Hi Ceremona, welcome to the forum!

I often link people to this post for the format of the publisher's output, which is what the HTTP Receiver is made to work with (though any client could send such HTTP messages, of course):
https://forum.infiniteautomation.com/topic/2187/how-to-use-publishers-http-sender/3

Outgoing HTTP receiver messages are not quite the same formatting, as was discussed in this thread:
https://forum.infiniteautomation.com/topic/2854/http-receiver-set-point-name

For the HTTP JSON receiver, you may find the last post in this thread answers the question:
https://forum.infiniteautomation.com/topic/4057/how-to-set-a-value-using-http/9

The HTTP JSON receiver does not currently support settable points, so perhaps there is a useful feature to be added there.

If you look at the '?' there is a full blown user help for how to utilise these sources.

As can be read, the url you need to post to is http://[mangodomain|localhost]/httpds

Anyway, you see that set point url I'm pointing to?
EDIT: Sorry I meant to mean device white list, I was pointing at the wrong textbox!
You set that as your reference so it will land (the data) in this datasource.
the parameter being __device

Here's a snippet:

var _URL="http://ipAddressHere/httpds?__device=DEMO&QUANTUMM1="+pt*.value+'@'+pt*.time;
       httpReq(_URL,"post",res,{'Content-Type':'application/x-www-form-urlencoded'},{});

Where in this case QUANTUMM1 is my point identifier in the data point in the data source itself.

The format as you can see in the code (1 of the allowed formats at least, read the datasource help for the others) is "+pt*.value+'@'+pt*.time
So value first, separated by an '@' then a timestamp. NOTE This format I believe is the publisher set format for the set format option of this datasource so you can use a mango publisher to flick data via an http publisher to a mango http receiver datasource.

So as a recap:

params: __device=[setPointUrl]
&httpParameterName=[value]@[Timestamp]

url: mangoUrl/httpds

You can test by clicking on the 'Listen for HTTP data' button to ascertain if your values are coming through.
Any further confusion, we're all here to help

Fox