Merge pull request #3152 from node-red/link-call

Add Link Call node

packages/node_modules/@node-red/editor-client/src/js/nodes.js

@@ -448,12 +448,18 @@ RED.nodes = (function() {
                         doZFilter = true;
                     }
                 }
+                var objectLookup = false;
                 if (searchSet === null) {
-                    searchSet = nodes;
+                    searchSet = Object.keys(nodes);
+                    objectLookup = true;
                 }
 
+
                 for (var n=0;n<searchSet.length;n++) {
                     var node = searchSet[n];
+                    if (objectLookup) {
+                        node = nodes[node];
+                    }
                     if (filter.hasOwnProperty("type") && node.type !== filter.type) {
                         continue;
                     }
@@ -1118,8 +1124,8 @@ RED.nodes = (function() {
                 }
             }
             if ((!n._def.defaults || !n._def.defaults.hasOwnProperty("l")) && n.hasOwnProperty('l')) {
-                var isLink = /^link (in|out)$/.test(node.type);
+                var showLabel = n._def.hasOwnProperty("showLabel")?n._def.showLabel:true;
-                if (isLink == n.l) {
+                if (showLabel != n.l) {
                     node.l = n.l;
                 }
             }

packages/node_modules/@node-red/editor-client/src/js/ui/common/treeList.js

@@ -41,6 +41,7 @@
  *         sublabel: 'Local', // a sub-label for the item
  *         icon: 'fa fa-rocket', // (optional) icon for the item
  *         checkbox: true/false, // (optional) if present, display checkbox accordingly
+ *         radio: 'group-name',  // (optional) if present, display radio box - using group-name to set radio group
  *         selected: true/false, // (optional) whether the item is selected or not
  *         children: [] | function(done,item) // (optional) an array of child items, or a function
  *                                       // that will call the `done` callback with an array
@@ -640,6 +641,41 @@
                     }
                 }
                 selectWrapper.appendTo(label)
+            } else if (item.radio) {
+                var selectWrapper = $('<span class="red-ui-treeList-icon"></span>');
+                var cb = $('<input class="red-ui-treeList-radio" type="radio">').prop('name', item.radio).prop('checked',item.selected).appendTo(selectWrapper);
+                cb.on('click', function(e) {
+                    e.stopPropagation();
+                });
+                cb.on('change', function(e) {
+                    item.selected = this.checked;
+                    that._selected.forEach(function(selectedItem) {
+                        if (selectedItem.radio === item.radio) {
+                            selectedItem.treeList.label.removeClass("selected");
+                            selectedItem.selected = false;
+                            that._selected.delete(selectedItem);
+                        }
+                    })
+                    if (item.selected) {
+                        that._selected.add(item);
+                    } else {
+                        that._selected.delete(item);
+                    }
+                    label.toggleClass("selected",this.checked);
+                    that._trigger("select",e,item);
+                })
+                if (!item.children) {
+                    label.on("click", function(e) {
+                        e.stopPropagation();
+                        cb.trigger("click");
+                    })
+                }
+                item.treeList.select = function(v) {
+                    if (v !== item.selected) {
+                        cb.trigger("click");
+                    }
+                }
+                selectWrapper.appendTo(label)
             } else {
                 label.on("click", function(e) {
                     if (!that.options.multi) {

packages/node_modules/@node-red/editor-client/src/js/ui/editor.js

@@ -151,7 +151,7 @@ RED.editor = (function() {
                 valid = definition[property].hasOwnProperty("required") && !definition[property].required;
             } else {
                 var configNode = RED.nodes.node(value);
-                valid = (configNode !== null && (configNode.valid == null || configNode.valid));
+                valid = (configNode && (configNode.valid == null || configNode.valid));
             }
         }
         return valid;

packages/node_modules/@node-red/editor-client/src/js/ui/editors/panes/appearance.js

