feat: enable OIDC in paperless

hosts/sire/guests/paperless.nix

@@ -2,6 +2,7 @@
   config,
   lib,
   nodes,
+  pkgs,
   ...
 }: let
   sentinelCfg = nodes.sentinel.config;
@@ -47,6 +48,13 @@ in {
     group = "paperless";
   };
 
+  # Mirror the original oauth2 secret
+  age.secrets.paperless-oauth2-client-secret = {
+    inherit (nodes.ward-kanidm.config.age.secrets.kanidm-oauth2-paperless) rekeyFile;
+    mode = "440";
+    group = "paperless";
+  };
+
   environment.persistence."/persist".directories = [
     {
       directory = "/var/lib/paperless";
@@ -56,11 +64,6 @@ in {
     }
   ];
 
-  # TODO: workaround for https://github.com/paperless-ngx/paperless-ngx/discussions/5606
-  systemd.services.paperless-web.script = lib.mkBefore ''
-    mkdir -p /tmp/paperless
-  '';
-
   services.paperless = {
     enable = true;
     address = "0.0.0.0";
@@ -73,6 +76,24 @@ in {
       PAPERLESS_CORS_ALLOWED_HOSTS = "https://${paperlessDomain}";
       PAPERLESS_TRUSTED_PROXIES = sentinelCfg.meta.wireguard.proxy-sentinel.ipv4;
 
+      # Authentication via kanidm
+      PAPERLESS_APPS = "allauth.socialaccount.providers.openid_connect";
+      PAPERLESS_SOCIALACCOUNT_PROVIDERS = builtins.toJSON {
+        openid_connect = {
+          OAUTH_PKCE_ENABLED = "True";
+          APPS = [
+            rec {
+              provider_id = "kanidm";
+              name = "Kanidm";
+              client_id = "paperless";
+              # secret will be added dynamically
+              #secret = "";
+              settings.server_url = "https://${sentinelCfg.networking.providedDomains.kanidm}/oauth2/openid/${client_id}/.well-known/openid-configuration";
+            }
+          ];
+        };
+      };
+
       # Ghostscript is entirely bug-free.
       PAPERLESS_OCR_USER_ARGS = builtins.toJSON {
         continue_on_soft_render_error = true;
@@ -109,6 +130,16 @@ in {
     mode = "0700";
   };
 
+  # Add secret to PAPERLESS_SOCIALACCOUNT_PROVIDERS
+  systemd.services.paperless-web.script = lib.mkBefore ''
+    oidcSecret=$(< ${config.age.secrets.paperless-oauth2-client-secret.path})
+    export PAPERLESS_SOCIALACCOUNT_PROVIDERS=$(
+      ${pkgs.jq}/bin/jq <<< "$PAPERLESS_SOCIALACCOUNT_PROVIDERS" \
+        --compact-output \
+        --arg oidcSecret "$oidcSecret" '.openid_connect.APPS.[0].secret = $oidcSecret'
+    )
+  '';
+
   systemd.services.paperless-backup = let
     cfg = config.systemd.services.paperless-consumer;
   in {

hosts/ward/guests/kanidm.nix

@@ -7,6 +7,12 @@
   sentinelCfg = nodes.sentinel.config;
   kanidmDomain = "auth.${domains.me}";
   kanidmPort = 8300;
+
+  mkRandomSecret = {
+    generator.script = "alnum";
+    mode = "440";
+    group = "kanidm";
+  };
 in {
   meta.wireguard-proxy.sentinel.allowedTCPPorts = [kanidmPort];
 
@@ -22,41 +28,14 @@ in {
     group = "kanidm";
   };
 
-  age.secrets.kanidm-admin-password = {
-    generator.script = "alnum";
-    mode = "440";
-    group = "kanidm";
-  };
+  age.secrets.kanidm-admin-password = mkRandomSecret;
+  age.secrets.kanidm-idm-admin-password = mkRandomSecret;
 
