treewide: rework CI, allow skipping some hosts

some of the hosts aren't actually deployed that often, while building
their configuration is long (eg. kernel rebuilds).

.ci.sh

@@ -14,10 +14,14 @@ set -x
 while read hostOutput; do
   echo "${hostOutput}"
   nixos-rebuild build --verbose --flake ".#${hostOutput}"
-done < <(nix eval -I nixpkgs=$(nix flake metadata nixpkgs --json | jq -r .path) --raw --impure --expr '
-    with import <nixpkgs> { };
-    (lib.strings.concatStringsSep "\n"
-    (lib.mapAttrsToList (n: v: n)
-      (lib.attrsets.filterAttrs (n: v: v.pkgs.system == pkgs.system)
-        (builtins.getFlake(builtins.toString ./.)).outputs.nixosConfigurations)))
-'; echo "")
+done < <(nix eval --raw --impure --expr '
+let
+  hosts = (import ./meta.nix).hosts;
+  filterHosts = hosts: (
+    builtins.filter (h: !hosts.${h}.ciSkip && hosts.${h}.system == builtins.currentSystem)
+      (builtins.attrNames hosts)
+  );
+in
+  builtins.concatStringsSep "\n" (filterHosts hosts)
+'; echo ""
+)

.github/workflows/ci.yml

@@ -20,9 +20,13 @@ jobs:
             echo -n "matrix="
             nix eval --raw --impure --expr '
                 let
-                    f = configs: builtins.groupBy (n: configs.${n}.pkgs.system) (builtins.attrNames configs);
+                    groupHosts = hosts:
+                        builtins.groupBy (n: hosts.${n}.system)
+                            (builtins.filter (h: !hosts.${h}.ciSkip)
+                                (builtins.attrNames hosts));
+                    hosts = (import ./meta.nix).hosts;
                 in
-                    builtins.toJSON (f (builtins.getFlake(builtins.toString ./.)).outputs.nixosConfigurations)'
+                    builtins.toJSON (groupHosts hosts)'
             echo ""
           }  >> "$GITHUB_OUTPUT"
 

meta.nix

@@ -10,6 +10,7 @@ in {
   hosts = builtins.mapAttrs (name: value:
     {
       targetHost = name + "." + defaultDomain;
+      ciSkip = false;
     }
     // builtins.fromJSON (builtins.readFile (./nixos/. + "/${name}/meta.json")))
     (builtins.readDir ./nixos);

nixos/akamanto/meta.json

@@ -1,4 +1,5 @@
 {
   "publicKey": "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIKb4i+BmIb2wiT4y5uWsCOmSo1dRp6Ql36toUsRHN6pC",
+  "ciSkip": true,
   "system": "aarch64-linux"
-}
+}

nixos/amanojaku/meta.json

@@ -1,4 +1,5 @@
 {
   "publicKey": "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIE4rFVYs5t4uBpZK9kmDQkr9ONLDE41jOCP/tMmM+SMb",
+  "ciSkip": true,
   "system": "x86_64-linux"
 }

nixos/kamaitachi/meta.json

@@ -1,4 +1,5 @@
 {
   "publicKey": "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIKb4i+BmIb2wiT4y5uWsCOmSo1dRp6Ql36toUsRHN6pC",
+  "ciSkip": true,
   "system": "aarch64-linux"
 }

nixos/khas/meta.json

@@ -1,4 +1,5 @@
 {
   "publicKey": "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIAs/jPJBvAVB+BgkywNDSUqcuqzFaWTmBn5hTnKm1wjF",
+  "ciSkip": true,
   "system": "x86_64-linux"
 }