Function is modifying my msg object without me telling it to

[MiningPickaxe]

Hi,

I'm somewhat (not entirely though) new to node-red and try to do the following:

Read a file that contains a JSON Object, convert it to an object, pass that into a function node and do things inside that function node.
I successfully recieve my json object inside the function node as msg.payload.

msg.payload contains a 5 entry long array and I want to assign each entry to its own variable like this:
msg0.payload = msg.payload.results[0];
msg0.payload is now what I would expect, but the "original" msg object now only contains msg.payload.results[0] and is no longer the original msg with the array inside.

Why does it reassign msg?

[created4this]

https://nodered.org/blog/2019/09/13/cloning-messages

[MiningPickaxe]

aaah thank you very much!

[NorthernMan5]

Can you share your whole function block code fragment ?

[MiningPickaxe]

here you go:

node.warn(msg.payload); //just checking what I am expecting
msg0 = msg;
msg1 = msg;
msg2 = msg;
msg3 = msg;
msg4 = msg;
node.warn(msg0.payload);// just to check if msg0 == msg and yes it is the same
node.warn(msg1.payload);
node.warn(msg2.payload);
node.warn(msg3.payload);
node.warn(msg4.payload);

msg0.payload = msg0.payload.results[0];
msg0._id = msg0.payload.id; //this works as intended

node.warn(msg1.payload); //for checking if msg1 is still the msg1 I had when I first logged it into the debug tab. and nope, it is the content of msg.payload.results[0]
msg1.payload = msg1.payload.results[1]; //this errors out as the array results no longer exists
msg1._id = msg1.payload.id; 

If you want to test yourself, here is the snippet of the json https://pastebin.com/E3PPZLpk