# Interpretation of a QR Code

**URL:** <https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827>\
**Category:** Industrial\
**Tags:** function-node\
**Created:** [20 June 2024 20:24 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827 "2024-06-20T20:24:27Z")\
**Posts on this page:** 10\
**Page:** 1

<div class="post-metadata">

**Author:** ![pgenoud](https://avatars.discourse-cdn.com/v4/letter/p/a587f6/32.png) [@pgenoud](https://discourse.nodered.org/u/pgenoud)\
**Post date:** [20 June 2024 20:24 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827/1 "2024-06-20T20:24:27Z")

</div>

Hi all !

I'm starting with Node RED and discovering this amazing world !  
I work in the industry and will use node red for data acquisition in a product tracability subject.

My subject today is the following :

I will install a camera made to scan QR Codes. This camera is connected to a device running Node RED.  
I need some help to create the flow to interpret the message that will be send by the camera.

Here is the structure of the message in my QR Code :  
ProductName\_ProductFormat\_ProductDimension\_Component\_BatchNumber\_SubBatchNumber-ProductNumber1\_ProductNumber2\_...\_ProductNumberN

Example :  
HARDCOVER\_LANDSCAPE\_H21\_INNER\_074\_241UCNE9- A0000012492554\_A0000012492555\_...\_A0000012492565

Another one :  
SOFTCOVER\_PORTRAIT\_H28\_COVER\_085\_852NNE5-A0000013492896\_A0000013492875\_...

The number of products is not fixed (that's why I putted N products).

What I would like to get in output is :  
First message :  
ProductName = HARDCOVER  
ProductFormat = LANDSCAPE  
ProductDimension = H21  
Component = INNER  
BatchNumber = 074  
SubBatchNumber = 241UCNE9  
ProductNumber = A0000012492554

N message :  
ProductName = HARDCOVER  
ProductFormat = LANDSCAPE  
ProductDimension = H21  
Component = INNER  
BatchNumber = 074  
SubBatchNumber = 241UCNE9  
ProductNumber = A0000012492565

I would like to get a message every 0.5 secondes.

My final goal is to transfer these messages via the API of my software and store the datas in a Table :

| ProductName | ProductFormat | ProductDimension | Component | BatchNumber | SubBatchNumber | ProductNumber |
| --- | --- | --- | --- | --- | --- | --- |
| HARDCOVER | LANDSCAPE | H21 | INNER | 74 | 241UCNE9 | A0000012492554 |
| HARDCOVER | LANDSCAPE | H21 | INNER | 74 | 241UCNE9 | A0000012492555 |
| … | … | … | … | … | … | … |
| HARDCOVER | LANDSCAPE | H21 | INNER | 74 | 241UCNE9 | A0000012492565 |

My goal is to use as less code as possible and to try to use the Low Code force of Node RED.

I hope everything I said is clear...  
Thanks a lot for your tips !

---

<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:** [21 June 2024 06:14 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827/3 "2024-06-21T06:14:40Z")

</div>

Apologies, I did not notice you said a QR code may have more than one ProductNumber

---

<div class="post-metadata">

**Author:** ![edje11](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/edje11/32/572_2.png) [@edje11](https://discourse.nodered.org/u/edje11)\
**Post date:** [21 June 2024 06:37 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827/4 "2024-06-21T06:37:46Z")

</div>

The split command in a function node should do the job

```auto
let qrtext = "HARDCOVER_LANDSCAPE_H21_INNER_074_241UCNE9- A0000012492554_A0000012492555_..._A0000012492565";
msg.payload = qrtext.split("_");

```

---

<div class="post-metadata">

**Author:** ![bakman2](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/bakman2/32/6207_2.png) [@bakman2](https://discourse.nodered.org/u/bakman2)\
**Post date:** [21 June 2024 06:57 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827/5 "2024-06-21T06:57:45Z")

</div>

assuming msg.payload to be something like  
`HARDCOVER_LANDSCAPE_H21_INNER_074_241UCNE9A0000012492554_A0000012492555_..._A0000012492565`

You could use a csv node, set the separator to other: \_

Specify the column names; `ProductName,ProductFormat,ProductDimension,Component,BatchNumber,SubBatchNumber,ProductNumber`

and you get an object that you can sent to an api (depending on what it is expecting ofcourse).

