# Can someone look at this - is there a problem with the \`moment\` node?

**URL:** <https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521>\
**Category:** General\
**Created:** [25 September 2021 21:25 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521 "2021-09-25T21:25:24Z")\
**Posts on this page:** 20\
**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:** [25 September 2021 21:25 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/1 "2021-09-25T21:25:24Z")

</div>

I was about to help someone and while writing a flow and using the `moment` node I noticed some weird happenings.

Here is a _working_ version:

```auto
[{"id":"b036bcbd7e968d27","type":"function","z":"65c9b63cb09879a0","name":"","func":"msg1 = {};\nvar last = context.get(\"last\") || 0;\n//node.warn(\"Last \" + last);\n\nvar now = msg.payload;\n//node.warn(\"Now \" + now);\n\nvar diff = now - last;\n//node.warn(\"Diff \" + diff);\n\ncontext.set(\"last\",now);\nmsg.payload = diff;\nmsg1.payload = last;\nreturn [msg,msg1];","outputs":2,"noerr":0,"initialize":"","finalize":"","libs":[],"x":1690,"y":440,"wires":[["854e8054259d8865"],["29f6c4455848f54b"]]},{"id":"5b1517de26decbd9","type":"inject","z":"65c9b63cb09879a0","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":1530,"y":440,"wires":[["b036bcbd7e968d27","2a950ded67900e92"]]},{"id":"854e8054259d8865","type":"moment","z":"65c9b63cb09879a0","name":"","topic":"","input":"payload","inputType":"msg","inTz":"Australia/Sydney","adjAmount":0,"adjType":"days","adjDir":"add","format":"mm:ss","locale":"en-AU","output":"payload","outputType":"msg","outTz":"Australia/Sydney","x":1870,"y":440,"wires":[["b20ec09a7b4ecb1e"]]},{"id":"29f6c4455848f54b","type":"moment","z":"65c9b63cb09879a0","name":"","topic":"","input":"","inputType":"msg","inTz":"Australia/Sydney","adjAmount":0,"adjType":"days","adjDir":"add","format":"HH:mm:ss","locale":"en-AU","output":"","outputType":"msg","outTz":"Australia/Sydney","x":1870,"y":530,"wires":[["b50cd4588cac6937"]]},{"id":"2a950ded67900e92","type":"moment","z":"65c9b63cb09879a0","name":"","topic":"","input":"","inputType":"msg","inTz":"Australia/Sydney","adjAmount":0,"adjType":"days","adjDir":"add","format":"HH:mm:ss","locale":"en-AU","output":"","outputType":"msg","outTz":"Australia/Sydney","x":1730,"y":350,"wires":[["56370474810d5420"]]},{"id":"b20ec09a7b4ecb1e","type":"debug","z":"65c9b63cb09879a0","name":"diff","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":1890,"y":390,"wires":[]},{"id":"b50cd4588cac6937","type":"debug","z":"65c9b63cb09879a0","name":"last","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":1890,"y":480,"wires":[]},{"id":"56370474810d5420","type":"debug","z":"65c9b63cb09879a0","name":"Time","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":1900,"y":350,"wires":[]}]

```

I have extra things shown (_available_) to help me check it is/was working.

Within a second things seem to add up - but for the first time.

So, where's the problem?

The `moment` node going to the `diff` debug node.

It is set to show `mm:ss` Minutes and Seconds.

But!

If I make it `HH:mm:ss` it ALWAYS shows `10` hours!

Is that a bug?

---

<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:** [25 September 2021 21:39 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/2 "2021-09-25T21:39:02Z")

</div>

When I add the HH I get the hours minutes and seconds.

What version of NR and what version of the moment node are you using (check it in the palette manager)

---

<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:** [25 September 2021 21:44 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/3 "2021-09-25T21:44:32Z")

</div>

NR 2.0.1  
Moment 4.0.0

So `HH` alone gives you hours, minutes and seconds?

I don't. All I get is the Hours...

 ![Screenshot from 2021-09-26 07-48-27](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/8/6/869606e29714815655fe5b37a1621926a3fe97fa.png)

---

<div class="post-metadata">

**Author:** ![jbudd](https://avatars.discourse-cdn.com/v4/letter/j/5f8ce5/32.png) [@jbudd](https://discourse.nodered.org/u/jbudd)\
**Post date:** [25 September 2021 21:51 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/4 "2021-09-25T21:51:31Z")

</div>

Where are you?

I see the various timezones are set to Australia/Sydney, which is currently 10 hours ahead of UTC.

