# Please help me with creating a simple generator counter

**URL:** <https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117>\
**Category:** General\
**Tags:** function-node\
**Created:** [4 March 2023 20:18 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117 "2023-03-04T20:18:14Z")\
**Posts on this page:** 17\
**Page:** 1

<div class="post-metadata">

**Author:** ![alexsahka](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/alexsahka/32/7897_2.png) [@alexsahka](https://discourse.nodered.org/u/alexsahka)\
**Post date:** [4 March 2023 20:18 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/1 "2023-03-04T20:18:14Z")

</div>

Could someone help me with creating a simple generator counter, only using the JavaScript function node without using context storage?  
Here is the prototype, but I can't use it in my application because it uses an additional trigger node

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/5/3527cc9c945dbaa8f988bcf1c7edc3bbca538704.png)

```auto
[{"id":"99785fc8.6687a","type":"inject","z":"15cf35e317766a1e","name":"trigger to start","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":"","topic":"","payload":"0","payloadType":"str","x":1550,"y":1940,"wires":[["9bc2c452.643d38"]]},{"id":"5cbf5a97.a340a4","type":"debug","z":"15cf35e317766a1e","name":"","active":true,"console":false,"complete":false,"x":1910,"y":1940,"wires":[]},{"id":"1ab3bd1e42e54874","type":"inject","z":"15cf35e317766a1e","name":"trigger to stop","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"stop","payloadType":"str","x":1550,"y":2000,"wires":[["28e99bac12b0ed7b"]]},{"id":"2ec4101beac37945","type":"group","z":"15cf35e317766a1e","style":{"stroke":"#999999","stroke-opacity":"1","fill":"none","fill-opacity":"1","label":true,"label-position":"nw","color":"#a4a4a4"},"nodes":["9bc2c452.643d38","28e99bac12b0ed7b"],"x":1634,"y":1901,"w":173,"h":140},{"id":"9bc2c452.643d38","type":"function","z":"15cf35e317766a1e","g":"2ec4101beac37945","name":"counter","func":"msg.payload = parseInt(msg.payload) + 1;\n\n\nreturn msg;","outputs":"1","noerr":0,"initialize":"","finalize":"","libs":[],"x":1721,"y":1942,"wires":[["5cbf5a97.a340a4","28e99bac12b0ed7b"]]},{"id":"28e99bac12b0ed7b","type":"trigger","z":"15cf35e317766a1e","g":"2ec4101beac37945","name":"","op1":"","op2":"","op1type":"nul","op2type":"payl","duration":"1","extend":false,"overrideDelay":false,"units":"s","reset":"stop","bytopic":"all","topic":"topic","outputs":1,"x":1720,"y":2000,"wires":[["9bc2c452.643d38"]]}]

```

---

<div class="post-metadata">

**Author:** ![Paul-Reed](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/paul-reed/32/66906_2.png) [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)\
**Post date:** [4 March 2023 21:11 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/2 "2023-03-04T21:11:50Z")

</div>

> [@alexsahka](#):
>
> only using the JavaScript function node without using context storage?

Could I ask why you are averse to using context storage?

---

<div class="post-metadata">

**Author:** ![Colin](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/colin/32/17040_2.png) [@Colin](https://discourse.nodered.org/u/Colin)\
**Post date:** [4 March 2023 21:20 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/3 "2023-03-04T21:20:55Z")

</div>

You can use the javascript timer function setInterval() to do that.

---

<div class="post-metadata">

**Author:** ![alexsahka](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/alexsahka/32/7897_2.png) [@alexsahka](https://discourse.nodered.org/u/alexsahka)\
**Post date:** [4 March 2023 21:25 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/4 "2023-03-04T21:25:39Z")

</div>

This will be used inside the node-red-contrib-hal2 node as a script, but multiple times (similar to template usage)

---

<div class="post-metadata">

**Author:** ![Paul-Reed](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/paul-reed/32/66906_2.png) [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)\
**Post date:** [4 March 2023 21:45 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/5 "2023-03-04T21:45:25Z")

</div>

> [@alexsahka](#):
>
> This will be used inside the node-red-contrib-hal2 node as a script

Contrib nodes can store data within their own context object, and as far as I can recall would be stored in the scope of each node, but I'm sure you will have already considered that option.

