setup remote scanning

hosts/common/optional/print-server.nix

@@ -1,10 +1,18 @@
-{pkgs, ...}: {
+{pkgs, configVars, ...}: let
+  gatewayIp = configVars.networking.addresses.gateway.ip;
+in {
   networking.firewall = {
     allowedTCPPorts = [631];
     allowedUDPPorts = [631];
   };
 
   services = {
+    udev.packages = [pkgs.sane-airscan];
+    ipp-usb.enable = true;
+    saned = {
+      enable = true;
+      extraConfig = "${gatewayIp}/24";
+    };
     printing = {
       enable = true;
       drivers = [pkgs.hplip];
@@ -28,7 +36,13 @@
     };
   };
 
-  hardware.printers = {
+  hardware = {
+    sane = {
+      enable = true;
+      extraBackends = [pkgs.sane-airscan pkgs.hplipWithPlugin];
+      openFirewall = true;
+    };
+    printers = {
       ensurePrinters = [
         {
           name = "HP_Envy_6000";
@@ -43,4 +57,5 @@
       ];
       ensureDefaultPrinter = "HP_Envy_6000";
     };
+  };
 }

hosts/common/optional/printing.nix

@@ -7,6 +7,7 @@
 in {
   services = {
     udev.packages = [pkgs.sane-airscan];
+    hardware.sane.netConf = serverIp;
     printing = {
       enable = true;
       drivers = [pkgs.gutenprint pkgs.hplip];