diff --git a/models/resources/workflow/graph/graph.go b/models/resources/workflow/graph/graph.go
index 316c36d..3635c92 100644
--- a/models/resources/workflow/graph/graph.go
+++ b/models/resources/workflow/graph/graph.go
@@ -3,7 +3,7 @@ package graph
 import "cloud.o-forge.io/core/oc-lib/models/resources"
 
 type Graph struct {
-	Zoom  float64              `bson:"zoom" json:"zoom" validate:"required"`
+	Zoom  float64              `bson:"zoom" json:"zoom" default:"1"`
 	Items map[string]GraphItem `bson:"items" json:"items" default:"{}" validate:"required"`
 	Links []GraphLink          `bson:"links" json:"links" default:"{}" validate:"required"`
 }
@@ -17,22 +17,22 @@ type GraphItem struct {
 }
 
 type GraphLink struct {
-	Source      Position       `bson:"source" json:"source" validate:"required"`
-	Destination Position       `bson:"destination" json:"destination" validate:"required"`
-	Style       GraphLinkStyle `bson:"style" json:"style" validate:"required"`
+	Source      Position        `bson:"source" json:"source" validate:"required"`
+	Destination Position        `bson:"destination" json:"destination" validate:"required"`
+	Style       *GraphLinkStyle `bson:"style,omitempty" json:"style,omitempty"`
 }
 
 type GraphLinkStyle struct {
-	Color           int64    `bson:"color" json:"color" validate:"required"`
-	Stroke          float64  `bson:"stroke" json:"stroke" validate:"required"`
+	Color           int64    `bson:"color" json:"color"`
+	Stroke          float64  `bson:"stroke" json:"stroke"`
 	Tension         float64  `bson:"tension" json:"tension"`
 	HeadRadius      float64  `bson:"head_radius" json:"head_radius"`
 	DashWidth       float64  `bson:"dash_width" json:"dash_width"`
 	DashSpace       float64  `bson:"dash_space" json:"dash_space"`
 	EndArrow        Position `bson:"end_arrow" json:"end_arrow"`
 	StartArrow      Position `bson:"start_arrow" json:"start_arrow"`
-	ArrowStyle      int64    `bson:"arrow_style" json:"arrow_style" validate:"required"`
-	ArrowDirection  int64    `bson:"arrow_direction" json:"arrow_direction" validate:"required"`
+	ArrowStyle      int64    `bson:"arrow_style" json:"arrow_style"`
+	ArrowDirection  int64    `bson:"arrow_direction" json:"arrow_direction"`
 	StartArrowWidth float64  `bson:"start_arrow_width" json:"start_arrow_width"`
 	EndArrowWidth   float64  `bson:"end_arrow_width" json:"end_arrow_width"`
 }
diff --git a/models/workspace/workspace_mongo_accessor.go b/models/workspace/workspace_mongo_accessor.go
index a8bdc96..c735d59 100644
--- a/models/workspace/workspace_mongo_accessor.go
+++ b/models/workspace/workspace_mongo_accessor.go
@@ -1,6 +1,8 @@
 package workspace
 
 import (
+	"errors"
+
 	"cloud.o-forge.io/core/oc-lib/dbs"
 	"cloud.o-forge.io/core/oc-lib/dbs/mongo"
 	"cloud.o-forge.io/core/oc-lib/models/resources/data"
@@ -41,6 +43,11 @@ func (wfa *workspaceMongoAccessor) UpdateOne(set utils.DBObject, id string) (uti
 			}
 		}
 	}
+
+	res, _, err := wfa.Search(nil, set.GetName())
+	if err == nil && len(res) > 0 {
+		return nil, 409, errors.New("A workspace with the same name already exists")
+	}
 	return wfa.GenericUpdateOne(set, id, wfa, &Workspace{})
 }