Option to use UUIDs instead of integers for node IDs

src/litegraph.js

@@ -142,6 +142,10 @@
 
         ctrl_shift_v_paste_connect_unselected_outputs: false, //[true!] allows ctrl + shift + v to paste nodes with the outputs of the unselected nodes connected with the inputs of the newly pasted nodes
 
+        // if true, all newly created nodes/links will use string UUIDs for their id fields instead of integers.
+        // use this if you must have node IDs that are unique across all graphs and subgraphs.
+        use_uuids: false,
+
         /**
          * Register a node class so it can be listed when the user wants to create a new one
          * @method registerNodeType
@@ -601,6 +605,13 @@
             return target;
         },
 
+        /*
+         * https://gist.github.com/jed/982883?permalink_comment_id=852670#gistcomment-852670
+         */
+        uuidv4: function() {
+            return ([1e7]+-1e3+-4e3+-8e3+-1e11).replace(/[018]/g,a=>(a^Math.random()*16>>a/4).toString(16));
+        },
+
         /**
          * Returns if the types of two slots are compatible (taking into account wildcards, etc)
          * @method isValidConnection
@@ -1405,7 +1416,12 @@
             console.warn(
                 "LiteGraph: there is already a node with this ID, changing it"
             );
-            node.id = ++this.last_node_id;
+            if (LiteGraph.use_uuids) {
+                node.id = LiteGraph.uuidv4();
+            }
+            else {
+                node.id = ++this.last_node_id;
+            }
         }
 
         if (this._nodes.length >= LiteGraph.MAX_NUMBER_OF_NODES) {
@@ -1413,10 +1429,16 @@
         }
 
         //give him an id
-        if (node.id == null || node.id == -1) {
-            node.id = ++this.last_node_id;
-        } else if (this.last_node_id < node.id) {
-            this.last_node_id = node.id;
+        if (LiteGraph.use_uuids) {
+            if (node.id == null || node.id == -1)
+                node.id = LiteGraph.uuidv4();
+        }
+        else {
+            if (node.id == null || node.id == -1) {
+                node.id = ++this.last_node_id;
+            } else if (this.last_node_id < node.id) {
+                this.last_node_id = node.id;
+            }
         }
 
         node.graph = this;
@@ -2412,7 +2434,12 @@
             enumerable: true
         });
 
-        this.id = -1; //not know till not added
+        if (LiteGraph.use_uuids) {
+            this.id = LiteGraph.uuidv4();
+        }
+        else {
+            this.id = -1; //not know till not added
+        }
         this.type = null;
 
         //inputs available: array of inputs
@@ -2626,6 +2653,11 @@
         }
 
         delete data["id"];
+
+        if (LiteGraph.use_uuids) {
+            data["id"] = LiteGraph.uuidv4()
+        }
+
         //remove links
         node.configure(data);
 
@@ -4264,10 +4296,16 @@
                 break;
             }
         }
+
+        var nextId
+        if (LiteGraph.use_uuids)
+            nextId = LiteGraph.uuidv4();
+        else
+            nextId = ++this.graph.last_link_id;
         
 		//create link class
 		link_info = new LLink(
-			++this.graph.last_link_id,
+			nextId,
 			input.type || output.type,
 			this.id,
 			slot,