Also to avoid fun™ with encoding:
https://dev.twitch.tv/docs/api/webhooks-reference/#example-of-webhook-flow
Suggests:
curl -H ‘Client-ID: uo6dggojyb8d6soh92zknwmi5ej1q2’
-H ‘Content-Type: application/json’
-X POST -d ‘{“hub.mode”:“subscribe”,
“hub.topic”:“https://api.twitch.tv/helix/users/follows?to_id=1337”,
“hub.callback”:“https://yourwebsite.com/path/to/callback/handler”,
“hub.lease_seconds”:“864000”,
“hub.secret”: s3cRe7}’
https://api.twitch.tv/helix/webhooks/hub
So:
request({method: "POST’, url: ‘https://api.twitch.tv/helix/webhooks/hub’, json: true, body: {“hub.mode”:“subscribe”,
“hub.topic”:“https://api.twitch.tv/helix/users/follows?first=1&to_id=1337”,
“hub.callback”:“https://yourwebsite.com/path/to/callback/handler”,
“hub.lease_seconds”:“864000”,
“hub.secret”: s3cRe7}, headers: { Client-ID: ‘xxxxx’ }
Should do the trick, not tested off the top of my head™