1 files changed, 28 insertions, 0 deletions
diff --git a/nixpkgs/pkgs/build-support/fetchdocker/fetchdocker-builder.sh b/nixpkgs/pkgs/build-support/fetchdocker/fetchdocker-builder.sh
new file mode 100644
index 000000000000..489914a2a8b4
--- /dev/null
+++ b/nixpkgs/pkgs/build-support/fetchdocker/fetchdocker-builder.sh
@@ -0,0 +1,28 @@
+if [ -e "$NIX_ATTRS_SH_FILE" ]; then . "$NIX_ATTRS_SH_FILE"; elif [ -f .attrs.sh ]; then . .attrs.sh; fi
+source "${stdenv}/setup"
+echo "exporting ${repository}/${imageName} (tag: ${tag}) into ${out}"
+mkdir -p "${out}"
+
+cat <<EOF > "${out}/compositeImage.sh"
+#! ${bash}/bin/bash
+#
+# Create a tar archive of a docker image's layers, docker image config
+# json, manifest.json, and repositories json; this streams directly to
+# stdout and is intended to be used in concert with docker load, i.e:
+#
+# ${out}/compositeImage.sh | docker load
+
+# The first character follow the 's' command for sed becomes the
+# delimiter sed will use; this makes the transformation regex easy to
+# read. We feed tar a file listing the files we want in the archive,
+# because the paths are absolute and docker load wants them flattened in
+# the archive, we need to transform all of the paths going in by
+# stripping everything *including* the last solidus so that we end up
+# with the basename of the path.
+${gnutar}/bin/tar \
+  --transform='s=.*/==' \
+  --transform="s=.*-manifest.json=manifest.json=" \
+  --transform="s=.*-repositories=repositories=" \
+  -c "${manifest}" "${repositories}" -T "${imageFileStorePaths}"
+EOF
+chmod +x "${out}/compositeImage.sh"