allow extra apps in Nextcloud

modules/services/nextcloud-server.nix

@@ -134,6 +134,27 @@ in
       '';
     };
 
+    extraApps = lib.mkOption {
+      type = lib.types.raw;
+      description = ''
+        Extra apps to install. Should be a function returning an attrSet of appid to packages
+        generated by fetchNextcloudApp. The appid must be identical to the “id” value in the apps
+        appinfo/info.xml. You can still install apps through the appstore.
+      '';
+      default = apps: {};
+      example = lib.literalExpression ''
+        apps: {
+          inherit (apps) mail calendar contact;
+          phonetrack = pkgs.fetchNextcloudApp {
+            name = "phonetrack";
+            sha256 = "0qf366vbahyl27p9mshfma1as4nvql6w75zy2zk5xwwbp343vsbc";
+            url = "https://gitlab.com/eneiluj/phonetrack-oc/-/wikis/uploads/931aaaf8dca24bf31a7e169a83c17235/phonetrack-0.6.9.tar.gz";
+            version = "0.6.9";
+          };
+        }
+      '';
+    };
+
     debug = lib.mkOption {
       type = lib.types.bool;
       description = "Enable more verbose logging.";
@@ -209,6 +230,10 @@ in
       # Very important for a bunch of scripts to load correctly. Otherwise you get Content-Security-Policy errors. See https://docs.nextcloud.com/server/13/admin_manual/configuration_server/harden_server.html#enable-http-strict-transport-security
       https = config.shb.ssl.enable;
 
+      extraApps = cfg.extraApps pkgs.nextcloud27Packages.apps;
+      extraAppsEnable = true;
+      appstoreEnable = true;
+
       extraOptions = let
         protocol = if config.shb.ssl.enable then "https" else "http";
       in {