Merge pull request #52870 from xtruder/pkgs/dockerTools/buildLayeredImage/extraCommands

dockerTools: allow to pass extraCommands, uid and gid to buildLayered image

pkgs/build-support/docker/default.nix

@@ -316,14 +316,21 @@ rec {
     # Files to add to the layer.
     contents,
     baseJson,
+    extraCommands,
     uid ? 0, gid ? 0,
   }:
     runCommand "${name}-customisation-layer" {
       buildInputs = [ jshon rsync tarsum ];
+      inherit extraCommands;
     }
     ''
       cp -r ${contents}/ ./layer
 
+      if [[ -n $extraCommands ]]; then
+        chmod ug+w layer
+        (cd layer; eval "$extraCommands")
+      fi
+
       # Tar up the layer and throw it into 'layer.tar'.
       echo "Packing layer..."
       mkdir $out
@@ -494,6 +501,8 @@ rec {
     # Time of creation of the image. Passing "now" will make the
     # created date be the time of building.
     created ? "1970-01-01T00:00:01Z",
+    # Optional bash script to run on the files prior to fixturizing the layer.
+    extraCommands ? "", uid ? 0, gid ? 0,
     # Docker's lowest maximum layer limit is 42-layers for an old
     # version of the AUFS graph driver. We pick 24 to ensure there is
     # plenty of room for extension. I believe the actual maximum is
@@ -501,8 +510,6 @@ rec {
     maxLayers ? 24
   }:
     let
-      uid = 0;
-      gid = 0;
       baseName = baseNameOf name;
       contentsEnv = symlinkJoin { name = "bulk-layers"; paths = (if builtins.isList contents then contents else [ contents ]); };
 
@@ -531,7 +538,7 @@ rec {
           name = baseName;
           contents = contentsEnv;
           baseJson = configJson;
-          inherit uid gid;
+          inherit uid gid extraCommands;
         };
       result = runCommand "docker-image-${baseName}.tar.gz" {
         buildInputs = [ jshon pigz coreutils findutils jq ];