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/f/c/fc4cae69a3dc9d5fbb60b46d01f3703a3790b63b.png)

---

<div class="post-metadata">

**Author:** ![E1cid](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/e1cid/32/77971_2.png) [@E1cid](https://discourse.nodered.org/u/E1cid)\
**Post date:** [21 June 2024 07:18 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827/6 "2024-06-21T07:18:06Z")

</div>

Passing the string through a change node with the JSONata expression

```auto
(
    $parts := $split($$.payload, "-");
    $temp := $split($parts[0], "_");
    $split($parts[1], "_").{
        "ProductName": $temp[0],
        "ProductFormat": $temp[1],
        "ProductDimension": $temp[2],
        "Component": $temp[3],
        "_BatchNumber": $temp[4],
        "SubBatchNumber": $temp[5],
        "ProductNumber": $
    }
)

```

will produce an array of objects  
e.g.

```auto
[
    {
        "ProductName": "HARDCOVER",
        "ProductFormat": "LANDSCAPE",
        "ProductDimension": "H21",
        "Component": "INNER",
        "BatchNumber": "074",
        "SubBatchNumber": "241UCNE9",
        "ProductNumber": " A0000012492554"
    },
    {
        "ProductName": "HARDCOVER",
        "ProductFormat": "LANDSCAPE",
        "ProductDimension": "H21",
        "Component": "INNER",
        "BatchNumber": "074",
        "SubBatchNumber": "241UCNE9",
        "ProductNumber": "A0000012492555"
    },
    {
        "ProductName": "HARDCOVER",
        "ProductFormat": "LANDSCAPE",
        "ProductDimension": "H21",
        "Component": "INNER",
        "BatchNumber": "074",
        "SubBatchNumber": "241UCNE9",
        "ProductNumber": "A0000012492565"
    }
]

```

which you can the split and rate limit.

example flow

```auto
[{"id":"19ead9e2436a8834","type":"inject","z":"d1395164b4eec73e","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"HARDCOVER_LANDSCAPE_H21_INNER_074_241UCNE9- A0000012492554_A0000012492555_A0000012492565","payloadType":"str","x":130,"y":4780,"wires":[["989b3b0e0caa2c69"]]},{"id":"0875332341da5d2b","type":"debug","z":"d1395164b4eec73e","name":"debug 2557","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":510,"y":4720,"wires":[]},{"id":"989b3b0e0caa2c69","type":"change","z":"d1395164b4eec73e","name":"","rules":[{"t":"set","p":"payload","pt":"msg","to":"(\t $parts := $split($$.payload, \"-\");\t $temp := $split($parts[0], \"_\");\t $split($parts[1], \"_\").{\t \"ProductName\": $temp[0],\t \"ProductFormat\": $temp[1],\t \"ProductDimension\": $temp[2],\t \"Component\": $temp[3],\t \"_BatchNumber\": $temp[4],\t \"SubBatchNumber\": $temp[5],\t \"ProductNumber\": $\t }\t)","tot":"jsonata"}],"action":"","property":"","from":"","to":"","reg":false,"x":280,"y":4780,"wires":[["0875332341da5d2b","217d3c59d0dc6922"]]},{"id":"217d3c59d0dc6922","type":"split","z":"d1395164b4eec73e","name":"","splt":"\\n","spltType":"str","arraySplt":1,"arraySpltType":"len","stream":false,"addname":"","x":490,"y":4780,"wires":[["474273521cec5219"]]},{"id":"ac0de4b31034ea31","type":"debug","z":"d1395164b4eec73e","name":"debug 2558","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","statusVal":"","statusType":"auto","x":530,"y":4840,"wires":[]},{"id":"474273521cec5219","type":"delay","z":"d1395164b4eec73e","name":"","pauseType":"rate","timeout":"5","timeoutUnits":"seconds","rate":"2","nbRateUnits":"1","rateUnits":"second","randomFirst":"1","randomLast":"5","randomUnits":"seconds","drop":false,"allowrate":false,"outputs":1,"x":630,"y":4780,"wires":[["ac0de4b31034ea31"]]}]

```

---

<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:** [21 June 2024 07:28 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827/7 "2024-06-21T07:28:06Z")

</div>

> [@pgenoud](#):
>
> My goal is to use as less code as possible and to try to use the Low Code force of Node RED

Sometimes, a function with code is the right answer. In this case, you have a highly proprietary format of data that you need to reuse portion of to generate table rows.

Had this data been stored in an easily parse-able format (like JSON or XML) then it might have been different.

Dont get me wrong, it _IS_ possible in low code but it will not be pretty nor super readable.

