dockerTools.pullImage: control OS and architecture

This commit is contained in:
Nick Novitski 2018-06-12 17:56:13 -07:00
parent 64c6ff3dfc
commit c58b11d229
2 changed files with 26 additions and 5 deletions

View File

@ -649,6 +649,8 @@ merge:"diff3"
imageDigest = "sha256:20d9485b25ecfd89204e843a962c1bd70e9cc6858d65d7f5fadc340246e2116b"; <co xml:id='ex-dockerTools-pullImage-2' />
finalImageTag = "1.11"; <co xml:id='ex-dockerTools-pullImage-3' />
sha256 = "0mqjy3zq2v6rrhizgb9nvhczl87lcfphq9601wcprdika2jz7qh8"; <co xml:id='ex-dockerTools-pullImage-4' />
os = "linux"; <co xml:id='ex-dockerTools-pullImage-5' />
arch = "x86_64"; <co xml:id='ex-dockerTools-pullImage-6' />
}
</programlisting>
</example>
@ -664,9 +666,15 @@ merge:"diff3"
<callout arearefs='ex-dockerTools-pullImage-2'>
<para>
<varname>imageDigest</varname> specifies the digest of the image to be
downloaded. Skopeo can be used to get the digest of an image
downloaded. Skopeo can be used to get the digest of an image, with its
<varname>inspect</varname> subcommand. Since a given <varname>imageName</varname>
may transparently refer to a manifest list of images which support
multiple architectures and/or operating systems, supply the `--override-os`
and `--override-arch` arguments to specify exactly which image you
want. By default it will match the OS and architecture of the host the
command is run on.
<programlisting>
$ skopeo inspect docker://docker.io/nixos/nix:1.11 | jq -r '.Digest'
$ nix-shell --packages skopeo jq --command "skopeo --override-os linux --override-arch x86_64 inspect docker://docker.io/nixos/nix:1.11 | jq -r '.Digest'"
sha256:20d9485b25ecfd89204e843a962c1bd70e9cc6858d65d7f5fadc340246e2116b
</programlisting>
This argument is required.
@ -686,6 +694,18 @@ merge:"diff3"
This argument is required.
</para>
</callout>
<callout arearefs='ex-dockerTools-pullImage-5'>
<para>
<varname>os</varname>, if specified, is the operating system of the fetched image.
By default it's <literal>linux</literal>.
</para>
</callout>
<callout arearefs='ex-dockerTools-pullImage-6'>
<para>
<varname>arch</varname>, if specified, is the cpu architecture of the fetched image.
By default it's <literal>x86_64</literal>.
</para>
</callout>
</calloutlist>
</section>

View File

@ -36,10 +36,11 @@ rec {
in
{ imageName
# To find the digest of an image, you can use skopeo:
# skopeo inspect docker://docker.io/nixos/nix:1.11 | jq -r '.Digest'
# sha256:20d9485b25ecfd89204e843a962c1bd70e9cc6858d65d7f5fadc340246e2116b
# see doc/functions.xml
, imageDigest
, sha256
, os ? "linux"
, arch ? "x86_64"
# This used to set a tag to the pulled image
, finalImageTag ? "latest"
, name ? fixName "docker-image-${imageName}-${finalImageTag}.tar"
@ -59,7 +60,7 @@ rec {
sourceURL = "docker://${imageName}@${imageDigest}";
destNameTag = "${imageName}:${finalImageTag}";
} ''
skopeo copy "$sourceURL" "docker-archive://$out:$destNameTag"
skopeo --override-os ${os} --override-arch ${arch} copy "$sourceURL" "docker-archive://$out:$destNameTag"
'';
# We need to sum layer.tar, not a directory, hence tarsum instead of nix-hash.