initial set up for k3s service

clanServices/k3s/agent.nix

@@ -0,0 +1,28 @@
+{ config, lib, pkgs, ... }: 
+let
+  controller = head (lib.attrNames roles.controller.machines or {});
+in
+{
+  config = {
+    networking.firewall = {
+      allowedTCPPorts = [
+        6443 # k3s: required so that pods can reach the API server (running on port 6443 by default)
+        2379 # k3s, etcd clients: required if using a "High Availability Embedded etcd" configuration
+        2380 # k3s, etcd peers: required if using a "High Availability Embedded etcd" configuration
+      ];
+
+      allowedUDPPorts = [
+        8472 # k3s, flannel: required if using multi-node for inter-node networking
+      ];
+    };
+
+    services = {
+      k3s = {
+        enable = true;
+        role = "agent";
+        token = "somehow get the token that is generated for the controller"; # config.clan.core.vars.generators.k3s-token.token.value;
+        serverAddr = "https://<the ip address of the controller>";
+      };
+    };
+  };
+}