### Look maa, no-code, no JS, no JSONata

 ![image](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/3X/5/a/5afe8e643e726b79601326a7a50ee7d0f9b3f380.png)

```auto
[{"id":"5aa40c0210472df1","type":"template","z":"c37c71daed7c269d","name":"data","field":"payload","fieldType":"msg","format":"text","syntax":"plain","template":"HARDCOVER_LANDSCAPE_H21_INNER_074_241UCNE9-A0000012492554_A0000012492555_A0000012492565","output":"str","x":510,"y":1900,"wires":[["c38e9e43b6852505"]]},{"id":"240693f2c4adc3f0","type":"inject","z":"c37c71daed7c269d","name":"","repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"","payloadType":"date","x":360,"y":1900,"wires":[["5aa40c0210472df1"]]},{"id":"c38e9e43b6852505","type":"split","z":"c37c71daed7c269d","name":"split fixed data / part nos","splt":"-","spltType":"str","arraySplt":1,"arraySpltType":"len","stream":false,"addname":"","x":710,"y":1900,"wires":[["8eafcd416ea7e4bb"]]},{"id":"8eafcd416ea7e4bb","type":"join","z":"c37c71daed7c269d","name":"","mode":"custom","build":"array","property":"payload","propertyType":"msg","key":"topic","joiner":",","joinerType":"str","accumulate":false,"timeout":"","count":"2","reduceRight":false,"reduceExp":"$append($A,[{\t \"name\": payload,\t \"index\": $I\t}])","reduceInit":"[]","reduceInitType":"json","reduceFixup":"","x":910,"y":1900,"wires":[["aee5de86886bd5d6","e1e6b10dbdd03484"]]},{"id":"aee5de86886bd5d6","type":"debug","z":"c37c71daed7c269d","name":"","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","x":1090,"y":1900,"wires":[]},{"id":"e1e6b10dbdd03484","type":"change","z":"c37c71daed7c269d","name":"","rules":[{"t":"set","p":"fixed","pt":"msg","to":"payload[0]","tot":"msg"},{"t":"set","p":"partNos","pt":"msg","to":"payload[1]","tot":"msg"},{"t":"set","p":"payload","pt":"msg","to":"fixed","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":400,"y":1980,"wires":[["31e92a43546e5ff1"]]},{"id":"31e92a43546e5ff1","type":"csv","z":"c37c71daed7c269d","name":"parse fixed part","sep":"_","hdrin":"","hdrout":"none","multi":"one","ret":"\\n","temp":"ProductName,ProductFormat,ProductDimension,Component,BatchNumber,SubBatchNumber,ProductNumber","skip":"0","strings":true,"include_empty_strings":"","include_null_values":"","x":590,"y":1980,"wires":[["0daee601b38ce9aa"]]},{"id":"0daee601b38ce9aa","type":"change","z":"c37c71daed7c269d","name":"move fixed part to fixedValues","rules":[{"t":"set","p":"fixedValues","pt":"msg","to":"payload","tot":"msg"},{"t":"set","p":"payload","pt":"msg","to":"partNos","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":830,"y":1980,"wires":[["4df33c1bf7d858f2","59e18245f3a6b23a"]]},{"id":"4df33c1bf7d858f2","type":"debug","z":"c37c71daed7c269d","name":"debug 7","active":false,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":1080,"y":1980,"wires":[]},{"id":"59e18245f3a6b23a","type":"split","z":"c37c71daed7c269d","name":"split fixed data / part nos","splt":"_","spltType":"str","arraySplt":1,"arraySpltType":"len","stream":false,"addname":"","x":430,"y":2060,"wires":[["6adb6e4ad2cd9846"]]},{"id":"e4599ef1c3157c4f","type":"debug","z":"c37c71daed7c269d","name":"debug 8","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"payload","targetType":"msg","statusVal":"","statusType":"auto","x":1080,"y":2060,"wires":[]},{"id":"6adb6e4ad2cd9846","type":"change","z":"c37c71daed7c269d","name":"make final object","rules":[{"t":"set","p":"thisRow","pt":"msg","to":"fixedValues","tot":"msg","dc":true},{"t":"set","p":"thisRow.ProductNumber","pt":"msg","to":"payload","tot":"msg"},{"t":"move","p":"thisRow","pt":"msg","to":"payload","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":690,"y":2060,"wires":[["e4599ef1c3157c4f"]]}]

```

---

<div class="post-metadata">

**Author:** ![pgenoud](https://avatars.discourse-cdn.com/v4/letter/p/a587f6/32.png) [@pgenoud](https://discourse.nodered.org/u/pgenoud)\
**Post date:** [21 June 2024 08:22 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827/8 "2024-06-21T08:22:42Z")

</div>

Hi everyone !

Thanks a lot for all your help ! I managed to do what I wanted.

I know that coding is sometime the right answer but Low Code is easier to understand when you don't know (yet) JavaScript.

---

<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:** [21 June 2024 09:20 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827/9 "2024-06-21T09:20:28Z")

</div>

Would you care to share your solution?

---

<div class="post-metadata">

**Author:** ![pgenoud](https://avatars.discourse-cdn.com/v4/letter/p/a587f6/32.png) [@pgenoud](https://discourse.nodered.org/u/pgenoud)\
**Post date:** [21 June 2024 11:46 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827/10 "2024-06-21T11:46:44Z")

</div>

I used the solution given by @Steve-Mcl and it works perfectly !

---

<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:** [5 July 2024 11:47 UTC](https://discourse.nodered.org/t/interpretation-of-a-qr-code/88827/11 "2024-07-05T11:47:13Z")

</div>

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