From 79f65ad002e47155ca2ba51dbdcda26663590643 Mon Sep 17 00:00:00 2001
From: Alex Eagle <alex@aspect.dev>
Date: Wed, 4 Oct 2023 13:07:24 -0700
Subject: [PATCH] refactor: extract function for mtree lines

---
 oci/private/tarball.sh.tpl | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/oci/private/tarball.sh.tpl b/oci/private/tarball.sh.tpl
index 0fdc8cc8..74136621 100644
--- a/oci/private/tarball.sh.tpl
+++ b/oci/private/tarball.sh.tpl
@@ -12,17 +12,23 @@ readonly TAGS_FILE="{{tags}}"
 # https://man.freebsd.org/cgi/man.cgi?mtree(8)
 # so that tar produces a deterministic output.
 mtree=$(mktemp)
+function add_to_tar() {
+    tar_path=$1
+    content=$2
+    readonly mtree_flags="uid=0 gid=0 mode=0755 time=1672560000 type=file"
+    echo >>"${mtree}" "blobs/${LAYER}.tar.gz ${mtree_flags} content=${IMAGE_DIR}/blobs/${LAYER}"
+}
 
 MANIFEST_DIGEST=$(${YQ} eval '.manifests[0].digest | sub(":"; "/")' "${IMAGE_DIR}/index.json" | tr  -d '"')
 MANIFEST_BLOB_PATH="${IMAGE_DIR}/blobs/${MANIFEST_DIGEST}"
 
 CONFIG_DIGEST=$(${YQ} eval '.config.digest  | sub(":"; "/")' ${MANIFEST_BLOB_PATH})
 CONFIG_BLOB_PATH="${IMAGE_DIR}/blobs/${CONFIG_DIGEST}"
-echo >>"${mtree}" "blobs/${CONFIG_DIGEST} uid=0 gid=0 mode=0755 time=1672560000 type=file content=${CONFIG_BLOB_PATH}"
+add_to_tar "blobs/${CONFIG_DIGEST}" "${CONFIG_BLOB_PATH}"
 
 LAYERS=$(${YQ} eval '.layers | map(.digest | sub(":"; "/"))' ${MANIFEST_BLOB_PATH})
 for LAYER in $(${YQ} ".[]" <<< $LAYERS); do 
-    echo >>"${mtree}" "blobs/${LAYER}.tar.gz  uid=0 gid=0 mode=0755 time=0 type=file content=${IMAGE_DIR}/blobs/${LAYER}"
+    add_to_tar "blobs/${LAYER}.tar.gz" "${IMAGE_DIR}/blobs/${LAYER}"
 done
 
 # Replace newlines (unix or windows line endings) with % character.
@@ -36,7 +42,7 @@ layers="${LAYERS}" \
         --null-input '.[0] = {"Config": env(config), "RepoTags": "${repo_tags}" | envsubst | split("%") | map(select(. != "")) , "Layers": env(layers) | map( "blobs/" + . + ".tar.gz") }' \
         --output-format json > "${STAGING_DIR}/manifest.json"
 
-echo >>"${mtree}" "manifest.json uid=0 gid=0 mode=0644 time=1672560000 type=file content=${STAGING_DIR}/manifest.json"
+add_to_tar "manifest.json" "${STAGING_DIR}/manifest.json"
 
 # We've created the manifest, now hand it off to tar to create our final output
 "${TAR}" --create --file "${TARBALL_PATH}" "@${mtree}"