tree 2c18ab71c252261ba700254ae5c5d622009effc1
parent b16f3e202f7cfd3fc7ed21248f21323b69399288
author Patrick Williams <patrick@stwcx.xyz> 1612635845 -0600
committer Patrick Williams <patrick@stwcx.xyz> 1613051694 -0600

build-unit-test-docker: invalidate base image weekly

Docker will cache an image built with the exact same commands,
so we only get latest Ubuntu packages rarely.  Add a date-based
echo command into the early stages of the base image build so
that we regularly get updates to all the packages in the base
image.

This invalidation, via echo, is only performed when running under
a Jenkins-like context.  The purpose of this distinction is so that
we are more likely to cache failures induced by an underlying OS
update in CI, but when developers run this script locally they rarely
see an invalidation that is not due to a code package update.

Add an environment variable option "FORCE_DOCKER_BUILD" which can be
set by developers to bypass the Docker cache and force all images
to be rebuilt, just in case they really want to do that sort of thing.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Iec92ebada513975d0806099083384dfca623f144