dgbuilder/core_nodes/core/80-function.js

   1 /**
   2  * Copyright 2013 IBM Corp.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  **/
  16
  17 module.exports = function(RED) {
  18     "use strict";
  19     var util = require("util");
  20     var vm = require("vm");
  21
  22     function FunctionNode(n) {
  23         RED.nodes.createNode(this,n);
  24         this.name = n.name;
  25         this.func = n.func;
  26         var functionText = "var results = null; results = (function(msg){"+this.func+"\n})(msg);";
  27         this.topic = n.topic;
  28         var sandbox = {
  29             console:console,
  30             util:util,
  31             Buffer:Buffer,
  32             context: {
  33                 global:RED.settings.functionGlobalContext || {}
  34             }
  35         };
  36         var context = vm.createContext(sandbox);
  37         try {
  38             this.script = vm.createScript(functionText);
  39             this.on("input", function(msg) {
  40                 try {
  41                     var start = process.hrtime();
  42                     context.msg = msg;
  43                     this.script.runInContext(context);
  44                     var results = context.results;
  45                     if (results == null) {
  46                         results = [];
  47                     } else if (results.length == null) {
  48                         results = [results];
  49                     }
  50                     if (msg._topic) {
  51                         for (var m in results) {
  52                             if (results[m]) {
  53                                 if (util.isArray(results[m])) {
  54                                     for (var n=0; n < results[m].length; n++) {
  55                                         results[m][n]._topic = msg._topic;
  56                                     }
  57                                 } else {
  58                                     results[m]._topic = msg._topic;
  59                                 }
  60                             }
  61                         }
  62                     }
  63                     this.send(results);
  64                     var duration = process.hrtime(start);
  65                     if (process.env.NODE_RED_FUNCTION_TIME) {
  66                         this.status({fill:"yellow",shape:"dot",text:""+Math.floor((duration[0]* 1e9 +  duration[1])/10000)/100});
  67                     }
  68                 } catch(err) {
  69                     this.error(err.toString());
  70                 }
  71             });
  72         } catch(err) {
  73             this.error(err);
  74         }
  75     }
  76
  77     RED.nodes.registerType("function",FunctionNode);
  78     RED.library.register("functions");
  79 }