Ensure webpack frontend assets can be built using our minimum supported node version
Our documentation says we support building from source using node >= 4.3.0
: https://docs.gitlab.com/ce/install/installation.html#4-node
However, we do not actually test anywhere whether our build process will work with that node version. Our CI build images run 8.x and our omnibus build images run 6.x (soon to be upgraded to 8.x). This disparity has caused some issues now that would have otherwise gone uncaught: gitlab-org/gitlab-ce#43675
I propose that we:
- reassess our documented minimum node version (update v4 to v6 perhaps? v4 is no longer supported by some of our build tools)
- create a custom build image just for the
gitlab:assets:compile
job with our lowest-supported node version so that our pipelines will fail if the assets cannot be compiled in that version
/cc @stanhu