Add new dynamicUser option to disable DynamicUser.

Default is true which leaves dynamicUser enabled, and when set to false
the systemd service DynamicUser option is disabled but all of the other
options which are automatically enabled by that option are set to
default enabled.

Author: thalin

modules/geth/default.nix

@@ -133,7 +133,7 @@ in {
                 (mkIf (cfg.args.authrpc.jwtsecret != null) {
                   LoadCredential = ["jwtsecret:${cfg.args.authrpc.jwtsecret}"];
                 })
-                (mkIf (cfg.user != null) {
+                (mkIf (!cfg.dynamicUser) {
                   DynamicUser = mkForce false;
                   RemoveIPC = mkDefault true;
                   PrivateTmp = mkDefault true;

modules/geth/options.nix

@@ -9,14 +9,20 @@
     options = rec {
       enable = mkEnableOption "Go Ethereum Node";
 
+      inherit args;
+
+      dynamicUser = mkOption {
+        type = types.bool;
+        default = true;
+        description = "Whether to use systemd's DynamicUser feature.";
+      };
+
       user = mkOption {
         type = types.nullOr types.str;
         default = null;
         description = "User to run the service as.";
       };
 
-      inherit args;
-
       extraArgs = mkOption {
         type = types.listOf types.str;
         description = "Additional arguments to pass to Go Ethereum.";