Add change node to core/logic - allows simple(r) manipulation of some payloads and msg.properties to save having to write functions for these basic tasks. You can replace contents (regex based or simple swap), and add, modify or delete proerties.

nodes/core/logic/15-change.js

@@ -0,0 +1,66 @@
+/**
+ * Copyright 2013 IBM Corp.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ **/
+
+var RED = require(process.env.NODE_RED_HOME + "/red/red");
+
+function ChangeNode(n) {
+    RED.nodes.createNode(this, n);
+    this.action = n.action;
+    this.property = n.property || "";
+    this.from = n.from || " ";
+    this.to = n.to || " ";
+    var node = this;
+
+    var makeNew = function( stem, path, value ) {
+        var lastPart = (arguments.length === 3) ? path.pop() : false;
+        for (var i = 0; i < path.length; i++) {
+            stem = stem[path[i]] = stem[path[i]] || {};
+        }
+        if (lastPart) { stem = stem[lastPart] = value; }
+        return stem;
+    };
+
+    this.on('input', function (msg) {
+        if (node.action == "change") {
+            node.re = new RegExp(this.from, "g");
+            if (typeof msg[node.property] === "string") {
+                msg[node.property] = (msg[node.property]).replace(node.re, node.to);
+            }
+        }
+        //else if (node.action == "replace") {
+            //if (node.to.indexOf("msg.") == 0) {
+                //msg[node.property] = eval(node.to);
+            //}
+            //else {
+                //msg[node.property] = node.to;
+            //}
+        //}
+        else if (node.action == "replace") {
+            if (node.to.indexOf("msg.") == 0) {
+                makeNew( msg, node.property.split("."), eval(node.to) );
+            }
+            else {
+                makeNew( msg, node.property.split("."), node.to );
+            }
+            //makeNew( msg, node.property.split("."), node.to );
+        }
+        else if (node.action == "delete") {
+            delete(msg[node.property]);
+        }
+        node.send(msg);
+    });
+}
+RED.nodes.registerType("change", ChangeNode);