Solved: Could not authenticate you from OpenIDConnect because "Undefined method 'with indifferent access' for an instance of string".

[BartschLabs]

I couldn't find an answer for this in the Manyfold documentation or in Discussions or Issues, so I thought I'd add it.

For anybody else getting this error after hitting the button to sign in with OIDC:

Could not authenticate you from OpenIDConnect because "Undefined method 'with indifferent access' for an instance of string".

Solution: The error was caused by the OIDC_ISSUER environment variable being set to my OIDC provider's Authorization URL instead of just the base URL of my OIDC provider.

Incorrect:
OIDC_ISSUER=https://id.my-domain.com/authorize
Correct:
OIDC_ISSUER=https://id.my-domain.com

Suggestion: Perhaps the Manyfold documentation for OIDC_ISSUER could be updated to include a note that some OIDC providers don't mention an issuer string or URL, but it's simply the base URL for your OIDC provider.

I have to applaud the Manyfold team for implementing the OIDC setup in such a simple way. It's basically three variables -- OIDC_CLIENT_ID, OIDC_CLIENT_SECRET, and OIDC_ISSUER -- with a mandatory one more -- MULTIUSER -- and two others that I think are also mandatory -- PUBLIC_HOSTNAME, and HTTPS_ONLY.

If you're interested in more detail and how I arrived at the answer:

From my basic googling, it appeared that this error typically indicates that the application is expecting a JSON object (or hash/dictionary) from the OIDC Provider's user information endpoint, but is receiving a raw string instead.

I could login OK with the local administrator account.

My Setup:

Pocket ID is my OIDC provider. Pocket ID has been working well with Beszel and Forgejo.

Caddy is my reverse proxy.

Manyfold docker image: lscr.io/linuxserver/manyfold:latest

My Manyfold OIDC-related environment variables:
MULTIUSER=enabled
HTTPS_ONLY=enabled
PUBLIC_HOSTNAME=manyfold.my-domain.com
PUBLIC_PORT=443
OIDC_CLIENT_ID=my-client-ID
OIDC_CLIENT_SECRET=my-client-secret
OIDC_ISSUER=https://id.my-domain.com/authorize
OIDC_NAME="Pocket ID"

Pocket ID Userinfo URL: https://id.my-domain.com/api/oidc/userinfo
Pocket ID Callback URL for Manyfold: https://manyfold.my-domain.com/users/auth/openid_connect/callback

I don't believe that Pocket ID offers anything in the way of manipulating the output of the userinfo endpoint, but that wasn't the cause at all.

From some more googling I found that somebody had solved the same problem with Pocket ID and MeshCentral.

[Floppy]

That's great, thank you, I'll try to make the documentation clearer on that!