Converting *entire* msg object to JSON

General
1

I'm probably overlooking something simple, but how would one go about converting an entire msg object to JSON. In my specific use case, I will be packaging that data into a payload to be sent over a TCP connection between Node-RED instances.

My specific use case at this time is to get messages from distributed instances to a firewalled instance that can talk to an SMTP relay for notifications. I have that working wonderfully using change nodes to explicitly package the traffic I'm wanting to send, with a corresponding unpack operation on the other end, but I'd like to do it a lot more "generically" in the future.

2

You will need to be aware of what is in the content of the msg object. Some things cannot be serialised (e.g. functions).

Then you can use a function node with JavaScript standard JSON object which has a serialise capability. This turns a JavaScript object into a string which you can pass and then parse at the other end.

JSON.parse() reverses the serialise.

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3

Worked beautifully. In case someone stumbles across this, my flow was as follows:

Outbound: A function node with

var payload = JSON.stringify(msg);
node.send({payload});

going into a TCP out node set to connect to a specific port and close connection after each message.

Inbound: A TCP In node set to listen on the same specified port and output a single string, which then goes to a function node containing:

msg = JSON.parse(msg.payload);
return msg;

Many thanks to TotallyInformation for answering in a way that put me on the right path but was just far enough from hand-holding to make me have to bash my head against it to learn a bit.

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