From e962d4c574dee34531e3b936b2ca5042d1aada4c Mon Sep 17 00:00:00 2001
From: Bruno BELANYI <bruno@belanyi.fr>
Date: Sat, 25 Sep 2021 16:01:41 +0200
Subject: [PATCH] modules: services: nginx: sso: use runtime secrets

---
 modules/services/nginx/default.nix     |  4 ++
 modules/services/nginx/sso/default.nix | 89 ++++++++++++++++++++++++++
 2 files changed, 93 insertions(+)
 create mode 100644 modules/services/nginx/sso/default.nix

diff --git a/modules/services/nginx/default.nix b/modules/services/nginx/default.nix
index d5d8b31..492f6c8 100644
--- a/modules/services/nginx/default.nix
+++ b/modules/services/nginx/default.nix
@@ -57,6 +57,10 @@ let
   };
 in
 {
+  imports = [
+    ./sso
+  ];
+
   options.my.services.nginx = with lib; {
     enable = mkEnableOption "Nginx";
 
diff --git a/modules/services/nginx/sso/default.nix b/modules/services/nginx/sso/default.nix
new file mode 100644
index 0000000..987e926
--- /dev/null
+++ b/modules/services/nginx/sso/default.nix
@@ -0,0 +1,89 @@
+# I must override the module to allow having runtime secrets
+{ config, lib, pkgs, utils, ... }:
+let
+  cfg = config.services.nginx.sso;
+  pkg = lib.getBin cfg.package;
+  confPath = "/var/lib/nginx-sso/config.json";
+in
+{
+  disabledModules = [ "services/security/nginx-sso.nix" ];
+
+
+  options.services.nginx.sso = with lib; {
+    enable = mkEnableOption "nginx-sso service";
+
+    package = mkOption {
+      type = types.package;
+      default = pkgs.nginx-sso;
+      defaultText = "pkgs.nginx-sso";
+      description = ''
+        The nginx-sso package that should be used.
+      '';
+    };
+
+    configuration = mkOption {
+      type = types.attrsOf types.unspecified;
+      default = { };
+      example = literalExample ''
+        {
+          listen = { addr = "127.0.0.1"; port = 8080; };
+
+          providers.token.tokens = {
+            myuser = "MyToken";
+          };
+
+          acl = {
+            rule_sets = [
+              {
+                rules = [ { field = "x-application"; equals = "MyApp"; } ];
+                allow = [ "myuser" ];
+              }
+            ];
+          };
+        }
+      '';
+      description = ''
+        nginx-sso configuration
+        (<link xlink:href="https://github.com/Luzifer/nginx-sso/wiki/Main-Configuration">documentation</link>)
+        as a Nix attribute set.
+      '';
+    };
+  };
+
+  config = lib.mkIf cfg.enable {
+    systemd.services.nginx-sso = {
+      description = "Nginx SSO Backend";
+      after = [ "network.target" ];
+      wantedBy = [ "multi-user.target" ];
+      serviceConfig = {
+        StateDirectory = "nginx-sso";
+        WorkingDirectory = "/var/lib/nginx-sso";
+        # The files to be merged might not have the correct permissions
+        ExecStartPre = ''+${pkgs.writeScript "merge-nginx-sso-config" ''
+          #!${pkgs.bash}/bin/bash
+          ${utils.genJqSecretsReplacementSnippet cfg.configuration confPath}
+
+          # Fix permissions
+          chown nginx-sso:nginx-sso ${confPath}
+          chmod 0600 ${confPath}
+        ''
+        }'';
+        ExecStart = lib.mkForce ''
+          ${pkg}/bin/nginx-sso \
+            --config ${confPath} \
+            --frontend-dir ${pkg}/share/frontend
+        '';
+        Restart = "always";
+        User = "nginx-sso";
+        Group = "nginx-sso";
+      };
+    };
+
+    users.users.nginx-sso = {
+      isSystemUser = true;
+      group = "nginx-sso";
+    };
+
+    users.groups.nginx-sso = { };
+  };
+}