Added role claim to Audiobookshelf's OIDC client config

modules/services/audiobookshelf.nix

@@ -6,6 +6,8 @@ let
   contracts = pkgs.callPackage ../contracts {};
 
   fqdn = "${cfg.subdomain}.${cfg.domain}";
+
+  roleClaim = "audiobookshelf_groups";
 in
 {
   options.shb.audiobookshelf = {
@@ -173,17 +175,35 @@ in
       '';
     };
 
+
+    shb.authelia.extraDefinitions = {
+      user_attributes.${roleClaim}.expression = 
+          ''"${cfg.sso.adminUserGroup}" in groups ? ["admin"] : ("${cfg.sso.userGroup}" in groups ? ["user"] : [""])'';
+    };
+
+    shb.authelia.extraOidcClaimsPolicies.${roleClaim} = {
+      custom_claims = {
+        "${roleClaim}" = {};
+      };
+    };
+
+    shb.authelia.extraOidcScopes."${roleClaim}" = {
+      claims = [ "${roleClaim}" ];
+    };
+
     shb.authelia.oidcClients = lib.lists.optionals cfg.sso.enable [
       {
         client_id = cfg.sso.clientID;
         client_name = "Audiobookshelf";
         client_secret.source = cfg.sso.sharedSecretForAuthelia.result.path;
+        claims_policy = "${roleClaim}";
         public = false;
         authorization_policy = cfg.sso.authorization_policy;
         redirect_uris = [ 
           "https://${cfg.subdomain}.${cfg.domain}/auth/openid/callback" 
           "https://${cfg.subdomain}.${cfg.domain}/auth/openid/mobile-redirect" 
         ];
+        scopes = [ "openid" "profile" "email" "groups" "${roleClaim}" ];
         require_pkce = true;
         pkce_challenge_method = "S256";
         userinfo_signed_response_alg = "none";

modules/services/audiobookshelf/docs/default.md

@@ -0,0 +1,63 @@
+# Audiobookshelf Service {#services-audiobookshelf}
+
+Defined in [`/modules/services/audiobookshelf.nix`](@REPO@/modules/services/audiobookshelf.nix).
+
+This NixOS module is a service that sets up a [Audiobookshelf](https://www.audiobookshelf.org/) instance.
+
+## Features {#services-audiobookshelf-features}
+
+- Declarative selection of listening port.
+- Access through [subdomain](#services-audiobookshelf-options-shb.audiobookshelf.subdomain) using reverse proxy. [Manual](#services-audiobookshelf-usage-configuration).
+- Access through [HTTPS](#services-audiobookshelf-options-shb.audiobookshelf.ssl) using reverse proxy. [Manual](#services-audiobookshelf-usage-https).
+- Declarative [SSO](#services-audiobookshelf-options-shb.audiobookshelf.sso) configuration (Manual setup in app required). [Manual](#services-audiobookshelf-usage-sso).
+- [Backup](#services-audiobookshelf-options-shb.audiobookshelf.backup) through the [backup block](./blocks-backup.html). [Manual](#services-audiobookshelf-usage-backup).
+
+## Usage {#services-audiobookshelf-usage}
+
+### Login
+
+Upon first login, Audiobookshelf will ask you to create a root user. This user will be used to
+set up [SSO]{#services-audiobookshelf-usage-sso}, or to provision admin privileges to other users.
+
+### With SSO Support {#services-audiobookshelf-usage-sso}
+
+:::: {.note}
+Some manual setup in the app is required.
+::::
+
+We will use the [SSO block][] provided by Self Host Blocks.
+Assuming it [has been set already][SSO block setup], add the following configuration:
+
+[SSO block]: blocks-sso.html
+[SSO block setup]: blocks-sso.html#blocks-sso-global-setup
+
+```nix
+shb.audiobookshelf.sso = {
+  enable = true;
+  endpoint = "https://${config.shb.authelia.subdomain}.${config.shb.authelia.domain}";
+
+  secretFile = <path/to/oidcJellyfinSharedSecret>;
+  secretFileForAuthelia = <path/to/oidcJellyfinSharedSecret>;
+};
+```
+
+The `shb.audiobookshelf.sso.secretFile` and `shb.audiobookshelf.sso.secretFileForAuthelia` options
+must have the same content. The former is a file that must be owned by the `audiobookshelf` user while
+the latter must be owned by the `authelia` user. I want to avoid needing to define the same secret
+twice with a future secrets SHB block.
+
+In the Audiobookshelf app, you can now log in with your Audiobookshelf root user and go to
+"Settings->Authentication", and then enable "OpenID Connect Authentication" and enter your
+"Issuer URL" (e.g. `https://auth.example.com`). Then click the "Auto-populate" button. Next, paste
+in the client secret (from `secrets.yaml`). Then set up "Client ID" to be `audiobookshelf`. Make
+sure to also select `None` in "Subfolder for Redirect URLs". Then make sure to tick "Auto Register".
+You can also tick "Auto Launch" to make Audiobookshelf automatically redirect users to the SSO
+sign-in page instead. This can later be circumvented by accessing
+`https://<your-domain>/login?autoLaunch=0`, if you're having SSO issues.
+Finally, set "Group Claim" to `audiobookshelf_groups`. This enables Audiobookshelf to allow access
+only to users belonging to `userGroup` (default `audiobookshelf_user`), and to grant admin
+privileges to members of `adminUserGroup` (default `audiobookshelf_admin`).
+
+Save the settings and restart the Audiobookshelf service (`systemctl restart audiobookshelf.service`).
+
+You should now be able to log in with users belonging to either of the aforementioned allowed groups.