From 8b83196024bd7d88f5f0b9d318a103e2de7dae9b Mon Sep 17 00:00:00 2001
From: Noam Angel <noama@mellanox.com>
Date: Sun, 10 Feb 2019 14:07:06 +0000
Subject: [PATCH] Add option to skip update packages

in same cases it is required to avoid update all existing packages,
doing so can result in release update which is currently not possible
unless you not include "base" element.

"base" element used for most distribution (rhel, debain), and is
necessary for most cloud operations, this patch add
"DIB_AVOID_PACKAGES_UPDATE" parameter to skip updating all packages.

usecases for this patch can be:
 * Avoid release update when building old release ex. RHEL7.5.
 * build on network-less environment.

usage:
DIB_AVOID_PACKAGES_UPDATE=1

or
DIB_AVOID_PACKAGES_UPDATE=0

Change-Id: I71192b23c8f0bc48b348fe7377bf8a2399b53792
---
 diskimage_builder/elements/base/README.rst                | 8 ++++++++
 .../elements/base/environment.d/10-base-defaults          | 1 +
 diskimage_builder/elements/base/install.d/00-up-to-date   | 4 +++-
 3 files changed, 12 insertions(+), 1 deletion(-)
 create mode 100644 diskimage_builder/elements/base/environment.d/10-base-defaults

diff --git a/diskimage_builder/elements/base/README.rst b/diskimage_builder/elements/base/README.rst
index 1984ea86..f105048f 100644
--- a/diskimage_builder/elements/base/README.rst
+++ b/diskimage_builder/elements/base/README.rst
@@ -20,6 +20,14 @@ customize cloud-init's management of `/etc/hosts`:
    preserve diskimage-builder's current default behavior in the
    future, set the variable to "localhost" explicitly.)
 
+The 'DIB_AVOID_PACKAGES_UPDATE' environment variable can be used to
+avoid updating all packages, useful when wanting to avoid release
+update.
+
+ * 'DIB_AVOID_PACKAGES_UPDATE' default is '0', all packages will be updated.
+
+ * set 'DIB_AVOID_PACKAGES_UPDATE' to '1' to avoid updating all packages.
+
 Notes:
 
  * If you are getting warnings during the build about your locale
diff --git a/diskimage_builder/elements/base/environment.d/10-base-defaults b/diskimage_builder/elements/base/environment.d/10-base-defaults
new file mode 100644
index 00000000..b555a262
--- /dev/null
+++ b/diskimage_builder/elements/base/environment.d/10-base-defaults
@@ -0,0 +1 @@
+export DIB_AVOID_PACKAGES_UPDATE=${DIB_AVOID_PACKAGES_UPDATE:-0}
\ No newline at end of file
diff --git a/diskimage_builder/elements/base/install.d/00-up-to-date b/diskimage_builder/elements/base/install.d/00-up-to-date
index d2b45d74..996ba275 100755
--- a/diskimage_builder/elements/base/install.d/00-up-to-date
+++ b/diskimage_builder/elements/base/install.d/00-up-to-date
@@ -8,4 +8,6 @@ fi
 set -eu
 set -o pipefail
 
-install-packages -u
+if [ ${DIB_AVOID_PACKAGES_UPDATE} -eq 0 ]; then
+    install-packages -u
+fi