# Need help with this error

**URL:** <https://discourse.nodered.org/t/need-help-with-this-error/67953>\
**Category:** General\
**Created:** [20 September 2022 01:00 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953 "2022-09-20T01:00:24Z")\
**Posts on this page:** 18\
**Page:** 1

<div class="post-metadata">

**Author:** ![Trying\_to\_learn](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/trying_to_learn/32/28400_2.png) [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Post date:** [20 September 2022 01:00 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/1 "2022-09-20T01:00:24Z")

</div>

I am seeing this error:

```auto
{"_msgid":"772966b40bfa3282","_event":"node:eafdfa87.79d67","error":{"message":"TypeError: Cannot read property 'colour' of undefined","source":{"id":"fed40e07.141c68","type":"function","name":"Ack event *","count":1}},"_error":{},"settings":{"input":"2022-09-20T00:37:11.134Z","input_format":"","input_tz":"Australia/Sydney","output_format":"YYYY-MM-DD HH:mm:ss","output_locale":"en_AU","output_tz":"Australia/Sydney"},"time":"2022-09-20 10:37:11","payload":{"message":"TypeError: Cannot read property 'colour' of undefined","source":{"id":"fed40e07.141c68","type":"function","name":"Ack event *","count":1}},"topic":"ERROR_REPORT/TelePi/Local Readings"}

```

Important part:

```auto
TypeError: Cannot read property 'colour' of undefined

```

So looking at the _sauce_ (sorry)

Function node with code:

```auto
// 2022 07 16 To fix undefined errors.
if (msg.payload.colour == undefined)
    msg.payload.colour = "red";

var x = msg.payload.colour;
var who = msg.payload.device;
var led_msg = msg.payload.led;
var event = msg.payload.event; // 2022 02 04 Added.
var more = flow.get("more_messages") || 0;
var msg2 = {};

// 2022 01 30 Still giving errors.
// 2022 02 04 Looking good.
var led = led_msg ? parseInt(led_msg.substring(4,5)) : 0

// See top of code
//// 2022 02 25 Fixing problem is msg.payload.colour is not set. (Probably at boot)
//if (x == undefined)
// x = "red";

node.warn("X " + x);
node.warn("Who " + who);
node.warn("led " + led_msg);

if (more > 0)
{
// x = "orange";
    //
    msg2.payload = {"background":"red","color":"black","label":"MORE"};
// msg2 = {"background":"red","color":"black","label":"MORE"};
}

if (more == 0)
{
    //
    node.warn("MORE = 0");
// msg2.payload = {"background":"darkgreen","color":"white","who":"ACK"};
    msg2.payload = {"background":"darkgreen","color":"white","label":"ACK"};
    led = context.get("old_led") || 0;
}

if (who == "All clear")
{
    //
    node.warn("ALL CLEAR");
    msg = {
        "payload": "rgb," + led + ",0,0,0", // Needed to handle varying led numbers
        "who":"All clear", // Depricated 2021 12 04
        "wipe":"CLEAR"
    };
    
    msg1 = {payload: '<font color = '+x+'><i class="fa fa-bullseye fa-2x"></i></font>',"who": "All Clr "}; // Should be `event`?
    //msg1 = {payload: '<font color = '+x+'><i class="fa fa-bullseye fa-2x"></i></font>',"who": event};
    //
}
else
{
    //
    msg.payload = led_msg;
    msg1 = {payload: '<font color = '+x+'><i class="fa fa-bullseye fa-2x"></i></font>',"who": who};
    //msg1 = {payload: '<font color = '+x+'><i class="fa fa-bullseye fa-2x"></i></font>',"who": event};

// node.warn("Colour " + x);
// node.warn("Who " + who);
// node.warn("Led " + led);
// node.warn("More " + more);

    context.set("old_led",led);

}

return [msg,msg1,msg2];

```

Forgive all the comments.

But looking at the top bit of it:

```auto
// 2022 07 16 To fix undefined errors.
if (msg.payload.colour == undefined)
    msg.payload.colour = "red";

var x = msg.payload.colour;

```

Unless `colour` is from somewhere else.

But those lines _should_ stop the problem for `x` getting `msg.payload.colour` if it not defined.

Thoughts?

---

<div class="post-metadata">

**Author:** ![Steve-Mcl](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/steve-mcl/32/4826_2.png) [@Steve-Mcl](https://discourse.nodered.org/u/Steve-Mcl)\
**Post date:** [20 September 2022 03:44 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/2 "2022-09-20T03:44:42Z")

</div>

> [@Trying\_to\_learn](#):
>
> Important part:
> 
> ```auto
> TypeError: Cannot read property 'colour' of undefined
> 
> ```

It is exactly as it says. Cannot read a property named colour from undefined. I.e. `msg.payload` is empty/null/undefined

Your test is inadequate.

