How to use with Authelia for OpenID Connect authentication?

[poperigby]

Gatus keeps crashing every time I try to start it, with OIDC configured.

Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.LoadConfiguration] Reading configuration from configFile=/nix/store/7bdksxcybszqbzlcrgz3qy9gshj5fnvk-gatus.yaml
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateAlertingConfig] Alerting is not configured
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateSecurityConfig] Basic security configuration has been validated
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validating endpoint 'Nextcloud'
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validating endpoint 'Authelia'
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validating endpoint 'Mealie'
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validating endpoint 'Miniflux'
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validating endpoint 'LLDAP'
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validating endpoint 'Sonarr'
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validating endpoint 'Radarr'
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validating endpoint 'Prowlarr'
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validating endpoint 'PrusaLink'
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validating endpoint 'Jellyfin'
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validated 10 endpoints
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [config.validateEndpointsConfig] Validated 0 external endpoints
Jun 13 19:06:23 haddock gatus[389657]: 2024/06/13 19:06:23 [store.Initialize] Creating storage provider of type=memory
Jun 13 19:06:23 haddock gatus[389657]: panic: 404 Not Found: 404 Not Found
Jun 13 19:06:23 haddock gatus[389657]: goroutine 50 [running]:
Jun 13 19:06:23 haddock gatus[389657]: github.com/TwiN/gatus/v5/api.(*API).createRouter(0xc000148f60?, 0xc000729860)
Jun 13 19:06:23 haddock gatus[389657]:         github.com/TwiN/gatus/v5/api/api.go:113 +0xd36
Jun 13 19:06:23 haddock gatus[389657]: github.com/TwiN/gatus/v5/api.New(0xc000729860)
Jun 13 19:06:23 haddock gatus[389657]:         github.com/TwiN/gatus/v5/api/api.go:34 +0x106
Jun 13 19:06:23 haddock gatus[389657]: github.com/TwiN/gatus/v5/controller.Handle(0xc000729860)
Jun 13 19:06:23 haddock gatus[389657]:         github.com/TwiN/gatus/v5/controller/controller.go:19 +0x27
Jun 13 19:06:23 haddock gatus[389657]: created by main.start in goroutine 1
Jun 13 19:06:23 haddock gatus[389657]:         github.com/TwiN/gatus/v5/main.go:44 +0x56
Jun 13 19:06:23 haddock systemd[1]: gatus.service: Main process exited, code=exited, status=2/INVALIDARGUMENT

Here's my Authelia configuration for Gatus:

identity_providers:
  oidc:
    clients:
      - client_id: {{ secret "/run/secrets/gatus-oidc-client-id_authelia" | mindent 10 "|" | msquote }}
        client_name: 'Gatus'
        client_secret: {{ secret "/run/secrets/gatus-oidc-client-secret_authelia" | mindent 10 "|" | msquote }}
        public: false
        authorization_policy: 'one_factor'
        redirect_uris:
          - 'https://status.haddock.cc/authorization-code/callback'
        scopes:
          - 'openid'

Here's my Gatus OIDC configuration:

security:
  oidc:
    client-id: $OIDC_CLIENT_ID
    client-secret: $OIDC_CLIENT_SECRET
    issuer-url: https://auth.haddock.cc/.well-known/openid-configuration
    redirect-url: https://status.haddock.cc/authorization-code/callback
    scopes:
    - openid

Gatus version: 5.11.0
Authelia version: 4.38.8

[poperigby]

Figured it out. You have to use just https://auth.haddock.cc without the .well-known/openid-configuration. Seems that gets added automatically.