Syntax for JSON 'payload' in Facebook FB.api post

Question

I'm trying to add users to a Custom Audience in Facebook, and I believe I have bungled the payload piece of the request below.

The error returned is:

(#100) Missing required parameter: payload 

For reference, I'm generating the hash using Crypto-JS. Here's the code I tried:

var payload = { "payload": [{ "schema": "EMAIL_SHA256", "data": [hash] }]};

FB.api('/000000000/users', 'post', payload, function (response) {
                if (response && !response.error) {
                    alert("This worked");
                } else {
                    alert(response.error.message);
                }});

The FB.api documentation shows that it expects 'payload' as a JSON object (https://developers.facebook.com/docs/marketing-api/custom-audience-targeting/v2.3#add). I just haven't been able to figure out the correct syntax yet. The example in the Facebook API documentation shows the following:

payload = {"schema":"EMAIL_SHA256","data":["HASH", "HASH", "HASH" ]}

Here's what I have so far (not working):

var payload = { "payload": [{ "schema": "EMAIL_SHA256", "data": [hash] }]};

Can anyone assist with the syntax? I've found plenty of examples of JSON objects and arrays, but I haven't seen anything that matches this format:

payload = {"schema":"EMAIL_SHA256","data":["HASH", "HASH", "HASH" ]}

Answer 1

For the benefit of any other JS/JSON novices, I finally figured it out after more experimentation:

 var payload = { "payload": { "schema": "EMAIL_SHA256", "data": [hash] } };