@@ -93,17 +93,20 @@
 
 
                 }
+                var showLabel = node._def.hasOwnProperty("showLabel")?node._def.showLabel:true;
+
                 if (!$("#node-input-show-label").prop('checked')) {
                     // Not checked - hide label
-                    if (!/^link (in|out)$/.test(node.type)) {
+
-                        // Not a link node - default state is true
+                    if (showLabel) {
+                        // Default to show label
                         if (node.l !== false) {
                             editState.changes.l = node.l
                             editState.changed = true;
                         }
                         node.l = false;
                     } else {
-                        // A link node - default state is false
+                        // Node has showLabel:false (eg link nodes)
                         if (node.hasOwnProperty('l') && node.l) {
                             editState.changes.l = node.l
                             editState.changed = true;
@@ -112,8 +115,8 @@
                     }
                 } else {
                     // Checked - show label
-                    if (!/^link (in|out)$/.test(node.type)) {
+                    if (showLabel) {
-                        // Not a link node - default state is true
+                        // Default to show label
                         if (node.hasOwnProperty('l') && !node.l) {
                             editState.changes.l = node.l
                             editState.changed = true;
@@ -204,8 +207,8 @@
         })
 
         if (!node.hasOwnProperty("l")) {
-            // Show label if type not link
+            // Show label unless def.showLabel set to false
-            node.l = !/^link (in|out)$/.test(node._def.type);
+            node.l =  node._def.hasOwnProperty("showLabel")?node._def.showLabel:true;
         }
         $("#node-input-show-label").prop("checked",node.l).trigger("change");
 

packages/node_modules/@node-red/editor-client/src/js/ui/view-tools.js

@@ -159,15 +159,15 @@ RED.view.tools = (function() {
         nodes.forEach(function(n) {
             var modified = false;
             var oldValue = n.l === undefined?true:n.l;
-            var isLink = /^link (in|out)$/.test(n._def.type);
+            var showLabel = n._def.hasOwnProperty("showLabel")?n._def.showLabel:true;
 
             if (labelShown) {
-                if (n.l === false || (isLink && !n.hasOwnProperty('l'))) {
+                if (n.l === false || (!showLabel && !n.hasOwnProperty('l'))) {
                     n.l = true;
                     modified = true;
                 }
             } else {
-                if ((!isLink && (!n.hasOwnProperty('l') || n.l === true)) || (isLink && n.l === true) ) {
+                if ((showLabel && (!n.hasOwnProperty('l') || n.l === true)) || (!showLabel && n.l === true) ) {
                     n.l = false;
                     modified = true;
                 }

packages/node_modules/@node-red/editor-client/src/js/ui/view.js

@@ -413,7 +413,7 @@ RED.view = (function() {
                 var nn = result.node;
 
                 var showLabel = RED.utils.getMessageProperty(RED.settings.get('editor'),"view.view-node-show-label");
-                if (showLabel !== undefined && !/^link (in|out)$/.test(nn._def.type) && !nn._def.defaults.hasOwnProperty("l")) {
+                if (showLabel !== undefined &&  (nn._def.hasOwnProperty("showLabel")?nn._def.showLabel:true) && !nn._def.defaults.hasOwnProperty("l")) {
                     nn.l = showLabel;
                 }
 
@@ -1088,7 +1088,7 @@ RED.view = (function() {
                 nn.x = point[0];
                 nn.y = point[1];
                 var showLabel = RED.utils.getMessageProperty(RED.settings.get('editor'),"view.view-node-show-label");
-                if (showLabel !== undefined && !/^link (in|out)$/.test(nn._def.type) && !nn._def.defaults.hasOwnProperty("l")) {
+                if (showLabel !== undefined && (nn._def.hasOwnProperty("showLabel")?nn._def.showLabel:true) && !nn._def.defaults.hasOwnProperty("l")) {
                     nn.l = showLabel;
                 }
                 if (quickAddLink) {
@@ -1991,7 +1991,7 @@ RED.view = (function() {
                 activeLinkNodes = {};
                 for (var i=0;i<movingSet.length();i++) {
                     var msn = movingSet.get(i);
-                    if ((msn.n.type === "link out" || msn.n.type === "link in") &&
+                    if (((msn.n.type === "link out" && msn.n.mode !== 'return') || msn.n.type === "link in") &&
                         (msn.n.z === activeWorkspace)) {
                         var linkNode = msn.n;
                         activeLinkNodes[linkNode.id] = linkNode;
@@ -4140,7 +4140,7 @@ RED.view = (function() {
                         }
                         var numOutputs = d.outputs;
                         if (isLink && d.type === "link out") {
-                            if (showAllLinkPorts===PORT_TYPE_OUTPUT || activeLinkNodes[d.id]) {
+                            if (d.mode !== "return" && (showAllLinkPorts===PORT_TYPE_OUTPUT || activeLinkNodes[d.id])) {
                                 numOutputs = 1;
                             } else {
                                 numOutputs = 0;

