change to writeShellApplication (#1)

use writeShellApplication to enable the automatic setting of PATH for dependencies.

Reviewed-on: #1

docker.nix

@@ -1,6 +1,20 @@
 { config, pkgs, ...}:
 
-pkgs.dockerTools.streamLayeredImage {
-      name = "node-red";
-      config.Cmd = [ "${pkgs.nodePackages.node-red}/bin/node-red" ];
+let
+name = "node-red";
+entrypoint = pkgs.writeShellApplication {
+  inherit name;
+
+  runtimeInputs = with pkgs; with nodePackages; [
+    node-red
+    ungoogled-chromium
+  ];
+
+  text = ''
+    node-red
+  '';
+};
+in pkgs.dockerTools.streamLayeredImage {
+      inherit name;
+      config.Cmd = [ "${entrypoint}/bin/entrypoint" ];
 }

flake.nix

@@ -11,10 +11,6 @@
     lib = nixpkgs.lib;
     pkgs = nixpkgs.legacyPackages.${system};
     streamImage = pkgs.callPackage (import ./docker.nix) {};
-    #pkgs.dockerTools.streamLayeredImage {
-    #  name = "node-red";
-    #  config.Cmd = [ "${pkgs.nodePackages.node-red}/bin/node-red" ];
-    #};
     in
   {