From 443305ab61655c93ed222ef23d7d0a342bffc6c9 Mon Sep 17 00:00:00 2001
From: Marco Vaschetto <vaschetto.marco@gmail.com>
Date: Wed, 10 Nov 2021 23:09:21 +0100
Subject: [PATCH] Allowing ubuntu element use local image

Patch allow to set path for local image source,
instead download latest or use the cached image.
This permit to build image also in environment without internet access.

re-propose of patch: https://review.opendev.org/c/openstack/diskimage-builder/+/809009

Change-Id: I54395b09af339caee040326b809e8fbf8b0e7d6a
---
 diskimage_builder/elements/ubuntu/README.rst  |  5 +++
 .../99-cloud-init-datasources.bash            |  1 +
 .../ubuntu/root.d/10-cache-ubuntu-tarball     | 40 +++++++++----------
 3 files changed, 26 insertions(+), 20 deletions(-)

diff --git a/diskimage_builder/elements/ubuntu/README.rst b/diskimage_builder/elements/ubuntu/README.rst
index ad8af102..cf2aa5b4 100644
--- a/diskimage_builder/elements/ubuntu/README.rst
+++ b/diskimage_builder/elements/ubuntu/README.rst
@@ -21,5 +21,10 @@ Overrides:
    ``(universe|multiverse)``
  * Setting ``DIB_DISTRIBUTION_MIRROR_UBUNTU_INSECURE`` updates apt
    settings to allow insecure/unuthenticated repositories.
+ * Setting ``DIB_OFFLINE`` will prevent to download again the source image
+   if is already present in to $DIB_IMAGE_CACHE path.
+ * Setting ``DIB_LOCAL_IMAGE`` to use a image from a local source (full path and file name) 
+   and not download image from internet. Local source for release Trusty
+   have to be tar.gz format. For other more recent release get the squashfs image.
 
 .. element_deps::
diff --git a/diskimage_builder/elements/ubuntu/environment.d/99-cloud-init-datasources.bash b/diskimage_builder/elements/ubuntu/environment.d/99-cloud-init-datasources.bash
index bd25409f..dd073abc 100644
--- a/diskimage_builder/elements/ubuntu/environment.d/99-cloud-init-datasources.bash
+++ b/diskimage_builder/elements/ubuntu/environment.d/99-cloud-init-datasources.bash
@@ -2,3 +2,4 @@
 # allowing the Ec2 data source from being queried on first boot, unless
 # specified otherwise.
 export DIB_CLOUD_INIT_DATASOURCES=${DIB_CLOUD_INIT_DATASOURCES:-"Ec2"}
+export DIB_LOCAL_IMAGE=${DIB_LOCAL_IMAGE:-""}
diff --git a/diskimage_builder/elements/ubuntu/root.d/10-cache-ubuntu-tarball b/diskimage_builder/elements/ubuntu/root.d/10-cache-ubuntu-tarball
index 4f7ba3ea..740dc7bc 100755
--- a/diskimage_builder/elements/ubuntu/root.d/10-cache-ubuntu-tarball
+++ b/diskimage_builder/elements/ubuntu/root.d/10-cache-ubuntu-tarball
@@ -14,7 +14,7 @@ shopt -s extglob
 
 DIB_RELEASE=${DIB_RELEASE:-trusty}
 DIB_CLOUD_IMAGES=${DIB_CLOUD_IMAGES:-http://cloud-images.ubuntu.com/$DIB_RELEASE/current}
-if [ $DIB_RELEASE != "trusty" ] && [ $DIB_RELEASE != "xenial" ]; then
+if [ $DIB_RELEASE != "trusty" ] ; then
     BASE_IMAGE_FILE=${BASE_IMAGE_FILE:-$DIB_RELEASE-server-cloudimg-$ARCH.squashfs}
 else
     BASE_IMAGE_FILE=${BASE_IMAGE_FILE:-$DIB_RELEASE-server-cloudimg-$ARCH-root.tar.gz}
@@ -25,36 +25,36 @@ CACHED_FILE_LOCK=$DIB_LOCKFILES/$BASE_IMAGE_FILE.lock
 CACHED_SUMS=$DIB_IMAGE_CACHE/SHA256SUMS.ubuntu.$DIB_RELEASE.$ARCH
 