If I change them all to my timezone Europe/London, instead of 10 hours I get 1 hour. Clock time here is currently 1 hour ahead of UTC.

People keep reassuring me that "you dont have to worry about timezones, it just works" but my experience is it just doesn't.

---

<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:** [25 September 2021 21:55 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/5 "2021-09-25T21:55:06Z")

</div>

Yes, I am in Sydney.

Yikes! That is a _problem_.  
Though I know _GMT_ (Or _ZULU_) time is a standard.

But I am ... kind of lazy. I don't use it enough to look at that.  
('T would be nice if the time zone was a _drop down pick_ option)  
What do I enter to make it ZULU?

---

<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:** [25 September 2021 22:02 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/6 "2021-09-25T22:02:21Z")

</div>

No not alone but if I put just HH in, right now I get 08 (I’m on the east coast of the US)

---

<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:** [25 September 2021 22:02 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/7 "2021-09-25T22:02:26Z")

</div>

I'm not exactly sold on that though.

This is the maths which determines the difference:

```auto
msg1 = {};
var last = context.get("last") || 0;
//node.warn("Last " + last);

var now = msg.payload;
//node.warn("Now " + now);

var diff = now - last;
//node.warn("Diff " + diff);

context.set("last",now);
msg.payload = diff;
msg1.payload = last;
return [msg,msg1];

```

(Yeah, with a bit of debugging output)

It is spitting out the correct value.

Ok, so the `moment` node gets that value (say only seconds passed)

It shouldn't (by my thinking) be adding 10 hours.

If that is true (correct) it makes living in any other time zone painful if doing time calculations.

So to clarify:  
`timestamp` is ALWAYS ZULU time?  
Which I can kind of understand.

But allowing time zones to _tweak_ the value is confusing and can catch better people than I out, I am sure.

---

<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:** [25 September 2021 22:03 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/8 "2021-09-25T22:03:57Z")

</div>

Sorry. I was not sure what you meant by you saying:

> [@zenofmud](#):
>
> When I add the HH I get the hours minutes and seconds.

In retrospect - now - if I make it HH:mm:ss and take away 10 hours I get the right answer.

But to me that is confusing the situation.

---

<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:** [25 September 2021 22:06 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/10 "2021-09-25T22:06:21Z")

</div>

Agreed.  
I just posted if I subtract 10 hours in the `moment` node I get the right answer.

But I am thrown because _it_ is including the timezone in something which is nothing to do with time zones.

It is "how long between these two time stamps".

---

<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:** [25 September 2021 22:06 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/11 "2021-09-25T22:06:29Z")

</div>

If you look at the ` Help` for the ` inject` node it says

> The default payload is a timestamp of the current time in millisecs since January 1st, 1970.

I don’t know if you know this, but if you click on the timestamp in the debug sidebar, it will rotate thre different formats of the timestamp

---

<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:** [25 September 2021 22:08 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/12 "2021-09-25T22:08:04Z")

</div>

And again: I agree.

But that the `moment` node _includes_ the time zone when the timezone isn't part of the equation is annoying.

I shall really have to write myself a big note about this if/when doing time calculations in the future that I need to `-10 hours` in the 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:** [25 September 2021 22:12 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/13 "2021-09-25T22:12:01Z")

</div>

(I am also confused: to whom do I give credit for _solving_ this problem?)  
I _goofed_ by forgetting to include the TIMEZONE offset and subtract it.

# Note to anyone reading this who has a similar problem:

If you are wanting **TIME BETWEEN** values, you **MUST** adjust the output by adding/subtracting the timezone value in the `moment` node, or you will be getting _weird_ hour values returning.

---

<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:** [25 September 2021 22:15 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/15 "2021-09-25T22:15:44Z")

</div>

I am _lucky_ in that all my stuff is local and I am not exposing it to external places.

That scenario is (still) beyond my understanding of how to handle it.  
And probably will be forever in a day.

To me that is/should be handled at a higher level.

---

<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:** [25 September 2021 22:19 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/17 "2021-09-25T22:19:51Z")

</div>

> [@jbudd](#):
>
> It would all be much simpler if the earth was a bit flatter.

But that would make it easier to fall off!!!

---

<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:** [25 September 2021 22:21 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/19 "2021-09-25T22:21:06Z")

</div>

Sorry, that isn't helping.

I am guessing it is ironic (or sarcastic?).

I am wanting to get the **difference** between two time stamps sent into the function node - which it does quite happily.

