# Help for a loop functiopn

**URL:** <https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598>\
**Category:** General\
**Created:** [8 September 2020 14:54 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598 "2020-09-08T14:54:13Z")\
**Posts on this page:** 17\
**Page:** 1

<div class="post-metadata">

**Author:** ![stich86](https://avatars.discourse-cdn.com/v4/letter/s/b19c9b/32.png) [@stich86](https://discourse.nodered.org/u/stich86)\
**Post date:** [8 September 2020 14:54 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/1 "2020-09-08T14:54:14Z")

</div>

Hi guys,

i'm trying to create a flow that will output the sensors in alarm to Alexa before launch a script on Home-Assistant that will close all shutter and the arm the alarm.

Main problem is when i need to send the alert to Alexa (and don't execute the service call) or just execute service call where there is no alarm.

Here is the current flow:

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/d/d/ddffcdbd7e41d16ca85ea0f753171c601ed25342.png)

the function inside is this one:

```auto
var zone_status =[];
var zone_name = [];
var sensor_status = [];

// Infrarossi
zone_status[1] = msg.payload.zonesStatus.zone[2].status // Infrarosso Cameretta
zone_name[1] = "Infrarosso Cameretta"
zone_status[2] = msg.payload.zonesStatus.zone[3].status // Infrarosso Camera
zone_name[2] = "Infrarosso Camera"
zone_status[3] = msg.payload.zonesStatus.zone[5].status // Infrarosso Ingresso
zone_name[3] = "Infrarosso Ingresso"

// Tapparele
zone_status[4] = msg.payload.zonesStatus.zone[27].status // Tapparelle Camera
zone_name[4] = "Tapparelle Camera"
zone_status[5] = msg.payload.zonesStatus.zone[22].status // Tapparelle Salone
zone_name[5] = "Tapparelle Salone"
zone_status[6] = msg.payload.zonesStatus.zone[15].status // Tapparella Cameretta
zone_name[6] = "Tapparella Cameretta"
zone_status[7] = msg.payload.zonesStatus.zone[17].status // Tapparella Bagno
zone_name[7] = "Tapparella Bagno"
zone_status[8] = msg.payload.zonesStatus.zone[12].status // Tapparella Cucina
zone_name[8] = "Tapparella Cucina"

// Shock
zone_status[9] = msg.payload.zonesStatus.zone[10].status // Shock Cucina
zone_name[9] = "Shock Cucina"
zone_status[10] = msg.payload.zonesStatus.zone[13].status // Shock Cameretta
zone_name[10] = "Shock Cameretta"
zone_status[11] = msg.payload.zonesStatus.zone[16].status // Shock Bagno
zone_name[11] = "Shock Bagno"
zone_status[12] = msg.payload.zonesStatus.zone[18].status // Shock Salone Lunga
zone_name[12] = "Shock Salone Lunga"
zone_status[13] = msg.payload.zonesStatus.zone[20].status // Shock Salone Corta
zone_name[13] = "Shock Salone Corta"
zone_status[14] = msg.payload.zonesStatus.zone[23].status // Shock Camera Corta
zone_name[14] = "Shock Camera Corta"
zone_status[15] = msg.payload.zonesStatus.zone[25].status // Shock Camera Lunga
zone_name[15] = "Shock Camera Lunga"

// Magneti
zone_status[16] = msg.payload.zonesStatus.zone[4].status // Magnete Portone
zone_name[16] = "Magnete Portone"
zone_status[17] = msg.payload.zonesStatus.zone[11].status // Magnete Cucina
zone_name[17] = "Magnete Cucina"
zone_status[18] = msg.payload.zonesStatus.zone[14].status // Magnete Cameretta
zone_name[18] = "Magnete Cameretta"
zone_status[19] = msg.payload.zonesStatus.zone[19].status // Magnete Salone Lunga
zone_name[19] = "Magnete Salone Lunga"
zone_status[20] = msg.payload.zonesStatus.zone[21].status // Magnete Salone Corta
zone_name[20] = "Magnete Salone Corta"
zone_status[21] = msg.payload.zonesStatus.zone[24].status // Magnete Camera Corta
zone_name[21] = "Magnete Camera Corta"
zone_status[22] = msg.payload.zonesStatus.zone[26].status // Magnete Camera Lunga
zone_name[22] = "Magnete Camera Lunga"

// START FUNCTION
for (var i = 1; i < zone_status.length; i++) {
        if ((zone_status[i]) == "ALARM") {
                msg.payload = "Sensore" + (zone_name[i]) + " è in allarme,"
                node.send(msg)
            }
        else {
            msg.payload = "ok"
            node.send(msg)
        }
}

