refactor(modules/impermanence): Move all optional dirs to their modules

This increases the locality of configurations and makes it easier to
see, what happens, when you enable a module.

7 files changed, 101 insertions, 79 deletions

diff --git a/flake/nixosConfigurations/common.nix b/flake/nixosConfigurations/common.nix
index bdf65a35..585e883b 100644
--- a/flake/nixosConfigurations/common.nix
+++ b/flake/nixosConfigurations/common.nix
@@ -12,7 +12,16 @@
     };
 
     home-manager.enable = true;
-    impermanence.enable = true;
+    impermanence = {
+      enable = true;
+
+      directories = [
+        "/etc/nixos"
+        "/var/log"
+        "/var/lib/systemd"
+        "/var/lib/nixos"
+      ];
+    };
     polkit.enable = true;
     power.enable = true;
 
diff --git a/modules/by-name/bl/bluetooth/module.nix b/modules/by-name/bl/bluetooth/module.nix
index bf1c6a90..486f6e6f 100644
--- a/modules/by-name/bl/bluetooth/module.nix
+++ b/modules/by-name/bl/bluetooth/module.nix
@@ -10,6 +10,10 @@ in {
   };
 
   config = lib.mkIf cfg.enable {
+    soispha.impermanence.directories = [
+      "/var/lib/bluetooth"
+    ];
+
     hardware = {
       bluetooth = {
         enable = true;
diff --git a/modules/by-name/bo/boot/module.nix b/modules/by-name/bo/boot/module.nix
index 711e9d23..8b71ce65 100644
--- a/modules/by-name/bo/boot/module.nix
+++ b/modules/by-name/bo/boot/module.nix
@@ -67,6 +67,12 @@ in {
       #   copyExtraFilesForBoot = copyExtraFiles;
       # };
 
+      # This should only be necessary for `lanzaboote`, but that is the current default in
+      # this module.
+      soispha.impermanence.directories = [
+        "/etc/secureboot"
+      ];
+
       boot = {
         initrd = {
           kernelModules = ["nvme" "btrfs"];
diff --git a/modules/by-name/im/impermanence/module.nix b/modules/by-name/im/impermanence/module.nix
index 9730dde6..513a91b7 100644
--- a/modules/by-name/im/impermanence/module.nix
+++ b/modules/by-name/im/impermanence/module.nix
@@ -10,32 +10,6 @@ in {
 
     directories = lib.mkOption {
       type = lib.types.listOf lib.types.str;
-      default =
-        [
-          "/etc/nixos"
-          "/var/log"
-          "/var/lib/systemd"
-          "/var/lib/nixos"
-        ]
-        ++ lib.optional config.networking.networkmanager.enable "/etc/NetworkManager"
-        ++ lib.optional config.boot.lanzaboote.enable "/etc/secureboot"
-        ++ lib.optional config.hardware.bluetooth.enable "/var/lib/bluetooth"
-        ++ lib.optional config.virtualisation.waydroid.enable "/var/lib/waydroid"
-        ++ lib.optional config.services.postgresql.enable "/var/lib/postgresql";
-
-      defaultText = lib.literalExpression ''
-        [
-          "/etc/nixos"
-          "/var/log"
-          "/var/lib/systemd"
-          "/var/lib/nixos"
-        ]
-        ++ lib.optional config.networking.networkmanager.enable "/etc/NetworkManager"
-        ++ lib.optional config.boot.lanzaboote.enable "/etc/secureboot"
-        ++ lib.optional config.hardware.bluetooth.enable "/var/lib/bluetooth"
-        ++ lib.optional config.virtualisation.waydroid.enable "/var/lib/waydroid"
-        ++ lib.optional config.services.postgresql.enable "/var/lib/postgresql"
-      '';
       description = "The directories to persist";
     };
   };
diff --git a/modules/by-name/ne/networking/module.nix b/modules/by-name/ne/networking/module.nix
index c5f0e491..8448e9b3 100644
--- a/modules/by-name/ne/networking/module.nix
+++ b/modules/by-name/ne/networking/module.nix
@@ -29,60 +29,71 @@ in {
     };
   };
 
