From aae8588182913549435332d0ac120e18d7afdab5 Mon Sep 17 00:00:00 2001
From: Louis Blin <45168934+lbpdt@users.noreply.github.com>
Date: Mon, 8 Mar 2021 20:36:13 +0000
Subject: dockerTools.buildLayeredImage: support fromImage

It is now possible to pass a `fromImage` to `buildLayeredImage` and
`streamLayeredImage`, similar to what `buildImage` currently supports.

This will prepend the layers of the given base image to the resulting
image, while ensuring that at most `maxLayers` are used. It will also
ensure that environment variables from the base image are propagated
to the final image.
---
 doc/builders/images/dockertools.section.md | 6 ++++++
 1 file changed, 6 insertions(+)

(limited to 'doc')

diff --git a/doc/builders/images/dockertools.section.md b/doc/builders/images/dockertools.section.md
index 40d4dba1b85..23662f9bbfe 100644
--- a/doc/builders/images/dockertools.section.md
+++ b/doc/builders/images/dockertools.section.md
@@ -111,6 +111,12 @@ Create a Docker image with many of the store paths being on their own layer to i
 
     *Default:* the output path's hash
 
+`fromImage` _optional_
+
+: The repository tarball containing the base image. It must be a valid Docker image, such as one exported by `docker save`.
+
+    *Default:* `null`, which can be seen as equivalent to `FROM scratch` of a `Dockerfile`.
+
 `contents` _optional_
 
 : Top level paths in the container. Either a single derivation, or a list of derivations.
-- 
cgit 1.4.1