Excerpts from Ben Nemec's message of 2014-04-14 09:26:17 -0700: > tldr: I propose we use bash explicitly for all diskimage-builder scripts > (at least for the short-term - see details below). > > This is something that was raised on my linting changes to enable set -o > pipefail. That is a bash-ism, so it could break in the > diskimage-builder scripts that are run using /bin/sh. Two possible > fixes for that: switch to /bin/bash, or don't use -o pipefail >
What about this: if ! [ "$SHEBANG" = "#!/bin/bash" ] ; then report_warning Non bash shebang, skipping script lint fi > But I think this raises a bigger question - does diskimage-builder > require bash? If so, I think we should just add a rule to enforce that > /bin/bash is the shell used for everything. I know we have a bunch of > bash-isms in the code already, so at least in the short-term I think > this is probably the way to go, so we can get the benefits of things > like -o pipefail and lose the ambiguity we have right now. For > reference, a quick grep of the diskimage-builder source shows we have > 150 scripts using bash explicitly and only 24 that are plain sh, so > making the code truly shell-agnostic is likely to be a significant > amount of work. Yes, diskimage-builder is bash, not posix shell. We're not masochists. ;) > > In the long run it might be nice to have cross-shell compatibility, but > if we're going to do that I think we need a couple of things: 1) Someone > to do the work (I don't have a particular need to run dib in not-bash, > so I'm not signing up for that :-) 2) Testing in other shells - > obviously just changing /bin/bash to /bin/sh doesn't mean we actually > support anything but bash. We really need to be gating on other shells > if we're going to make a significant effort to support them. It's not > good to ask reviewers to try to catch every bash-ism proposed in a > change. This also relates to some of the unit testing work that is > going on right now too - if we had better unit test coverage of the > scripts we would be able to do this more easily. > I suggest that diskimage-builder's included elements should be /bin/bash only. When we have an element linting tool, non bash shebangs should be warnings we should enforce "no warnings". For t-i-e, we can strive for no warnings, but that would be a stretch goal and may involve refining the warnings. _______________________________________________ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