It then displays the difference formatted as HH:mm:ss.  
The fact I have to `-10` hours to allow for my offset is confusing.

It caught me out. And probably not the first time. I'll admit that.  
But I am (I really hope) that it won't catch me again.

---

<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:** [25 September 2021 22:27 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/20 "2021-09-25T22:27:16Z")

</div>

Hang on.....

I'm now even more confused.

`inject` node....----\> `moment` node.....---\>`debug` node.

Nothing added.

Press the `inject` and I get/see the time.. ZULU TIME.  
The input and OUTPUT timezones are set to Sydney.

So, if the TIMEZONE is set to SYDNEY: why am I getting ZULU time?  
(Moving on)

If I change the output FORMAT to HH:mm:ss why does it suddenly change it to LOCAL TIME?

To me that is a big problem.  
Could someone help me get my head around that?

FORMAT (to me) is **nothing to do with** time zone.

---

<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:** [26 September 2021 09:43 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/21 "2021-09-26T09:43:12Z")

</div>

> [@Trying\_to\_learn](#):
>
> The input and OUTPUT timezones are set to Sydney.  
> So, if the TIMEZONE is set to SYDNEY: why am I getting ZULU time?

1. If the input value is a timestamp then the node ignores the Input Timezone, since a timestamp is by definition UTC.
2. If you don't specify a format then note that the format field shows the default which is 'ISO8601 (UTC)'. So you have specified there that you want the output in UTC, which implies that the Output Timezone is again ignored.

> [@Trying\_to\_learn](#):
>
> If I change the output FORMAT to HH:mm:ss why does it suddenly change it to LOCAL TIME?

Because with that output format it is possible for it to apply the output timezone.

---

<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:** [26 September 2021 09:50 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/22 "2021-09-26T09:50:16Z")

</div>

> [@Trying\_to\_learn](#):
>
> If you are wanting **TIME BETWEEN** values, you **MUST** adjust the output by adding/subtracting the timezone value in the `moment` node, or you will be getting _weird_ hour values returning.

Much better is to _always_ work internally in UTC, only converting to local time for display and user input. Then you don't need to make any adjustments when calculating time between.

---

<div class="post-metadata">

**Author:** ![TotallyInformation](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/totallyinformation/32/31_2.png) [@TotallyInformation](https://discourse.nodered.org/u/TotallyInformation)\
**Post date:** [26 September 2021 13:15 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/23 "2021-09-26T13:15:35Z")

</div>

> [@Trying\_to\_learn](#):
>
> But that the `moment` node _includes_ the time zone when the timezone isn't part of the equation is annoying.

You could always raise an issue with the author 😉

Honestly, the moment node hasn't had much love recently as I'm focused on uibuilder and it needs rewriting anyway since momentjs is a dead project.

> [@Trying\_to\_learn](#):
>
> If you are wanting **TIME BETWEEN** values, you **MUST** adjust the output by adding/subtracting the timezone value in the `moment` node, or you will be getting _weird_ hour values returning.

The moment node was designed to handle date/time formatting and timezone inputs/outputs. Anything else is icing on the cake. So yes, you should be paying attention to timezones.

And yes, if you don't live in Greenwich, London, you have a time problem 🤣

Rule number 1 for computing and date/time computations is to keep all data in UTC and only use local time for user inputs and outputs. Any other approach WILL eventually bite you somewhere you don't want to be bitten. Date/Time calculations are hellishly complex and have dozens of edge-cases that few people know about. One of the things that I learned early on in my IT career (40+ years ago now!).

---

<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:** [26 September 2021 21:12 UTC](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521/24 "2021-09-26T21:12:48Z")

</div>

> [@Colin](#):
>
> Much better is to _always_ work internally in UTC, only converting to local time for display and user input. Then you don't need to make any adjustments when calculating time between.

I've still got to read Paul's reply.

AFAIK, that is exactly what I am/was doing.

Input a `timestamp`.  
That goes into a `function` node that stores it. (First time)  
Next time (or when a previous value is stored: Subtracts the two and gives the _time between_ the messages.  
That is then sent to the `moment` node to convert it to _user friendly_ format.

But there is confusion that I have to `-10 hours` to offset the timezone.

If the code is ONLY on this machine: anyone from anywhere can read it and get the right answer (given I `-10 hours`).

But it makes the code not universal because if I give it to anyone in another timezone, they have to edit the value.

[Next page](https://discourse.nodered.org/t/can-someone-look-at-this-is-there-a-problem-with-the-moment-node/51521.md?page=2)