```

On the switch node i've put this configuration:

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/c/4/c409982b19397b03ad7d057964bd79015e65fb50.png)

but i looks like that also if the first check match, it hits also the "otherwise" when "stop at first match" is selected

Can you help me?

thanks!

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<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:** [8 September 2020 15:14 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/2 "2020-09-08T15:14:53Z")

</div>

What do you see in the debug node when you believe it is wrongly sending to the 'otherwise' output.

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<div class="post-metadata">

**Author:** ![stich86](https://avatars.discourse-cdn.com/v4/letter/s/b19c9b/32.png) [@stich86](https://discourse.nodered.org/u/stich86)\
**Post date:** [8 September 2020 15:16 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/3 "2020-09-08T15:16:47Z")

</div>

i see "ok", but the problem is that i shouldn't see anything if the first node (that check "allarme" word) should stop and avoid sending to the second output.

Is it right?

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<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:** [8 September 2020 15:20 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/4 "2020-09-08T15:20:21Z")

</div>

If you mean that the payload contains "ok" then it does not contain "allarme" so it _should_ be sent to output 2 (because the allarme test has failed).

**[Edit]** I wonder whether you meant to only send "ok" if none of the alarms is active. As you have it then you will get either an alarm message or an ok for every element of the array. If so then add a line before the loop  
`let ok = true`  
then in the else condition, instead of sending a message do  
`ok = false`  
the result will be that at the end of the loop the variable `ok` will tell you whether there were any alarms. Then you can add

```auto
if (ok ) {
  msg.payload = "ok"
  node.send(msg)
}

```

---

<div class="post-metadata">

**Author:** ![stich86](https://avatars.discourse-cdn.com/v4/letter/s/b19c9b/32.png) [@stich86](https://discourse.nodered.org/u/stich86)\
**Post date:** [8 September 2020 16:10 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/5 "2020-09-08T16:10:06Z")

</div>

> [@Colin](#):
>
> let ok = true

where i've to put the latest if?  
inside the else or outside the loop?

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<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:** [8 September 2020 16:13 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/6 "2020-09-08T16:13:07Z")

</div>

After the main loop, so it will run right through the array, sending alarm messages if necessary, then after that is finished it will send ok if it did not find any alarms.

---

<div class="post-metadata">

**Author:** ![stich86](https://avatars.discourse-cdn.com/v4/letter/s/b19c9b/32.png) [@stich86](https://discourse.nodered.org/u/stich86)\
**Post date:** [8 September 2020 16:32 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/7 "2020-09-08T16:32:33Z")

</div>

in that way?

```auto
// START FUNCTION
let ok = true
for (var i = 1; i < zone_status.length; i++) {
        if ((zone_status[i]) == "AALARM") {
                msg.payload = "Sensore" + (zone_name[i]) + " è in allarme,"
                node.send(msg)
            }
        else {
            ok = false
        }
}

if (ok) {
    node.send(msg)
}

```

---

<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:** [8 September 2020 17:07 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/8 "2020-09-08T17:07:52Z")

</div>

What do you think yourself looking at the code and working out what it does?