> [@Trying\_to\_learn](#):
>
> ```auto
> if (msg.payload.colour == undefined)
> msg.payload.colour = "red";
> 
> ```

If `msg.payload` is undefined how can it check a sub property named colour? It can't.

  

You probably want something like this at the very top of the function...

```auto
if (msg.payload == null || typeof msg.payload !== "object") {
  node.error("payload must be an object", msg)
  return null
}

```

---

<div class="post-metadata">

**Author:** ![Trying\_to\_learn](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/trying_to_learn/32/28400_2.png) [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Post date:** [20 September 2022 04:49 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/3 "2022-09-20T04:49:22Z")

</div>

But the _idea_ is that the payloads **are** structured correctly.

But (from the machine's reboot) I see this:  
`{"_msgid":"772966b40bfa3282","_event":"node:eafdfa87.79d67"}`  
And that is way not what is supposed to coming in.

So the _sender_ is the `node` in the message?

But I will have to put something like what you showed me to catch any other messages sneaking through, into the node.

---

<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:** [20 September 2022 07:47 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/4 "2022-09-20T07:47:01Z")

</div>

Make sure you understand _why_ there is no payload, so you can fix that, or cope with it properly.

---

<div class="post-metadata">

**Author:** ![Trying\_to\_learn](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/trying_to_learn/32/28400_2.png) [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Post date:** [20 September 2022 07:48 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/5 "2022-09-20T07:48:14Z")

</div>

Yes, that is a good idea, but I don't think it is in my skill set.

Tracing the message, it only points to a `link out` node.

---

<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:** [20 September 2022 08:55 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/6 "2022-09-20T08:55:04Z")

</div>

Do you mean you have a message coming into a function node and you don't know where it is coming from? That is a disaster. How can you expect to have a stable system if you don't understand where messages are coming from?

Add a function node in the output of each node that feeds it (or feeds the link node) with a `warn() ` function if the payload is missing and you will identify it.

---

<div class="post-metadata">

**Author:** ![Trying\_to\_learn](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/trying_to_learn/32/28400_2.png) [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Post date:** [20 September 2022 08:58 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/7 "2022-09-20T08:58:33Z")

</div>

Well, when I looked at the message - as given to me by the system - and searched for the _originating_ node: all I was given was a `link out` node.

So that doesn't really help me, other than that part of the flow is sending it.

> [@Colin](#):
>
> How can you expect to have a stable system if you don't understand where messages are coming from?

I didn't make `node-red` so I can't answer the question as I see it.

![Screenshot from 2022-09-20 18-58-58](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/9/392fec4ddfc6ae5dee0bb5e985135e73add3b4b5.png)

 ![Screenshot from 2022-09-20 18-59-11](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/3/c/3c64360f65b697e57be35997816ad1af839f4a36.png)

---

<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:** [20 September 2022 10:58 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/8 "2022-09-20T10:58:31Z")

</div>

Is the link In node connected to the input of your failing function? If so then presumably it is coming from one of the link out nodes feeding that link in. So do what I suggested in my last post.

---

<div class="post-metadata">

**Author:** ![Trying\_to\_learn](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/trying_to_learn/32/28400_2.png) [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Post date:** [20 September 2022 11:14 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/9 "2022-09-20T11:14:01Z")

</div>

The message has a _this message is coming from node-id_.

You see I search for it and there is the `link in` and `link out` nodes.

**Obviously** it won't be the `link in` node, but saying it is form a `link out` node?

The _upstream_ nodes as shown.

---

<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:** [20 September 2022 20:05 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/10 "2022-09-20T20:05:22Z")

</div>

Is that node connected (via link in) to the function node?

---

<div class="post-metadata">

**Author:** ![Trying\_to\_learn](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/trying_to_learn/32/28400_2.png) [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Post date:** [20 September 2022 20:44 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/11 "2022-09-20T20:44:40Z")

</div>

_That_ and _the_.....

The `function` node that spits the error is connected via a `link out` and `link in` node and a subflow to another `function` node shown above called `Identifyh SOM/EOM EVENT`.

---

<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:** [20 September 2022 20:54 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/12 "2022-09-20T20:54:31Z")

</div>

I am talking about the inputs to the function node, it is there that the payload is missing

---

<div class="post-metadata">

**Author:** ![Trying\_to\_learn](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/trying_to_learn/32/28400_2.png) [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Post date:** [20 September 2022 21:00 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/13 "2022-09-20T21:00:33Z")

</div>

Yes, the node which reports/creates the error and part of who's code I posted at the start:

The input is from (via other `link` nodes) the node `identify SOM/EOM EVENT`

code:

```auto
if (msg.topic == "TIMESTAMP")
{
    return msg;
}
msg2 = {};

if (msg.type == "SOM")
{
    // SOM
    msg2.payload = 
    {
        "device":msg.payload,
        "what": "SOM message",
        "event": "SOM message",
        "led":"rgb,6,118,15,4",
        "colour":"orange"
    };
}
if (msg.type == "EOM")
{
    // EOM
    msg2.payload = 
    {
        "device":msg.payload,
        "what": "EOM message",
        "event": "EOM message",
        "led":"rgb,6,118,0,30",
        "colour":"orange"
    };
}

return msg2;

```

And now looking at that code:

```auto
if (msg.topic == "TIMESTAMP")
{
    return msg;
}

```

May be a problem.  
But in this (newer) specific case: `payload` would be set.  
But I guess I will need to address that problem also.

