dockerTools: configurable compression schema

This commit adds support for swapping out the compression algorithm
used in all major docker-tools commands that generate images. The
default algorithm remains unchanged (gzip).

1 files changed, 22 insertions, 0 deletions

diff --git a/pkgs/build-support/docker/examples.nix b/pkgs/build-support/docker/examples.nix
index 5784e650dc2e..64dd112a950f 100644
--- a/pkgs/build-support/docker/examples.nix
+++ b/pkgs/build-support/docker/examples.nix
@@ -480,6 +480,22 @@ rec {
     layerC = layerOnTopOf layerB "c";
   in layerC;
 
+  bashUncompressed = pkgs.dockerTools.buildImage {
+    name = "bash-uncompressed";
+    tag = "latest";
+    compressor = "none";
+    # Not recommended. Use `buildEnv` between copy and packages to avoid file duplication.
+    copyToRoot = pkgs.bashInteractive;
+  };
+
+  bashZstdCompressed = pkgs.dockerTools.buildImage {
+    name = "bash-zstd";
+    tag = "latest";
+    compressor = "zstd";
+    # Not recommended. Use `buildEnv` between copy and packages to avoid file duplication.
+    copyToRoot = pkgs.bashInteractive;
+  };
+
   # buildImage without explicit tag
   bashNoTag = pkgs.dockerTools.buildImage {
     name = "bash-no-tag";
@@ -614,6 +630,12 @@ rec {
     layeredImageWithFakeRootCommands
   ];
 
+  mergeVaryingCompressor = pkgs.dockerTools.mergeImages [
+    redis
+    bashUncompressed
+    bashZstdCompressed
+  ];
+
   helloOnRoot = pkgs.dockerTools.streamLayeredImage {
     name = "hello";
     tag = "latest";