Fixed node color issues

editor/js/graph.js

@@ -87,16 +87,17 @@ export class Graph extends ManagedData {
     }
 
     getNodeColor(node) {
-        return node.type.color;
+        if (node === undefined || node.type === undefined) {
+            return "black";
+        }
+        return "#" + node.type.color;
     }
 
     calculateNodeTypes() {
         // TODO: Collect all types from database
         const nodeClasses = [];
 
-        this.data.nodes.forEach((node) =>
-            nodeClasses.push(node[NODE_TYPE])
-        );
+        this.data.nodes.forEach((node) => nodeClasses.push(node[NODE_TYPE]));
 
         this.nodeTypes = [...new Set(nodeClasses)];
     }

editor/js/state.js

@@ -266,11 +266,11 @@ export class State extends Tool {
         // Color at source node referencing the target node and vice versa
         gradient.addColorStop(
             "0",
-            "#" + graph.getNodeColor(link[Graph.LINK_TARGET_OBJ])
+            graph.getNodeColor(link[Graph.LINK_TARGET_OBJ])
         );
         gradient.addColorStop(
             "1",
-            "#" + graph.getNodeColor(link[Graph.LINK_SOURCE_OBJ])
+            graph.getNodeColor(link[Graph.LINK_SOURCE_OBJ])
         );
 
         ctx.beginPath();