound is returned when a namespace is not found.
+	ErrNamespaceNotFound = errors.New("namespace not found")
 )
 
 const (
@@ -268,6 +270,19 @@ func ExtractNamespace(ctx context.Context) (uint64, error) {
 	return namespace, nil
 }
 
+// ExtractNamespaceStr parses the namespace string value from the incoming gRPC context.
+func ExtractNamespaceStr(ctx context.Context) (string, error) {
+	md, ok := metadata.FromIncomingContext(ctx)
+	if !ok {
+		return "", errors.New("No metadata in the context")
+	}
+	ns := md.Get("namespace-str")
+	if len(ns) == 0 {
+		return "", errors.New("No namespace-str in the metadata of context")
+	}
+	return ns[0], nil
+}
+
 func IsRootNsOperation(ctx context.Context) bool {
 	md, ok := metadata.FromIncomingContext(ctx)
 	if !ok {