packages/node_modules/@node-red/editor-client/src/sass/ui/common/treeList.scss

@@ -95,7 +95,8 @@
         color: $list-item-color;
     }
 
-    input.red-ui-treeList-checkbox {
+    input.red-ui-treeList-checkbox,
+    input.red-ui-treeList-radio {
         margin: 0;
     }
 }

packages/node_modules/@node-red/nodes/core/common/60-link.html

@@ -12,6 +12,26 @@
         <label for="node-input-name"><i class="fa fa-tag"></i> <span data-i18n="common.label.name"></span></label>
         <input type="text" id="node-input-name" data-i18n="[placeholder]common.label.name">
     </div>
+    <div class="form-row">
+        <label for="node-input-mode"><span data-i18n="link.outMode"></span></label>
+        <select id="node-input-mode" style="width: 70%">
+            <option value="link" selected data-i18n="link.sendToAll"></option>
+            <option value="return" data-i18n="link.returnToCaller"></option>
+        </select>
+    </div>
+    <div class="node-input-link-rows" style="position:relative; height: 30px; text-align: right;"><div style="display:inline-block"><input type="text" id="node-input-link-target-filter"></div></div>
+    <div class="form-row node-input-link-row node-input-link-rows"></div>
+</script>
+
+<script type="text/html" data-template-name="link call">
+    <div class="form-row">
+        <label for="node-input-name"><i class="fa fa-tag"></i> <span data-i18n="common.label.name"></span></label>
+        <input type="text" id="node-input-name" data-i18n="[placeholder]common.label.name">
+    </div>
+    <div class="form-row">
+        <label for="node-input-timeout"><span data-i18n="exec.label.timeout"></span></label>
+        <input type="text" id="node-input-timeout" placeholder="30" style="width: 70px; margin-right: 5px;"><span data-i18n="inject.seconds"></span>
+    </div>
     <div style="position:relative; height: 30px; text-align: right;"><div style="display:inline-block"><input type="text" id="node-input-link-target-filter"></div></div>
     <div class="form-row node-input-link-row"></div>
 </script>
@@ -48,7 +68,6 @@
                 }
             });
         var candidateNodes = RED.nodes.filterNodes({type:targetType});
-
         var search = $("#node-input-link-target-filter").searchBox({
             style: "compact",
             delay: 300,
@@ -104,7 +123,8 @@
                     node: n,
                     label: n.name||n.id,
                     selected: isChecked,
-                    checkbox: true
+                    checkbox: node.type !== "link call",
+                    radio: node.type === "link call"
                 })
             }
         });
@@ -129,15 +149,22 @@
     function onEditSave(node) {
         var flows = treeList.treeList('data');
         node.links = [];
-        flows.forEach(function(f) {
+        if (node.type !== "link out" || $("node-input-mode").val() === 'link') {
-            f.children.forEach(function(n) {
+            flows.forEach(function(f) {
-                if (n.selected) {
+                f.children.forEach(function(n) {
-                    node.links.push(n.id);
+                    if (n.selected) {
-                }
+                        node.links.push(n.id);
+                    }
+                })
             })
-        })
+        }
         node.oldLinks.sort();
         node.links.sort();
+
+        if (node.type === "link call") {
+            return
+        }
+
         var nodeMap = {};
         var length = Math.max(node.oldLinks.length,node.links.length);
         for (var i=0;i<length;i++) {
@@ -195,6 +222,7 @@
         outputLabels: function(i) {
             return this.name||this._("link.linkIn");
         },
+        showLabel: false,
         label: function() {
             return this.name||this._("link.linkIn");
         },
@@ -211,25 +239,32 @@
         oneditresize: resizeNodeList
     });
 
