Implement raspberry pi check using nixos-facter

machines/default.nix

@@ -25,11 +25,6 @@ flake-utils.lib.eachDefaultSystem (system: let
         '';
       };
 
-      isRaspberryPi = lib.mkOption {
-        default = false;
-        type = lib.types.bool;
-      };
-
       nixosModule = lib.mkOption {
         default = {...}: {};
         type = lib.types.anything;

machines/warwick/default.nix

@@ -1,10 +1,13 @@
 {
   machines.warwick = {
     arch = "aarch64-linux";
-    isRaspberryPi = true;
     facterReportPath = ./facter.json;
 
-    nixosModule.lab = {
+    nixosModule = {inputs, ...}: {
+      imports = [inputs.nixos-hardware.nixosModules.raspberry-pi-4];
+
+      config = {
+        lab = {
           storage.profile = "pi";
           monitoring.server.enable = true;
 
@@ -14,4 +17,6 @@
           };
         };
       };
+    };
+  };
 }

modules/default.nix

@@ -1,14 +1,13 @@
 {
   self,
   pkgs,
-  config,
   lib,
   inputs,
   machine,
+  config,
   ...
 }: {
-  imports =
+  imports = [
-    [
     ./storage.nix
     ./backups.nix
     ./networking
@@ -16,13 +15,12 @@
     ./monitoring
     ./k3s
     ./tailscale.nix
+    ./facter.nix
     machine.nixosModule
     inputs.disko.nixosModules.disko
     inputs.sops-nix.nixosModules.sops
     inputs.nix-snapshotter.nixosModules.nix-snapshotter
-      inputs.nixos-facter-modules.nixosModules.facter
+  ];
-    ]
-    ++ lib.lists.optional (machine.isRaspberryPi) inputs.nixos-hardware.nixosModules.raspberry-pi-4;
 
   config = {
     time.timeZone = "Europe/Amsterdam";
@@ -107,7 +105,7 @@
       fastfetch
     ];
 
-    boot = lib.mkIf (! machine.isRaspberryPi) {
+    boot = lib.mkIf (! config.facter.lab.isRaspberryPi) {
       loader = {
         systemd-boot.enable = lib.mkDefault true;
         efi.canTouchEfiVariables = true;

modules/facter.nix

@@ -0,0 +1,15 @@
+{
+  inputs,
+  lib,
+  config,
+  ...
+}: {
+  imports = [inputs.nixos-facter-modules.nixosModules.facter];
+
+  options.facter.lab = {
+    isRaspberryPi = lib.mkOption {
+      type = lib.types.bool;
+      default = config.facter.report.system == "aarch64-linux";
+    };
+  };
+}

modules/networking/default.nix

@@ -1,5 +1,6 @@
 {
   lib,
+  config,
   machine,
   ...
 }: {
@@ -16,7 +17,7 @@
       enable = true;
 
       networks = lib.attrsets.mergeAttrsList [
-        (lib.optionalAttrs (! machine.isRaspberryPi) {
+        (lib.optionalAttrs (! config.facter.lab.isRaspberryPi) {
           "30-main-nic" = {
             matchConfig.Name = "en*";
 
@@ -25,7 +26,7 @@
             };
           };
         })
-        (lib.optionalAttrs machine.isRaspberryPi {
+        (lib.optionalAttrs config.facter.lab.isRaspberryPi {
           "30-main-nic" = {
             matchConfig.Name = "end*";
             networkConfig = {