Where to find the eventSub message id header?

BarryCarlyon · May 22, 2021, 1:40pm

That looks like the headers returned on a outbound fetch request

Not on an inbound request from Twitch to you. Which most likely would be part of express.

BarryCarlyon/twitch_misc/blob/main/eventsub/handlers/nodejs/receive.js#L45


// Express allows whats called middle ware
// it runs before (or after) other parts of the route runs
app.use(bodyParser.json({
    verify: function(req, res, buf, encoding) {
        // is there a hub to verify against
        req.twitch_hub = false;
        if (req.headers && req.headers.hasOwnProperty('twitch-eventsub-message-signature')) {
            req.twitch_hub = true;

            // id for dedupe
            var id = req.headers['twitch-eventsub-message-id'];
            // check age
            var timestamp = req.headers['twitch-eventsub-message-timestamp'];

            var xHub = req.headers['twitch-eventsub-message-signature'].split('=');

            // you could do
            // req.twitch_hex = crypto.createHmac(xHub[0], config.hook_secret)
            // but we know Twitch always uses sha256
            req.twitch_hex = crypto.createHmac('sha256', config.hook_secret)
                .update(id + timestamp + buf)

if you are using express to recieve webhooks