Combine OVA generation steps

Previously this was done in three derivations (one to build the raw
disk image, one to convert to OVA, one to add a hydra-build-products
file). Now it's done in one step to reduce the amount of copying
to/from S3. In particular, not uploading the raw disk image prevents
us from hitting hydra-queue-runner's size limit of 2 GiB.

nixos/lib/make-disk-image.nix

@@ -22,12 +22,13 @@
 , # Shell code executed after the VM has finished.
   postVM ? ""
 
+, name ? "nixos-disk-image"
 }:
 
 with lib;
 
 pkgs.vmTools.runInLinuxVM (
-  pkgs.runCommand "nixos-disk-image"
+  pkgs.runCommand name
     { preVM =
         ''
           mkdir $out

nixos/modules/virtualisation/virtualbox-image.nix

@@ -22,7 +22,9 @@ in {
 
   config = {
 
-    system.build.virtualBoxImage = import ../../lib/make-disk-image.nix {
+    system.build.virtualBoxOVA = import ../../lib/make-disk-image.nix {
+      name = "nixos-ova-${config.system.nixosLabel}-${pkgs.stdenv.system}";
+
       inherit pkgs lib config;
       partitioned = true;
       diskSize = cfg.baseImageSize;
@@ -37,19 +39,13 @@ in {
       postVM =
         ''
           echo "creating VirtualBox disk image..."
-          ${pkgs.vmTools.qemu}/bin/qemu-img convert -f raw -O vdi $diskImage $out/disk.vdi
+          ${pkgs.vmTools.qemu}/bin/qemu-img convert -f raw -O vdi $diskImage disk.vdi
           rm $diskImage
-        '';
-    };
 
-    system.build.virtualBoxOVA = pkgs.runCommand "virtualbox-ova"
-      { buildInputs = [ pkgs.linuxPackages.virtualbox ];
-        vmName = "NixOS ${config.system.nixosLabel} (${pkgs.stdenv.system})";
-        fileName = "nixos-image-${config.system.nixosLabel}-${pkgs.stdenv.system}.ova";
-      }
-      ''
           echo "creating VirtualBox VM..."
           export HOME=$PWD
+          export PATH=${pkgs.linuxPackages.virtualbox}/bin:$PATH
+          vmName="NixOS ${config.system.nixosLabel} (${pkgs.stdenv.system})"
           VBoxManage createvm --name "$vmName" --register \
             --ostype ${if pkgs.stdenv.system == "x86_64-linux" then "Linux26_64" else "Linux26"}
           VBoxManage modifyvm "$vmName" \
@@ -61,12 +57,17 @@ in {
             --usb on --mouse usbtablet
           VBoxManage storagectl "$vmName" --name SATA --add sata --portcount 4 --bootable on --hostiocache on
           VBoxManage storageattach "$vmName" --storagectl SATA --port 0 --device 0 --type hdd \
-          --medium ${config.system.build.virtualBoxImage}/disk.vdi
+            --medium disk.vdi
 
           echo "exporting VirtualBox VM..."
           mkdir -p $out
-        VBoxManage export "$vmName" --output "$out/$fileName"
+          fn="$out/nixos-${config.system.nixosLabel}-${pkgs.stdenv.system}.ova"
+          VBoxManage export "$vmName" --output "$fn"
+
+          mkdir -p $out/nix-support
+          echo "file ova $fn" >> $out/nix-support/hydra-build-products
         '';
+    };
 
     fileSystems."/".device = "/dev/disk/by-label/nixos";
 

nixos/release.nix

@@ -150,31 +150,13 @@ in rec {
 
     with import nixpkgs { inherit system; };
 
-    let
+    hydraJob ((import lib/eval-config.nix {
-
-      config = (import lib/eval-config.nix {
       inherit system;
       modules =
         [ versionModule
           ./modules/installer/virtualbox-demo.nix
         ];
-      }).config;
+    }).config.system.build.virtualBoxOVA)
-
-    in
-      # Declare the OVA as a build product so that it shows up in Hydra.
-      hydraJob (runCommand "nixos-ova-${config.system.nixosVersion}-${system}"
-        { meta = {
-            description = "NixOS VirtualBox appliance (${system})";
-            maintainers = maintainers.eelco;
-          };
-          ova = config.system.build.virtualBoxOVA;
-          preferLocalBuild = true;
-        }
-        ''
-          mkdir -p $out/nix-support
-          fn=$(echo $ova/*.ova)
-          echo "file ova $fn" >> $out/nix-support/hydra-build-products
-        '') # */
 
   );