---

<div class="post-metadata">

**Author:** ![alexsahka](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/alexsahka/32/7897_2.png) [@alexsahka](https://discourse.nodered.org/u/alexsahka)\
**Post date:** [6 March 2023 22:46 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/7 "2023-03-06T22:46:29Z")

</div>

Here is my flow:

```auto
[{"id":"9ff1d0c1701d7a88","type":"inject","z":"15cf35e317766a1e","name":"","props":[{"p":"payload"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"start","payloadType":"str","x":1150,"y":340,"wires":[["595eb2d2d60ffe40"]]},{"id":"3984225bc1c55359","type":"debug","z":"15cf35e317766a1e","name":"debug 152","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":1530,"y":340,"wires":[]},{"id":"595eb2d2d60ffe40","type":"function","z":"15cf35e317766a1e","name":"function 7","func":"var counter = 0;\nvar interval;\nvar running = false;\n\nfunction startCounter() {\n if (!running) {\n running = true;\n interval = setInterval(function () {\n counter++;\n if (counter <= 9) {\n node.send({ payload: counter });\n } else {\n stopCounter();\n }\n }, 1000);\n }\n}\n\nfunction stopCounter() {\n if (running) {\n clearInterval(interval);\n running = false;\n }\n}\n\nif (msg.payload === 'start') {\n startCounter();\n} else if (msg.payload === 'stop') {\n stopCounter();\n} else {\n node.error('Invalid input. Must be \"start\" or \"stop\".');\n}\n","outputs":1,"noerr":0,"initialize":"","finalize":"","libs":[],"x":1340,"y":340,"wires":[["3984225bc1c55359"]]},{"id":"b22bfaaa6840af24","type":"inject","z":"15cf35e317766a1e","name":"","props":[{"p":"payload"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"error","payloadType":"str","x":1150,"y":420,"wires":[["595eb2d2d60ffe40"]]},{"id":"5b4ee0997e709bcf","type":"inject","z":"15cf35e317766a1e","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"stop","payloadType":"str","x":1150,"y":380,"wires":[["595eb2d2d60ffe40"]]}]

```

One problem stop "button" wont stop the count, and the multi-click of the start "button" creates a multi-count instead of ignoring or starting from zero.

```auto
var counter = 0;
var interval;
var running = false;

function startCounter() {
    if (!running) {
        running = true;
        interval = setInterval(function () {
            counter++;
            if (counter <= 9) {
                node.send({ payload: counter });
            } else {
                stopCounter();
            }
        }, 1000);
    }
}

function stopCounter() {
    if (running) {
        clearInterval(interval);
        running = false;
    }
}

if (msg.payload === 'start') {
    startCounter();
} else if (msg.payload === 'stop') {
    stopCounter();
} else {
    node.error('Invalid input. Must be "start" or "stop".');
}

```

![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/5/2/5225cf074a8dc026e395fc67f322c8ab9113b542.png)

---

<div class="post-metadata">

**Author:** ![Frida](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/frida/32/68250_2.png) [@Frida](https://discourse.nodered.org/u/Frida)\
**Post date:** [7 March 2023 07:37 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/8 "2023-03-07T07:37:16Z")