-    RED.nodes.registerType('link out',{
+    RED.nodes.registerType('link call',{
         category: 'common',
         color:"#ddd",//"#87D8CF",
         defaults: {
             name: {value:""},
-            links: { value: [], type:"link in[]"}
+            links: { value: [], type:"link in[]"},
+            timeout: { value: "30", validate:RED.validators.number(true) }
         },
-        align:"right",
+        inputs: 1,
-        inputs:1,
+        outputs: 1,
-        outputs:0,
+        icon: "link-call.svg",
-        icon: "link-out.svg",
         inputLabels: function(i) {
-            return this.name||this._("link.linkOut");
+            return this.name||this._("link.linkCall");
         },
         label: function() {
-            return this.name||this._("link.linkOut");
+            if (this.name) {
+                return this.name;
+            }
+            if (this.links.length > 0) {
+                var targetNode = RED.nodes.node(this.links[0]);
+                return targetNode && (targetNode.name || targetNode.id);
+            }
+            return this._("link.linkCall");
         },
         labelStyle: function() {
-            return this.name?"node_label_italic":"";
+            return (this.name || this.links.length > 0)?"node_label_italic":"";
         },
         oneditprepare: function() {
             onEditPrepare(this,"link in");
@@ -237,8 +272,56 @@
         oneditsave: function() {
             onEditSave(this);
         },
+        oneditresize: resizeNodeList
+    });
+
+
+    RED.nodes.registerType('link out',{
+        category: 'common',
+        color:"#ddd",//"#87D8CF",
+        defaults: {
+            name: {value:""},
+            mode: { value: "link" },// link || return
+            links: { value: [], type:"link in[]"}
+        },
+        align:"right",
+        inputs:1,
+        outputs:0,
+        icon: function() {
+            if (this.mode === "return") {
+                return "link-return.svg";
+            } else {
+                return "link-out.svg";
+            }
+        },
+        inputLabels: function(i) {
+            return this.name||(this.mode === "return" ?this._("link.linkOutReturn"):this._("link.linkOut"));
+        },
+        showLabel: false,
+        label: function() {
+            return this.name||(this.mode === "return" ?this._("link.linkOutReturn"):this._("link.linkOut"));
+        },
+        labelStyle: function() {
+            return this.name?"node_label_italic":"";
+        },
+        oneditprepare: function() {
+            onEditPrepare(this,"link in");
+            $("#node-input-mode").on("change", function() {
+                $(".node-input-link-rows").toggle(this.value === "link")
+            })
+            if (!this.mode) {
+                $("#node-input-mode").val('link').trigger("change");
+            }
+
+        },
+        oneditsave: function() {
+            onEditSave(this);
+        },
         onadd: onAdd,
         oneditresize: resizeNodeList
     });
+
+
+
 })();
 </script>

packages/node_modules/@node-red/nodes/core/common/60-link.js

@@ -17,6 +17,8 @@
 module.exports = function(RED) {
     "use strict";
 
+    const crypto = require("crypto");
+
     function LinkInNode(n) {
         RED.nodes.createNode(this,n);
         var node = this;
@@ -40,13 +42,91 @@ module.exports = function(RED) {
     function LinkOutNode(n) {
         RED.nodes.createNode(this,n);
         var node = this;
+        var mode = n.mode || "link";
+
         var event = "node:"+n.id;
         this.on("input", function(msg, send, done) {
             msg._event = event;
             RED.events.emit(event,msg)
-            send(msg);
+
-            done();
+            if (mode === "return") {
+                if (Array.isArray(msg._linkSource) && msg._linkSource.length > 0) {
+                    var messageEvent = msg._linkSource.pop();
+                    var returnNode = RED.nodes.getNode(messageEvent.node);
+                    if (returnNode && returnNode.returnLinkMessage) {
+                        returnNode.returnLinkMessage(messageEvent.id, msg);
+                    } else {
+                        node.warn(RED._("link.error.missingReturn"))
+                    }
+                } else {
+                    node.warn(RED._("link.error.missingReturn"))
+                }
+                done();
+            } else if (mode === "link") {
+                send(msg);
+                done();
+            }
         });
     }
     RED.nodes.registerType("link out",LinkOutNode);
+
+
+    function LinkCallNode(n) {
+        RED.nodes.createNode(this,n);
+        const node = this;
+        const target = n.links[0];
+        const messageEvents = {};
+        let timeout = parseFloat(n.timeout || "30")*1000;
+        if (isNaN(timeout)) {
+            timeout = 30000;
+        }
+
+        this.on("input", function(msg, send, done) {
+            msg._linkSource = msg._linkSource || [];
+            const messageEvent = {
+                id: crypto.randomBytes(14).toString('hex'),
+                node: node.id,
+            }
+            messageEvents[messageEvent.id] = {
+                msg: RED.util.cloneMessage(msg),
+                send,
+                done,
+                ts: setTimeout(function() {
+                    timeoutMessage(messageEvent.id)
+                }, timeout )
+            };
+            msg._linkSource.push(messageEvent);
+            var targetNode = RED.nodes.getNode(target);
+            if (targetNode) {
+                targetNode.receive(msg);
+            }
+        });
+
+        this.returnLinkMessage = function(eventId, msg) {
+            if (Array.isArray(msg._linkSource) && msg._linkSource.length === 0) {
+                delete msg._linkSource;
+            }
+            const messageEvent = messageEvents[eventId];
+            if (messageEvent) {
+                clearTimeout(messageEvent.ts);
+                delete messageEvents[eventId];
+                messageEvent.send(msg);
+                messageEvent.done();
+            } else {
+                node.send(msg);
+            }
+        }
+
+        function timeoutMessage(eventId) {
+            const messageEvent = messageEvents[eventId];
+            if (messageEvent) {
+                delete messageEvents[eventId];
+                node.error("timeout",messageEvent.msg);
+            }
+        }
+
+    }
+    RED.nodes.registerType("link call",LinkCallNode);
+
+
 }

