About msg.payload.xxxx.x?

[jlian168]

Dear All :

Look at Pic red circle ?
Where is the msg.payload.xxxx.x?

Thank u.

[Colin]

What pic?

[knolleary]

Hi @jlian168

I am not sure what you are asking here. Can you explain a bit more about what you want to know?

[jlian168]

Dear knolleary :

Most I see msg. is msg.payload,
But in here is msg.payload.acceleration.x,
So I dont where it hv been define?
So my most problem is the object msg has how many msg.xxxx.xxxx.x name?

My english is poor, So hope u can understand my question...
Thank u very much.

[knolleary]

Hi @jlian168

It looks like you are using the SenseHAT node. If you read the help for that node, you will see if describes the format of the msg.payload it sends.

In this case, it sets msg.payload to an Object like:

msg.payload = {
   acceleration: {
      x: 1,
      y: 2,
      z: 3
  }
}

If you were to add a Debug node next to the SenseHat node, configured to show you msg.payload, you would see the full structure of the payload object.

[jlian168]

Dear knolleary :

ok, I see.

Thanks for ur help, Thank u very much.

[jlian168]

Dear Sir :

Another about msg.xxx? At pic red circle, The msg.headers Where it is from?

Thank u.

[knolleary]

Every node uses different message properties. They all provide help in the Help Sidebar that describes what message properties they use.

That is a Change node that is setting msg.headers.

That is probably being passed to an HTTP Response or HTTP Request node that uses that property to set it's headers.

[jlian168]

Dear knolleary :

ok.

Thank u,