-  config = {
-    networking.hostName = cfg.hostName;
-
-    systemd.network = lib.mkIf (cfg.mode == "systemd-networkd") {
-      networks = {
-        "tap0" = {
-          name = "tap0";
-          bridge = [
-            "virbr0"
-          ];
-        };
-        "enp4s0" = {
-          name = "enp4s0";
-          networkConfig = {
-            DHCP = "yes";
-            DNSOverTLS = "yes";
-            DNSSEC = "yes";
+  config =
+    lib.mkIf cfg.enable
+    (lib.modules.mkMerge [
+      {
+        networking.hostName = cfg.hostName;
+      }
+      (lib.mkIf (cfg.mode == "systemd-networkd") {
+        systemd.network = {
+          networks = {
+            "tap0" = {
+              name = "tap0";
+              bridge = [
+                "virbr0"
+              ];
+            };
+            "enp4s0" = {
+              name = "enp4s0";
+              networkConfig = {
+                DHCP = "yes";
+                DNSOverTLS = "yes";
+                DNSSEC = "yes";
+              };
+              bridge = [
+                "virbr0"
+              ];
+            };
           };
-          bridge = [
-            "virbr0"
-          ];
-        };
-      };
 
-      netdevs = {
-        "tap0" = {
-          netdevConfig = {
-            Name = "tap0";
-            Kind = "tap";
-          };
-          tapConfig = {
-            User = config.users.users."${cfg.userName}".uid;
-            Group = "libvirtd";
+          netdevs = {
+            "tap0" = {
+              netdevConfig = {
+                Name = "tap0";
+                Kind = "tap";
+              };
+              tapConfig = {
+                User = config.users.users."${cfg.userName}".uid;
+                Group = "libvirtd";
+              };
+            };
+            "virbr0" = {
+              netdevConfig = {
+                Name = "br0";
+                Kind = "bridge";
+              };
+            };
           };
         };
-        "virbr0" = {
-          netdevConfig = {
-            Name = "br0";
-            Kind = "bridge";
+      })
+
+      (lib.mkIf (cfg.mode == "NetworkManager") {
+        networking.networkmanager = {
+          enable = true;
+          dns = "default";
+          wifi = {
+            powersave = true;
           };
         };
-      };
-    };
 
-    networking.networkmanager = lib.mkIf (cfg.mode == "NetworkManager") {
-      enable = true;
-      dns = "default";
-      wifi = {
-        powersave = true;
-      };
-    };
+        soispha.impermanence.directories = [
+          "/etc/NetworkManager"
+        ];
 
-    users.users."${cfg.userName}".extraGroups = lib.mkIf (cfg.mode == "NetworkManager") [
-      "networkmanager" # allows to configure NetworkManager as this user
-    ];
-  };
+        users.users."${cfg.userName}".extraGroups = [
+          "networkmanager" # allows to configure NetworkManager as this user
+        ];
+      })
+    ]);
 }
diff --git a/modules/by-name/po/postgresql/module.nix b/modules/by-name/po/postgresql/module.nix
index c47a235c..62233e96 100644
--- a/modules/by-name/po/postgresql/module.nix
+++ b/modules/by-name/po/postgresql/module.nix
@@ -10,6 +10,10 @@ in {
   };
 
   config = lib.mkIf cfg.enable {
+    soispha.impermanence.directories = [
+      "/var/lib/postgresql"
+    ];
+
     services.postgresql = {
       enable = true;
     };
diff --git a/modules/by-name/wa/waydroid/module.nix b/modules/by-name/wa/waydroid/module.nix
index 4680db63..58bce7d1 100644
--- a/modules/by-name/wa/waydroid/module.nix
+++ b/modules/by-name/wa/waydroid/module.nix
@@ -1,5 +1,19 @@
-{...}: {
-  # FIXME: Running `waydroid session start` causes all fuse mounts instances to coredump <2023-09-02>
-  #        Thus this setting must be false.
-  virtualisation.waydroid.enable = false;
+{
+  config,
+  lib,
+  ...
+}: let
+  cfg = config.soispha.waydroid;
+in {
+  options.soispha.waydroid = {
+    enable = lib.mkEnableOption "waydroid";
+  };
+  config = lib.mkIf cfg.enable {
+    # FIXME: Running `waydroid session start` causes all fuse mounts instances to coredump <2023-09-02>
+    #        Thus this setting must be false.
+    virtualisation.waydroid.enable = false;
+    soispha.impermanence.directories = [
+      "/var/lib/waydroid"
+    ];
+  };
 }