packages/node_modules/@node-red/nodes/icons/link-call.svg

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+<svg width="10.583mm" height="15.875mm" version="1.1" viewBox="0 0 10.583 15.875" xmlns="http://www.w3.org/2000/svg">
+ <path d="m8.2021 2.3812-4.8922 0.53612 1.604 0.92604-1.0395 1.8004c0.73719-0.37402 1.6437-0.38227 2.4095 0.059892 0.76511 0.44174 1.2118 1.2301 1.2577 2.055l1.0384-1.7986 1.604 0.92604zm-2.3813 4.1244c-0.77016-0.44465-1.7402-0.18474-2.1848 0.58542-0.44465 0.77016-0.185 1.7406 0.58516 2.1853 0.77016 0.44465 1.7422 0.18533 2.1869-0.58483 0.44465-0.77016 0.18295-1.7412-0.58721-2.1858zm-3.3193 1.5159-1.8211 3.1542 3.6662 2.1167 1.82-3.1524c-0.73731 0.37266-1.6431 0.37961-2.4082-0.062129-0.76585-0.44216-1.2122-1.2309-1.2569-2.0563z" fill="#fff"/>
+</svg>

packages/node_modules/@node-red/nodes/icons/link-return.svg

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+<svg width="10.583mm" height="15.875mm" version="1.1" viewBox="0 0 10.583 15.875" xmlns="http://www.w3.org/2000/svg">
+ <path d="m2.6623 13.292 4.8922-0.53612-1.604-0.92604 1.0395-1.8004c-0.73719 0.37402-1.6437 0.38227-2.4095-0.059892-0.76511-0.44174-1.2118-1.2301-1.2577-2.055l-1.0384 1.7986-1.604-0.92604zm2.3813-4.1244c0.77016 0.44465 1.7402 0.18474 2.1848-0.58542 0.44465-0.77016 0.185-1.7406-0.58516-2.1853-0.77016-0.44465-1.7422-0.18533-2.1869 0.58483-0.44465 0.77016-0.18295 1.7412 0.58721 2.1858zm3.3193-1.5159 1.8211-3.1542-3.6662-2.1167-1.82 3.1524c0.73731-0.37266 1.6431-0.37961 2.4082 0.062129 0.76585 0.44216 1.2122 1.2309 1.2569 2.0563z" fill="#fff"/>
+</svg>

packages/node_modules/@node-red/nodes/locales/en-US/common/60-link.html

@@ -28,10 +28,23 @@
 <script type="text/html" data-help-name="link out">
     <p>Create virtual wires between flows.</p>
     <h3>Details</h3>
-    <p>The node can be connected to any <code>link in</code> node that exists on any tab.
+    <p>This node can be configured to either send messages to all <code>link in</code>
-       Once connected, they behave as if they were wired together.</p>
+        nodes it is connected to, or to send a response back to the <code>link call</code>
-    <p>The wires between link nodes are only displayed when a link node is selected.
+        node that triggered the flow.</p>
-       If there are any wires to other tabs, a virtual node is show that can be clicked
+    <p>When in 'send to all' mode, the wires between link nodes are only displayed when
-       on to jump to the appropriate tab.</p>
+       the node is selected. If there are any wires to other tabs, a virtual node
+       is shown that can be clicked on to jump to the appropriate tab.</p>
     <p><b>Note: </b>Links cannot be created going into, or out of, a subflow.</p>
 </script>
+
+<script type="text/html" data-help-name="link call">
+    <p>Calls a flow that starts with a <code>link in</code> node and passes on the response.</p>
+    <h3>Details</h3>
+    <p>This node can be connected to a <code>link in</code> node that exists on any tab.
+       The flow connected to that node must end with a <code>link out</code> node configured
+       in 'return' mode.</p>
+    <p>When this node receives a message, it is passed to the connected <code>link in</code> node.
+       It then waits for a response which it then sends on.</o>
+    <p>If no response is received within the configured timeout, default 30 seconds, the node
+       will log an error that can be caught using the <code>catch</code> node.</p>
+</script>