-  age.secrets.kanidm-idm-admin-password = {
-    generator.script = "alnum";
-    mode = "440";
-    group = "kanidm";
-  };
-
-  age.secrets.kanidm-oauth2-immich = {
-    generator.script = "alnum";
-    mode = "440";
-    group = "kanidm";
-  };
-
-  age.secrets.kanidm-oauth2-grafana = {
-    generator.script = "alnum";
-    mode = "440";
-    group = "kanidm";
-  };
-
-  age.secrets.kanidm-oauth2-forgejo = {
-    generator.script = "alnum";
-    mode = "440";
-    group = "kanidm";
-  };
-
-  age.secrets.kanidm-oauth2-web-sentinel = {
-    generator.script = "alnum";
-    mode = "440";
-    group = "kanidm";
-  };
+  age.secrets.kanidm-oauth2-forgejo = mkRandomSecret;
+  age.secrets.kanidm-oauth2-grafana = mkRandomSecret;
+  age.secrets.kanidm-oauth2-immich = mkRandomSecret;
+  age.secrets.kanidm-oauth2-paperless = mkRandomSecret;
+  age.secrets.kanidm-oauth2-web-sentinel = mkRandomSecret;
 
   nodes.sentinel = {
     networking.providedDomains.kanidm = kanidmDomain;
@@ -130,6 +109,16 @@ in {
         scopeMaps."immich.access" = ["openid" "email" "profile"];
       };
 
+      # Paperless
+      groups."paperless.access" = {};
+      systems.oauth2.paperless = {
+        displayName = "Paperless";
+        originUrl = "https://${sentinelCfg.networking.providedDomains.paperless}/";
+        basicSecretFile = config.age.secrets.kanidm-oauth2-paperless.path;
+        preferShortUsername = true;
+        scopeMaps."paperless.access" = ["openid" "email" "profile"];
+      };
+
       # Grafana
       groups."grafana.access" = {};
       groups."grafana.editors" = {};

secrets/generated/ward-kanidm/kanidm-oauth2-paperless.age

@@ -0,0 +1,11 @@
+age-encryption.org/v1
+-> X25519 hzkY1fcGtdk9GFrYskb/0fFAAgD4hAwtyd23quaPCD8
+akEojVvE36WwAGv9aZFWZLbBvhIeZjOaSncWtVfwAn4
+-> piv-p256 xqSe8Q A2icKgRBVKO9BjUUSNDLds1Eq+DL1+wfLy0r4U1Q8YNP
+630Lq8Y4XgZcDFGa4deEHGXTE3qkxPHgev7i4mKtM+o
+-> dI-grease _8iXML(
+22JTt6b8FjyMsaFuddGHWGgurfZBbpMTUhIHzTn7RC9/RxQblyAWinMlZjcDyGAP
++wQYeeqG0aIyFgasJLMuu1IRBQaEmRKVTiGRgh7Sm5FHnF0u6aAu0pj/iOX2xbw
+--- 04iwf902sMdNHLYmynps8wNLhwrYNoK0w99KdPz7SO0
+º¼Ãyež€=$¿qÄuÕ°M·/ùú\�àâƒûû}Žu4ÔÈšj¿YŸ…Tõo,_µ
lOí fS24�•Ãþù¬SÁ
+T;7—pÍ{6²š

secrets/rekeyed/sire-paperless/07944f6e713f88e307284d3d01662208-paperless-oauth2-client-secret.age

@@ -0,0 +1,7 @@
+age-encryption.org/v1
+-> ssh-ed25519 vqFVQw q5QZqkI20/kI0xMQ3sRewA122Cm13qfE0LhuFr9K6g8
+0qWz+XFjeyiNnGlAfffoL/iZdwS9NzXOYyl7FmUY2hI
+-> 2FQ(N@-grease
+
+--- AVDxWkWApQ6FCrAwGvzg9u3RklcWZeQFg2iqqqeNQ2E
+Ê^Ç|´^ „²1»D¼ä©"®Zм/Ç`JàÛ¯ãã€òu'ñPv‘Î
U,)Ew¤\§ä¾ä¼gó‹‚ÈdAþ/ Má€X@2›