 function get_ubuntu_tarball() {
-    if [ -n "$DIB_OFFLINE" -a -f "$CACHED_FILE" ] ; then
-        echo "Not checking freshness of cached $CACHED_FILE."
+    if [ -n "$DIB_LOCAL_IMAGE" ] ; then
+        echo "Using local image without download"
+        if [ ! -f "$DIB_LOCAL_IMAGE" ] ; then
+            echo "Unable to find image $DIB_LOCAL_IMAGE locally! Check path and file name to source image"
+        exit 1
+        fi
+        IMAGE_PATH=$DIB_LOCAL_IMAGE
     else
-        echo "Fetching Base Image"
-        $TMP_HOOKS_PATH/bin/cache-url $SHA256SUMS $CACHED_SUMS
-        $TMP_HOOKS_PATH/bin/cache-url \
-            $DIB_CLOUD_IMAGES/$BASE_IMAGE_FILE $CACHED_FILE
-        pushd $DIB_IMAGE_CACHE
-        if ! grep "$BASE_IMAGE_FILE" $CACHED_SUMS | sha256sum --check - ; then
-            # It is likely that an upstream http(s) proxy has given us a skewed
-            # result - either a cached SHA file or a cached image. Use cache-busting
-            # to get (as long as caches are compliant...) fresh files.
-            # Try the sha256sum first, just in case that is the stale one (avoiding
-            # downloading the larger image), and then if the sums still fail retry
-            # the image.
-            $TMP_HOOKS_PATH/bin/cache-url -f $SHA256SUMS $CACHED_SUMS
+        if [ -n "$DIB_OFFLINE" -a -f "$CACHED_FILE" ] ; then
+            echo "Not checking freshness of cached $CACHED_FILE."
+        else
+            echo "Fetching Base Image"
+            $TMP_HOOKS_PATH/bin/cache-url $SHA256SUMS $CACHED_SUMS
+            $TMP_HOOKS_PATH/bin/cache-url \
+                $DIB_CLOUD_IMAGES/$BASE_IMAGE_FILE $CACHED_FILE
+            pushd $DIB_IMAGE_CACHE
             if ! grep "$BASE_IMAGE_FILE" $CACHED_SUMS | sha256sum --check - ; then
                 $TMP_HOOKS_PATH/bin/cache-url -f \
                     $DIB_CLOUD_IMAGES/$BASE_IMAGE_FILE $CACHED_FILE
                 grep "$BASE_IMAGE_FILE" $CACHED_SUMS | sha256sum --check -
             fi
         fi
-        popd
+        IMAGE_PATH=$DIB_IMAGE_CACHE/$BASE_IMAGE_FILE
     fi
     # Extract the base image (use --numeric-owner to avoid UID/GID mismatch between
     # image tarball and host OS e.g. when building Ubuntu image on an openSUSE host)
-    if [ $DIB_RELEASE != "trusty" ] && [ $DIB_RELEASE != "xenial" ]; then
-        sudo unsquashfs -f -d $TARGET_ROOT $DIB_IMAGE_CACHE/$BASE_IMAGE_FILE
+    if [ "$DIB_RELEASE" != "trusty" ] ; then
+            sudo unsquashfs -f -d $TARGET_ROOT $IMAGE_PATH
     else
-        sudo tar -C $TARGET_ROOT --numeric-owner -xzf $DIB_IMAGE_CACHE/$BASE_IMAGE_FILE
+            sudo tar -C $TARGET_ROOT --numeric-owner -xzf $IMAGE_PATH
     fi
 }