packages/node_modules/@node-red/nodes/locales/en-US/messages.json

@@ -159,7 +159,15 @@
     },
     "link": {
         "linkIn": "link in",
-        "linkOut": "link out"
+        "linkOut": "link out",
+        "linkCall": "link call",
+        "linkOutReturn": "link return",
+        "outMode": "Mode",
+        "sendToAll": "Send to all connected link nodes",
+        "returnToCaller": "Return to calling link node",
+        "error": {
+            "missingReturn": "Missing return node information"
+        }
     },
     "tls": {
         "tls": "TLS configuration",

test/nodes/core/common/60-link_spec.js

@@ -119,4 +119,69 @@ describe('link Node', function() {
         });
     });
 
+    describe("link-call node", function() {
+        it('should call link-in node and get response', function(done) {
+            var flow = [{id:"link-in-1", type:"link in", wires: [[ "func"]]},
+                        {id:"func", type:"helper", wires: [["link-out-1"]]},
+                        {id:"link-out-1", type:"link out", mode: "return"},
+                        {id:"link-call", type:"link call", links:["link-in-1"], wires:[["n4"]]},
+                        {id:"n4", type:"helper"} ];
+            helper.load(linkNode, flow, function() {
+                var func = helper.getNode("func");
+                func.on("input", function(msg, send, done) {
+                    msg.payload = "123";
+                    send(msg);
+                    done();
+                })
+                var n1 = helper.getNode("link-call");
+                var n4 = helper.getNode("n4");
+                n4.on("input", function(msg) {
+                    try {
+                        msg.should.have.property('payload', '123');
+                        done();
+                    } catch(err) {
+                        done(err);
+                    }
+                });
+                n1.receive({payload:"hello"});
+            });
+        })
+    });
+
+    it('should allow nested link-call flows', function(done) {
+        var flow = [/** Multiply by 2 link flow **/
+                    {id:"li1", type:"link in", wires: [[ "m2"]]},
+                    {id:"m2", type:"helper", wires: [["lo1"]]},
+                    {id:"lo1", type:"link out", mode: "return"},
+                    /** Multiply by 3 link flow **/
+                    {id:"li2", type:"link in", wires: [[ "m3"]]},
+                    {id:"m3", type:"helper", wires: [["lo2"]]},
+                    {id:"lo2", type:"link out", mode: "return"},
+                    /** Multiply by 6 link flow **/
+                    {id:"li3", type:"link in", wires: [[ "link-call-1"]]},
+                    {id:"link-call-1", type:"link call", links:["m2"], wires:[["link-call-2"]]},
+                    {id:"link-call-2", type:"link call", links:["m3"], wires:[["lo3"]]},
+                    {id:"lo3", type:"link out", mode: "return"},
+                    /** Test Flow Entry **/
+                    {id:"link-call", type:"link call", links:["li3"], wires:[["n4"]]},
+                    {id:"n4", type:"helper"} ];
+        helper.load(linkNode, flow, function() {
+            var m2 = helper.getNode("m2");
+            m2.on("input", function(msg, send, done) { msg.payload *= 2 ; send(msg); done(); })
+            var m3 = helper.getNode("m3");
+            m3.on("input", function(msg, send, done) { msg.payload *= 3 ; send(msg); done(); })
+
+            var n1 = helper.getNode("link-call");
+            var n4 = helper.getNode("n4");
+            n4.on("input", function(msg) {
+                try {
+                    msg.should.have.property('payload', 24);
+                    done();
+                } catch(err) {
+                    done(err);
+                }
+            });
+            n1.receive({payload:4});
+        });
+    })
 });