fix: re-enable PKCE by default

[edward-ly]

Resolves #807.

[edward-ly]

Hmm, all of the integration tests on the NC master branch are failing. I can't really tell from the logs where exactly the problem is coming from, though.

[julien-nc]

I fixed the CI in another PR that was not merged yet. It's now fixed. I rebased your branch on main and pushed again. Should be fine now.

[julien-nc]

Since it's now enabled by default, we could check if the provider supports our code challenge method (for safety). This information can be found in the discovery. S256 (the method we use) should be included in the code_challenge_methods_supported array in the provider's discovery.
Here is what's inside a classic Keycloak's discovery:

"code_challenge_methods_supported": [
  "plain",
  "S256"
],

So I think we should use PKCE only if it is enabled in NC's config AND the provider supports S256.

Wdyt?

[edward-ly]

Makes sense to me, will take a look when I have the chance to get to it.

[julien-nc]

Nice!
Can you rebase your branch on main? Since there are no conflicts, it makes the history cleaner and easier to read.

[edward-ly]

Nice! Can you rebase your branch on main? Since there are no conflicts, it makes the history cleaner and easier to read.

Ah, good idea, this should do it, I think.

[julien-nc]

👍