Better way to assign a message payload than how I'm doing it?

Third party integrations Node-RED
1

I am using a pretty simple function node to, based on a zone change, output a message to send to my Sonos using the tts-ultimate node. I am not proficient at JS. This is how I’m doing it, but maybe it’d be better to set up some kind of array? If so, how would that look?

if (msg.payload === "home") {
    msg.payload = "Tammy has arrived home";
} else {
    msg.payload = "Tammy has arrived at work";
}
return msg;
2

I do not think that can be done much better with that notation type.
There might be another notation type with : ? and other characters that are shorter in characters, but not more efficient in the execution and that one can be a bit more tricky to read for others.

3

Not pretty but it’s more compact.

msg.payload = "Tammy has arrived at " + msg.payload;
msg.payload = msg.payload.replace("at home", "home");

return msg;

I don’t have any way of testing it now but perhaps you could also use

msg.payload = ("Tammy has arrived at " + msg.payload).replace("at home", "home");

return msg;

But I’m not sure that is valid syntax.

4

Thanks for the replies. Actually wrote a method to handle it easier. Just need to keep adding to the array.

let tamZone=[
    ["salon","Tammy has arrived at Evelia's Salon"],
    ["home","Tammy has arrived home"],
    ["swpg","Tammy has arrived at work"]
]

let zlen = tamZone.length;

for (let i = 0; i < zlen; i++) {
    node.warn(tamZone[i][1]);
    node.warn(msg.payload);
    if (tamZone[i][0] == msg.payload) {
      msg.payload = tamZone[i][1];
    }
}
return msg;
5

In that case

let tamZone={
    salon: "Tammy has arrived at Evelia's Salon",
    home: "Tammy has arrived home",
    swpg: "Tammy has arrived at work"
}

mag.payload = tamZone[msg.payload];

return msg
6

Nice. Much more elegant, but I thought that JS didn’t support associated arrays?

I pulled this from w3schools.com:

Many programming languages support arrays with named indexes.

Arrays with named indexes are called associative arrays (or hashes).

JavaScript does not support arrays with named indexes.

In JavaScript, arrays always use numbered indexes.
7

I haven’t been able to try it since I have been on vacation but it should work.
Here is about associative arrays (objects is probably the correct name) in JavaScript.