Looping through an object by incrementing an object name

General
1

I get a JSON variable with sequentially numbered objects, and need to loop through it to pull out some data.

In the past, I've had success with ["name" + i], but NR is calling it an unknown object in this case.

Anyone have an idea how I can iterate through this?



var targets = flow.get('targets');
var unitCount = Object.keys(targets).length;
var position = " ";


for (i = 1; i < unitCount; i++) {
    position = 'xds' + i;
    msg.ip = targets.position.IP;
    msg.label = targets.position.Unit;
    msg.position = position;
    msg.index = i;
    node.send(msg);
}

msg.targets = targets;
msg.vars = targets.length;
return msg;

This is the JSON data entered to the flow variable:

{
    "xds1": {
        "IP": "10.X.X.X",
        "Unit": "R1"
    },
    "xds2": {
        "IP": "10.X.X.X",
        "Unit": "S1"
    },
    "xds3": {
        "IP": "10.X.X.X",
        "Unit": "S2"
    },
    "xds4": {
        "IP": "10.X.X.X",
        "Unit": "A1"
    },
    "xds5": {
        "IP": "10.X.X.X",
        "Unit": "A2"
    }
}

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2

As an example of this working, though in different use, I've used the "string + i" method to create new strings on each iteration, using it to then get a flow variable. I didn't expect it to work because it never worked in other languages I've used, but it did here, so I was hoping to get away with it on the JSON object also...

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3

Look at the Object functions keys, values and entries for iterating object properties.

MDN is super helpful here as it has interactive examples you can try out in the browser

4

Awesome, thanks Steve, will try.

5

Ok, that got me on the right path, though initially, I couldn't get it to iterate into the subkeys(?). With a boatload of trial and error, then stumbling across something on Stack Exch, I'm able to iterate through.

Posting for anyone that finds this and needs a solution.

var targets = flow.get('targets');
var keys = Object.keys(targets);
var data = {}

for(var i = 0; i < keys.length;i++){
    data = targets[keys[i]]
    msg.test = data.IP;
    msg.test2 = data.Unit;
    node.send(msg);
}
6

Or you could have used a split node and a change node to iterate over the object and manipulate the msg properties.
e.g.

[{"id":"07a8af26d48806c8","type":"inject","z":"d1395164b4eec73e","name":"","props":[{"p":"payload"},{"p":"topic","vt":"str"}],"repeat":"","crontab":"","once":false,"onceDelay":0.1,"topic":"","payload":"{     \"xds1\": {         \"IP\": \"10.X.X.X\",         \"Unit\": \"R1\"     },     \"xds2\": {         \"IP\": \"10.X.X.X\",         \"Unit\": \"S1\"     },     \"xds3\": {         \"IP\": \"10.X.X.X\",         \"Unit\": \"S2\"     },     \"xds4\": {         \"IP\": \"10.X.X.X\",         \"Unit\": \"A1\"     },     \"xds5\": {         \"IP\": \"10.X.X.X\",         \"Unit\": \"A2\"     } }","payloadType":"json","x":570,"y":5200,"wires":[["b7db0f3b0e1dd5f0"]]},{"id":"b7db0f3b0e1dd5f0","type":"split","z":"d1395164b4eec73e","name":"","splt":"\\n","spltType":"str","arraySplt":1,"arraySpltType":"len","stream":false,"addname":"","x":710,"y":5200,"wires":[["2753693fbeb19e3b"]]},{"id":"2753693fbeb19e3b","type":"change","z":"d1395164b4eec73e","name":"","rules":[{"t":"set","p":"test1","pt":"msg","to":"payload.IP","tot":"msg"},{"t":"set","p":"test2","pt":"msg","to":"payload.Unit","tot":"msg"}],"action":"","property":"","from":"","to":"","reg":false,"x":860,"y":5200,"wires":[["3552c41dbd6cc181"]]},{"id":"3552c41dbd6cc181","type":"debug","z":"d1395164b4eec73e","name":"debug 2476","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"true","targetType":"full","statusVal":"","statusType":"auto","x":1050,"y":5200,"wires":[]}]
7

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