Webhook Payload Verifier in Elixir/Phoenix

[29hei]

So I’ve been trying to verify notification payload in Elixir/Phoenix.
I read Twich Webhook Guide, what is implied following “notification_bytes” ?

The X-Hub-Signature header is generated by sha256(secret, notification_bytes).

Is this mean “data byte_size” ?
e.g. )

"{"data":[{"to_id":"XXXXX","from_id":"XXXXX","followed_at":"2018-07-15T15:09:18Z"}]}"

I will use Erlang crypto or Plug crypto.

[29hei]

I’ve just solved problem by myself.

I parsed JSON wrong order.