While Loop in Node Red - arrays

Question

I have one system that is connected to some sensors. The main job is to send error numbers when one or more of the sensors are on.
In order to print the error description I have one csv-File with two columns, the first one with the numbers and the second one with the description.
In order to make this task I have created one flow in Node-Red:
In one line I save the array with the error numbers coming from the system in one flow variable (RandomNum).
In another line I read the csv-file with the error description, I transform it in an array of objects and then in fuction node I make a search in order to find the error number and the description.
The search function has as entance the array of objects. I save the flow variable (RandomNum) in an array (ranNum) and I define a new array (newMsg) where I save the description of the errors.
Then I use a while-loop in order to go through the array of objects and compare the value of the first column of this array with the number in ranNum. Then I save the description of the error in the array newMsg and I do this while-loop for each value of the ranNum array.
And here is my problem. When I execute the flow, it works correctly for the first value of the array ranNum but only for this. I get only the description of the first number in the ranNum array as payload, it looks like as the while-loop is used only once, and then it breaks and gives me the array newMsg.
When I check in the Conetxt, RandomNum is one array,
An when I ask to get the array ranNum, it's also an array,
I have check the while-loop at least 20-times, and I have did not found why it does not work.
Can anyone help me with this topic? Is there a problem with the flow variable or there is big difference between JavaScript and NodeJS that I did not found?
Here is the flow I have created:
[
{
"id": "b1d8b61d0ed5a5da",
"type": "tab",
"label": "Flow Test",
"disabled": false,
"info": ""
},
{
"id": "d677b342ccc51f1b",
"type": "inject",
"z": "b1d8b61d0ed5a5da",
"name": "",
"props": [
{
"p": "payload"
},
{
"p": "topic",
"vt": "str"
}
],
"repeat": "",
"crontab": "",
"once": false,
"onceDelay": 0.1,
"topic": "",
"payload": "",
"payloadType": "date",
"x": 140,
"y": 280,
"wires": [
[
"e2d5187d2e705892",
"a167b5a81e0b36ba"
]
]
},
{
"id": "7aa6e0bcbdf67c1c",
"type": "file in",
"z": "b1d8b61d0ed5a5da",
"name": "ReadAlarms",
"filename": "/home/DMT/Dokumente/DB_Test/alarms.csv",
"format": "utf8",
"chunk": false,
"sendError": false,
"encoding": "none",
"allProps": false,
"x": 530,
"y": 280,
"wires": [
[
"f2ab599d26fd7ca5",
"94ae4b1ea29d9fe2"
]
]
},
{
"id": "f2ab599d26fd7ca5",
"type": "debug",
"z": "b1d8b61d0ed5a5da",
"name": "",
"active": false,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "false",
"statusVal": "",
"statusType": "auto",
"x": 750,
"y": 220,
"wires": []
},
{
"id": "94ae4b1ea29d9fe2",
"type": "csv",
"z": "b1d8b61d0ed5a5da",
"name": "ConvertAlarms",
"sep": ",",
"hdrin": false,
"hdrout": "all",
"multi": "mult",
"ret": "\\n",
"temp": "",
"skip": "0",
"strings": true,
"include_empty_strings": "",
"include_null_values": "",
"x": 760,
"y": 280,
"wires": [
[
"9a3547cc81c2d2bb",
"ff9175d01efa5ce4"
]
]
},
{
"id": "9a3547cc81c2d2bb",
"type": "debug",
"z": "b1d8b61d0ed5a5da",
"name": "",
"active": false,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "false",
"statusVal": "",
"statusType": "auto",
"x": 990,
"y": 220,
"wires": []
},
{
"id": "1a270df6276485c4",
"type": "debug",
"z": "b1d8b61d0ed5a5da",
"name": "",
"active": true,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "payload",
"targetType": "msg",
"statusVal": "",
"statusType": "auto",
"x": 1230,
"y": 220,
"wires": []
},
{
"id": "ff9175d01efa5ce4",
"type": "function",
"z": "b1d8b61d0ed5a5da",
"name": "SearchFailureS7",
"func": "let i=0;\nlet ranNum = [];\nranNum = flow.get(\"RandomNum\");\nlet newMsg = [];\n\nwhile (i<ranNum.length){\n\n let n = ranNum[i];\n newMsg[newMsg.length] = {payload: msg.payload[n].col2};\n i = i + 1;\n \n}\n\nreturn newMsg;\n",
"outputs": 1,
"noerr": 0,
"initialize": "",
"finalize": "",
"libs": [],
"x": 1010,
"y": 280,
"wires": [
[
"1a270df6276485c4"
]
]
},
{
"id": "a167b5a81e0b36ba",
"type": "function",
"z": "b1d8b61d0ed5a5da",
"name": "RandomArray",
"func": "const num=[];\nvar i;\n\nfor (i=0; i<3; i++){\n \nnum[i] = Math.floor(Math.random() * 9);\n\n}\n\nrandArray = {payload: num}\n\nreturn randArray;\n",
"outputs": 1,
"noerr": 0,
"initialize": "",
"finalize": "",
"libs": [],
"x": 340,
"y": 400,
"wires": [
[
"c011fa2387db0d18",
"9c400785174973e9"
]
]
},
{
"id": "c011fa2387db0d18",
"type": "debug",
"z": "b1d8b61d0ed5a5da",
"name": "",
"active": true,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "false",
"statusVal": "",
"statusType": "auto",
"x": 530,
"y": 340,
"wires": []
},
{
"id": "9c400785174973e9",
"type": "function",
"z": "b1d8b61d0ed5a5da",
"name": "",
"func": "flow.set(\"RandomNum\",msg.payload);\n",
"outputs": 1,
"noerr": 0,
"initialize": "",
"finalize": "",
"libs": [],
"x": 520,
"y": 400,
"wires": [
[]
]
},
{
"id": "e2d5187d2e705892",
"type": "delay",
"z": "b1d8b61d0ed5a5da",
"name": "Delay 10ms",
"pauseType": "delay",
"timeout": "10",
"timeoutUnits": "milliseconds",
"rate": "1",
"nbRateUnits": "1",
"rateUnits": "second",
"randomFirst": "1",
"randomLast": "5",
"randomUnits": "seconds",
"drop": false,
"allowrate": false,
"outputs": 1,
"x": 330,
"y": 280,
"wires": [
[
"7aa6e0bcbdf67c1c"
]
]
}
]

Answer 1

So, I finally found it. The payload in the while-loop was breaking the loop immediately. So I changed the code in the while-loop using a similar code I found on the net. Now it works.
Old code:
let i=0;
let ranNum = [];
ranNum = flow.get("RandomNum");
let newMsg = [];
while (i<ranNum.length){
let n = ranNum[i];
newMsg[newMsg.length] = {payload: msg.payload[n].col2};
i = i + 1;
}
return newMsg;
New code
let i=0;
let ranNum = [];
ranNum = flow.get("RandomNum");
let newMsg = [];
while (i<ranNum.length){
let n = ranNum[i];
let description = msg.payload[n].col2;
newMsg.push(description);
i = i + 1;
}
msg.payload = newMsg;
return msg;