</div>

Try this.

```auto
[
    {
        "id": "98726f178094f33b",
        "type": "tab",
        "label": "Flow 2",
        "disabled": false,
        "info": "",
        "env": []
    },
    {
        "id": "9ff1d0c1701d7a88",
        "type": "inject",
        "z": "98726f178094f33b",
        "name": "",
        "props": [
            {
                "p": "payload"
            }
        ],
        "repeat": "",
        "crontab": "",
        "once": false,
        "onceDelay": 0.1,
        "topic": "",
        "payload": "start",
        "payloadType": "str",
        "x": 190,
        "y": 160,
        "wires": [
            [
                "595eb2d2d60ffe40"
            ]
        ]
    },
    {
        "id": "3984225bc1c55359",
        "type": "debug",
        "z": "98726f178094f33b",
        "name": "debug 152",
        "active": true,
        "tosidebar": true,
        "console": false,
        "tostatus": false,
        "complete": "payload",
        "targetType": "msg",
        "statusVal": "",
        "statusType": "auto",
        "x": 570,
        "y": 160,
        "wires": []
    },
    {
        "id": "595eb2d2d60ffe40",
        "type": "function",
        "z": "98726f178094f33b",
        "name": "function 7",
        "func": "var counter = 0;\nlet intervalID = context.get('intervalID') ?? undefined\n\n\nfunction startCounter() {\n if (intervalID != undefined) { clearInterval(intervalID) }\n intervalID = setInterval(function () {\n counter++;\n if (counter <= 9) {\n node.send({ payload: counter });\n } else {\n stopCounter();\n }\n }, 1000);\n \n}\n\n\nfunction stopCounter() {\n clearInterval(intervalID);\n}\n\n\nif (msg.payload === 'start') {\n startCounter();\n} else if (msg.payload === 'stop') {\n stopCounter()\n} else {\n node.error('Invalid input. Must be \"start\" or \"stop\".');\n}\n\n\ncontext.set('intervalID', intervalID)\n",
        "outputs": 1,
        "noerr": 0,
        "initialize": "",
        "finalize": "",
        "libs": [],
        "x": 380,
        "y": 160,
        "wires": [
            [
                "3984225bc1c55359"
            ]
        ]
    },
    {
        "id": "b22bfaaa6840af24",
        "type": "inject",
        "z": "98726f178094f33b",
        "name": "",
        "props": [
            {
                "p": "payload"
            }
        ],
        "repeat": "",
        "crontab": "",
        "once": false,
        "onceDelay": 0.1,
        "topic": "",
        "payload": "error",
        "payloadType": "str",
        "x": 190,
        "y": 240,
        "wires": [
            [
                "595eb2d2d60ffe40"
            ]
        ]
    },
    {
        "id": "5b4ee0997e709bcf",
        "type": "inject",
        "z": "98726f178094f33b",
        "name": "",
        "props": [
            {
                "p": "payload"
            },
            {
                "p": "topic",
                "vt": "str"
            }
        ],
        "repeat": "",
        "crontab": "",
        "once": false,
        "onceDelay": 0.1,
        "topic": "",
        "payload": "stop",
        "payloadType": "str",
        "x": 190,
        "y": 200,
        "wires": [
            [
                "595eb2d2d60ffe40"
            ]
        ]
    }
]

```

PS. You can't do it without using context storage.

---

<div class="post-metadata">

**Author:** ![alexsahka](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/alexsahka/32/7897_2.png) [@alexsahka](https://discourse.nodered.org/u/alexsahka)\
**Post date:** [7 March 2023 08:35 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/9 "2023-03-07T08:35:58Z")

</div>

> [@Frida](#):
>
> PS. You can't do it without using context storage.

I need to use this counting script in the node-red-contrib-hal2 and usage context storage interferes somehow.

Thanks for cleaning up the code.

---

<div class="post-metadata">

**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [7 March 2023 08:44 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/10 "2023-03-07T08:44:14Z")

</div>

It's always a good idea to check the node's gitHub page to see your issue matches someone else's. You might want to see if this helps:

> <https://github.com/flic/node-red-contrib-hal2/issues/26>
>
> Home assistant NodeRed addon memory only in Context store no file option.
> 
> !\[i…mage\](https://user-images.githubusercontent.com/7469537/188496321-4a8ac1b6-87a9-4aaa-93cb-c106e2b965eb.png)
> 
> NodeRed : 
> !\[image\](https://user-images.githubusercontent.com/7469537/188496400-e760d505-2ed9-4b67-b275-309a23e5078e.png)
> 
> Hal2: 
> !\[image\](https://user-images.githubusercontent.com/7469537/188496459-8c3307be-990e-4580-8373-3db244a39e02.png)

---

<div class="post-metadata">

**Author:** ![alexsahka](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/alexsahka/32/7897_2.png) [@alexsahka](https://discourse.nodered.org/u/alexsahka)\
**Post date:** [7 March 2023 15:57 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/11 "2023-03-07T15:57:48Z")

</div>

It's me who opened this issue here: [Home assistant NodeRed addon memory only in Context store · Issue #26 · flic/node-red-contrib-hal2 · GitHub](https://github.com/flic/node-red-contrib-hal2/issues/26)

But the essence of the problem is quite different. And I find out that the problem is not with the node-red-contrib-hal2 node, but with my NodeRed settings.