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<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:** [8 September 2020 17:09 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/9 "2020-09-08T17:09:41Z")

</div>

You have lost the `msg.payload = "ok"`

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<div class="post-metadata">

**Author:** ![stich86](https://avatars.discourse-cdn.com/v4/letter/s/b19c9b/32.png) [@stich86](https://discourse.nodered.org/u/stich86)\
**Post date:** [9 September 2020 07:07 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/10 "2020-09-09T07:07:15Z")

</div>

> [@Colin](#):
>
> `msg.payload = "ok"`

```auto
// START FUNCTION
let ok = true
for (var i = 1; i < zone_status.length; i++) {
        if ((zone_status[i]) == "ALARM") {
                msg.payload = "Sensore" + (zone_name[i]) + " è in allarme,"
                node.send(msg)
            }
        else {
            ok = false
        }
}

if (ok) {
    msg.payload = "ok"
    node.send(msg)
}

```

ok, i've fixed the code, but when no "alert", the second output of the switch is not triggered

---

<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:** [9 September 2020 08:34 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/11 "2020-09-09T08:34:07Z")

</div>

Sorry, the changes I suggested are all wrong. So wrong that I am surprised you did not see it when working out what it does :). You don't need the else at all, it should set ok to false whenever it sends a alarm message, so that it won't send ok if it sends any alarms.

```auto
let ok = true
for (var i = 1; i < zone_status.length; i++) {
        if ((zone_status[i]) == "ALARM") {
                msg.payload = "Sensore" + (zone_name[i]) + " è in allarme,"
                node.send(msg)
                ok = false
            }
}

if (ok) {
    msg.payload = "ok"
    node.send(msg)
}

```

---

<div class="post-metadata">

**Author:** ![stich86](https://avatars.discourse-cdn.com/v4/letter/s/b19c9b/32.png) [@stich86](https://discourse.nodered.org/u/stich86)\
**Post date:** [9 September 2020 09:35 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/12 "2020-09-09T09:35:33Z")

</div>

yes sorry but i'm not so expert ^\_^"  
removing else and put the check out of the loop gives me the expected result!

thank you so much 🙂

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<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:** [9 September 2020 09:38 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/13 "2020-09-09T09:38:37Z")

</div>

> [@stich86](#):
>
> yes sorry but i'm not so expert ^\_^"

Neither am I it seems, or I would not have posted rubbish in the first place.

---

<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:** [9 September 2020 10:26 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/14 "2020-09-09T10:26:29Z")

</div>

@stich86

@Colin latest posted code will work fine but you might his a subtle bug due to `msg` being an object so settings `msg.payload` for each alarm actually changes the value of `.payload` for already sent messages & _could_ impact your flows in odd ways.

To avoid this possible anomaly, you might want to consider sending new messages...

```auto
let ok = true;
for (let i = 1; i < zone_status.length; i++) {
  if ((zone_status[i]) == "ALARM") {
    //alarm found - create and send a new message object...
    let m = { payload: "Sensore" + (zone_name[i]) + " è in allarme," }
    node.send(m);
    ok = false;
  }
}

if (ok) {
  msg.payload = "ok"
  node.send(msg)
}

```

---

<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:** [9 September 2020 11:30 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/15 "2020-09-09T11:30:24Z")

</div>

I think this is not an issue as `node.send()` always clones the message before sending it.

---

<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:** [9 September 2020 12:08 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/16 "2020-09-09T12:08:56Z")

</div>

DOH - I keep forgetting that...

> [@tada Node-RED 1.0.0-beta.4 released](https://discourse.nodered.org/t/node-red-1-0-0-beta-4-released/15577/1):
>
> This release, as I described on the [blog last week](https://nodered.org/blog/2019/09/13/cloning-messages), changes the default behaviour of the Function node to always clone messages passed to `node.send()` .

... I suppose its because in custom node development, the opposite is true 🤷‍♂️

@stich86 ignore my previous post 😃

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<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:** [8 November 2020 12:09 UTC](https://discourse.nodered.org/t/help-for-a-loop-functiopn/32598/17 "2020-11-08T12:09:01Z")

</div>

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