---

<div class="post-metadata">

**Author:** ![hotNipi](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/hotnipi/32/383_2.png) [@hotNipi](https://discourse.nodered.org/u/hotNipi)\
**Post date:** [21 September 2022 02:46 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/14 "2022-09-21T02:46:57Z")

</div>

```auto
if (msg.topic == "TIMESTAMP") {
    //correctly handled case where msg topic is TIMESTAMP, works as expected. 
    return msg;
}

// we are here because of "msg.topic" is not "TIMESTAMP"

// declared an empty object.
let msg2 = {};

// handling case where msg.type is string "SOM"
if (msg.type == "SOM") {
    // SOM

    // previously declared object "msg2" gets property "payload".
    msg2.payload =
    {
        "device": msg.payload,
        "what": "SOM message",
        "event": "SOM message",
        "led": "rgb,6,118,15,4",
        "colour": "orange"
    };
}

// if msg.type was something else or missing, the "msg2" is still an empty object

// handling case where msg.type is string "EOM"

if (msg.type == "EOM") {
    // EOM

    // previously declared object "msg2" gets property "payload".
    msg2.payload =
    {
        "device": msg.payload,
        "what": "EOM message",
        "event": "EOM message",
        "led": "rgb,6,118,0,30",
        "colour": "orange"
    };
}

// unhandled cases
// msg.type is missing ---> the "msg2" is an empty object
// msg.type is not "EOM" or "SOM" ---> the "msg2" is an empty object

// if empty object should not be passed downstream ... what can be done here?

return msg2;

```

---

<div class="post-metadata">

**Author:** ![Trying\_to\_learn](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/trying_to_learn/32/28400_2.png) [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Post date:** [21 September 2022 21:47 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/15 "2022-09-21T21:47:57Z")

</div>

Thanks for that.

What I wrote was an early attempt at that, but old _habits_ are seen with `var` rather than `let`.

(I'll now reply to all)

---

<div class="post-metadata">

**Author:** ![Trying\_to\_learn](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/trying_to_learn/32/28400_2.png) [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Post date:** [21 September 2022 22:00 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/16 "2022-09-21T22:00:55Z")

</div>

Ok, I am going to try and look at what is going on now while my hay fever is behaving.

The first bit that tests for `TIMESTAMP` is (probably) not the best but an _artifact_ of other nodes I wrote.

The _upstream_ node (Identify SOM/EOM EVENT) may be a duplicate node from part of the flow where it is logged.  
That part of the flow also gets _Timestamps_ (I press a button and it _time stamps_ (marks) the log with the time.)

This was problematic as when this node (or nodes similar) got the timestamp message, they would spit their dummy and error. So I put that part at the top to simply _pass on_ the message.

Things evolve and so that bit of code was propagated to others to avoid that problem.  
But! Looking at where THIS node is, the timestamp doesn't need to be passed on.  
So I guess I could simply `return` rather than `return msg`. But that is beside the point for the message I caught originally.

Some of this code is from when I was starting in NR and I hope I have grown since then. But (sorry) old things hang around and re-enforce the wrong habits when I am forced to look back and fix problems in the node/code.

I'll stop typing and action what I said above:  
I'll see if I can find what is causing the error.

Thanks to all.

---

<div class="post-metadata">

**Author:** ![Trying\_to\_learn](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/trying_to_learn/32/28400_2.png) [@Trying\_to\_learn](https://discourse.nodered.org/u/Trying_to_learn)\
**Post date:** [21 September 2022 23:06 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/17 "2022-09-21T23:06:16Z")

</div>

(I'm stuck)

Ok, things aren't quite as simple as I would like, but what else is new? ☹

So looking more at the node which is still getting the wrong kind of `msg`.

This is the start of the code:

```auto
if (msg.payload == null || typeof msg.payload !== "object")
{
    node.error("payload must be an object", msg);
    return null
}

```

Alas, the `node.error` is somewhat lost in the messages.  
(I've just realised I log the error messages)

But while I'm here.

Would this work:

```auto
if (msg.payload == null || typeof msg.payload !== "object")
{
    flow.set("ACK_ERROR",msg.payload);
    node.error("payload must be an object", msg);
    return null
}

```

So when that bit of code is run it sets the flow variable "ACK\_ERROR" to what the payload is?

Just wondering.

---

<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:** [20 November 2022 23:07 UTC](https://discourse.nodered.org/t/need-help-with-this-error/67953/18 "2022-11-20T23:07:00Z")

</div>

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