---

<div class="post-metadata">

**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [7 March 2023 16:13 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/12 "2023-03-07T16:13:45Z")

</div>

> [@alexsahka](#):
>
> But the essence of the problem is quite different. And I find out that the problem is not with the node-red-contrib-hal2 node, but with my NodeRed settings.

Does this mean you have solved your issue? If not what do you mean my your `NodeRed settings` what you have in settings.js?

---

<div class="post-metadata">

**Author:** ![alexsahka](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/alexsahka/32/7897_2.png) [@alexsahka](https://discourse.nodered.org/u/alexsahka)\
**Post date:** [7 March 2023 19:51 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/13 "2023-03-07T19:51:10Z")

</div>

These are two completely different questions/issues.

---

<div class="post-metadata">

**Author:** ![zenofmud](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/zenofmud/32/316_2.png) [@zenofmud](https://discourse.nodered.org/u/zenofmud)\
**Post date:** [7 March 2023 20:08 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/14 "2023-03-07T20:08:44Z")

</div>

> [@zenofmud](#):
>
> If not what do you mean my your `NodeRed settings` what you have in settings.js?

So are you going to answer my question?

---

<div class="post-metadata">

**Author:** ![alexsahka](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/alexsahka/32/7897_2.png) [@alexsahka](https://discourse.nodered.org/u/alexsahka)\
**Post date:** [7 March 2023 20:20 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/15 "2023-03-07T20:20:23Z")

</div>

Solved this by enabling "Saving context data to the file-system" this is disabled in settings.js by default:  
[https://nodered.org/docs/user-guide/context](https://nodered.org/docs/user-guide/context)

Saving context data to the file-system  
To enable file-based storage, the following option can be used:

contextStorage: {  
default: {  
module: "localfilesystem"  
}  
}

---

<div class="post-metadata">

**Author:** ![Paul-Reed](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/paul-reed/32/66906_2.png) [@Paul-Reed](https://discourse.nodered.org/u/Paul-Reed)\
**Post date:** [7 March 2023 21:52 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/16 "2023-03-07T21:52:11Z")

</div>

> [@alexsahka](#):
>
> Solved this by enabling "Saving context data to the file-system" this is disabled in settings.js by default:

So if this 'solution' is to be used in a contrib node, do you expect all users of the node to edit their `settings.js` file?

---

<div class="post-metadata">

**Author:** ![alexsahka](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/alexsahka/32/7897_2.png) [@alexsahka](https://discourse.nodered.org/u/alexsahka)\
**Post date:** [8 March 2023 00:17 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/17 "2023-03-08T00:17:19Z")

</div>

> [@Paul-Reed](#):
>
> So if this 'solution' is to be used in a contrib node, do you expect all users of the node to edit their `settings.js` file?

I think this is clear from the Node-red user guide: [Working with context : Node-RED](https://nodered.org/docs/user-guide/context)  
If the user wants to save any node data to localfilesystem

#### Saving context data to the file-system

To enable file-based storage, the following option can be used:

```auto
contextStorage: {
   default: {
       module: "localfilesystem"
   }
}

```

This sets the default context store to be an instance of the `localfilesystem` plugin, with all of its default settings. That means:

- it will store the context data in files under `~/.node-red/context/`
- it caches the values in memory and only writes them out to the file-system every 30 seconds.

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\
**Post date:** [7 May 2023 00:17 UTC](https://discourse.nodered.org/t/please-help-me-with-creating-a-simple-generator-counter/76117/18 "2023-05-07T00:17:27Z")

</div>

This topic was automatically closed 60 days after the last reply. New replies are no longer allowed.