Apple OAuth2 example doesn't work

Prerequisites

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Fastify version

4.26.1

Plugin version

7.8.0

Node.js version

v20.6.1

Operating system

Windows

Operating system version (i.e. 20.04, 11.3, 10)

10

Description

I created the issue, so that it clarifies the issue or helps other people.

I had to make changes to make the example work. examples/apple.js

Explicitly setting scope to empty (otherwise undefined error) scope: [], //'name', 'email' , when I set scope apple returns POST form-urlencoded. That is documented in the example and Github issues. It might be nice to provide an example for that case as well.

const { code, state, error, user } = request.query instead of request.body

Wher does Error.CancelledAuth comes from? It is undefined so it has wrong logic when error is also undefined.

The part I didn't understand:
request.cookies['oauth2-redirect-state'] this is empty, however the cookie is set in browser dev tools.

Readme states, "Since v7.2.0, @fastify/oauth2 requires the use of cookies to securely implement the OAuth2 exchange." It is after this example is updated on the repo.

Steps to Reproduce

Create a new project npm init fastify and try examples/apple.js example

Expected Behavior

No response

I've no good experience on implementing Apple login. So, I can't really help much.

A PR to fix the example would be amazing.

Hi @mcollina, thanks for the reply. Do you have any idea why oauth2-redirect-state cookie is empty?

Plugin checks this at

fastify-oauth2/index.js

Line 26 in f9c4a5c

function defaultCheckStateFunction (request, callback) {

when I'm using getAccessTokenFromAuthorizationCodeFlow function

If I can fix it, I can contribute a clean PR.

Regards,
Fatih

A cookie is empty if it's not set or the origin is different. In this case 127.0.0.0 and localhost are not equivalent.

How do you access the server?

There is frontend server vite proxying from dev.example.com:3001 to fastify localhost:3000. When I check the cookies from devtools->Application it is there. Since it is stuck on /login/apple/callback GET route, I would assume it is there. Any ideas to check/debug, or to give more information to you?

fastify-oauth2/examples/apple.js

Line 44 in f9c4a5c

fastify.get('/login/apple/callback', function (request, reply) {

Here maybe post