Re: [gentoo-alt] Allow non-interactive bootstrap to be stopped at arbitrary stages

[Fabian Groffen]

What I gather from this discussion is that the bootstrap script is
complex, and grew more complexity over the years.

Back in the early days, there was just documentation, one needed to
follow.  Since this frequently needed an update, and people kept using
older copies, at some point the bootstrap-prefix.sh script was
introduced.

This script followed the documentation to the letter.  It was an exact
replica of the instructions in the bootstrap document.  This included
the notions of 3 stages and a world recompile.

Today, the purpose of the stages have blurred, and seem more like
batches in which to do things.  Some of the initial intentions still
stand out, e.g. that stage1 is there to provide a working portage
environment with some minimal efforts.  Minimal got redefined as soon as
we had to install python and more and more tools seemed necesary (sed,
path, awk, etc.).

Now, it seems you need to cut time and sort of bootstrap up-to a stage.
Would it be an option to simply add a(nother) var that will control the
interactive target in terms of how far it will run along.  Normal resume
strategies it employs already would simply allow a next run to run along
further.

I think above can be done easily with a few lines of code.

Let me know what you think.

Thanks,
Fabian

On 23-01-2020 13:31:05 +1100, Sam Pfeiffer wrote:
> Grobian, any input about this?
>
> On Thu, Jan 16, 2020, 17:39 Sam Pfeiffer <[1]sammypfeiffer@×××××.com> wrote:
>
> > Hello Benda,
>
> > To be more specific... To easily go thru it I made a gist with the latest
> > version of bootstrap-prefix.sh and I'll be pointing to specific lines (this
> > also helps me recap why I did this, as I remember using stage{1,2,3} didn't
> > work for me when I first came into this):
>
> > When you execute bootstrap-prefix.sh without arguments (other than the
> > EPREFIX, ./bootstrap-prefix.sh /MY/EPREFIX) it calls this line:
>
> > [2]https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L3033
>
> > Calling bootstrap_interactive
>
> > If you give an extra argument (./bootstrap-prefix.sh /MY/EPREFIX
> > [noninteractive, stage{1,2,3}]) it calls this line:
> > [3]https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L3082
>
> > bootstrap_${TODO#non} || exit 1
>
> > Which, on the noninteractive case, goes to the same place than no arguments
> > (bootstrap_interactive). But in the stage{1,2,3} calls directly the
> > bootstrap_stageX function.
>
> > The thing is, noninteractive does some checks, finds resources and sets up
> > environment variables like:
>
> >   * Check for bad flags:
> >   [4]https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2200-L2247
> >   * We find a gcc:
> >   [5]https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2273-L2433
> >   * We get a cpu count and adjust -j for Make:
> >   [6]https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2443-L2501
> >   * Check if we deal with multilib systems:
> >   [7]https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2503-L2576
> >   * Check if we are boostrapping from a Gentoo system:
> >   [8]https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2578-L2608
> >   * Set our EPREFIX:
> > [9]https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2610-L2681
>
> > Which is summarised at the end by setting the environment variables EPREFIX,
> > CHOST, PATH, MAKEOPTS.
>
> > And then finally calls bootstrap_stage1_log, which runs bootstrap_stage1
> > itself.
>
> > [10]https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2724-L2726
>
> > Then, we compare with calling bootstrap-prefix.sh EPREFIX stage1...
>
> > Calls bootstrap_stage1():
> > [11]https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L1355
>
> > And as you can see it won't do any of the extra work done in
> > bootstrap_interactive().
>
> > I'm not that versed in this script, so I may be missing something easy to
> > overcome this (or I don't know enough about what is going on), but there is no
> > separate function that does everything in bootstrap_interactive without
> > calling bootstrap_stage1. And bootstrap_stage1 does not do all that setup that
> > bootstrap_interactive does. So that's how I came to my proposal.
>
> > If there is some patch to enable that setup from bootstrap_interactive with
> > bootstrap_stage1, that would be a good alternative, I guess. I still like the
> > fact that with my approach you are just saying "bootstrap everything until
> > this step" instead of needing to manually do bootstrap_setup (imaginary
> > function I just named) then bootstrap_stage1, then bootstrap_stage2, then
> > bootstrap_stage3, and then no argument for the last emerge -e system, to get
> > to a specific bootstrap stage, but that's just commodity.
>
> > Let me know if I'm wrong somewhere or you think of any better solution!
>
> > On Thu, 16 Jan 2020 at 13:42, Sam Pfeiffer <[12]sammypfeiffer@×××××.com>
> > wrote:
>
> >> Hi Benda,
>
> >> Thanks for your reply.
>
> >> On Thu, 16 Jan 2020 at 13:01, Benda Xu <[13]heroxbd@g.o> wrote:
>
> >>> Hi Sam,
>
> >>> Sam Pfeiffer <[14]sammypfeiffer@×××××.com> writes:
>
> >>> > To ease automated building and debugging of the bootstrap of Gentoo
> >>> > Prefix I would like to propose a patch to add the option to stop the
> >>> > non-interactive bootstrap on specific stages of the bootstrap.
> >>> >
> >>> > I'm currently doing this in my CI projects [1][2] and I'd love to have
> >>> > this added upstream.
> >>> >
> >>> > I propose a patch like this:
> >>> >[15]https://gist.github.com/awesomebytes/3468477c6c90fe3d985372d50aabba9f
> >>> >
> >>> > Which is what I'm currently using. It just adds another optional
> >>> >parameter to the commandline (a 3rd one) in non-interactive mode which
> >>> >you tell it after which stage to stop (stage1, stage2, stage3).
>
> >>> > I'm not the most versed person in bash, so maybe there is a more
> >>> > conceptually beautiful way of doing this. My patch is just a proposal
> >>> > (that has been tested and running).
> >>> >
> >>> > This patch is useful because it allows:
> >>> > 1) Easier debugging by stages.
>
> >>> > 2) Allows to split the bootstrap job in parts in CI environments with
> >>> > time limits on jobs to run (e.g. Azure Pipelines time limit is 6h*,
> >>> > and the bootstrap takes in between 5h40-6h40 depending on random
> >>> > things like time to download things, and load on the machine... or
> >>> > packages just taking longer to build).
> >>> >
> >>> > And this patch should not change anything to anyone else (AFAIK).
>
> >>> Are you aware that in bootstrap-prefix.sh you can specify the stage you
> >>> are after?  e.g.
>
> >>>    [16]https://wiki.gentoo.org/wiki/Project:Prefix/Manual_Bootstrap#Stage_1
>
> >>> The text above that could be outdated, but PATH exports and stage1~3 are
> >>> correct.
>
> >> I'm aware, but the behaviour (relating to environment variables and choosing
> >> CPU numbers) differs from the
>
> >> noninteractive argument. I'd like to keep the CI environment as close as a
> >> user executing ./bootstrap-prefix.sh EPREFIX as possible.
>
> >> That's why I'm proposing this addition. Another approach could be modifying
> >> the current argument to do the same than the noninteractive one.
>
> >> But that may break the workflow of someone, and I don't want that.
>
> >>  
>
> >>> > Thanks for your time and feedback!
> >>> >
> >>> > P.S.: I'm used to the GitHub/GitLab workflow of having a graphical
> >>> > interface to do a Pull Request... I don't know how to do this with
> >>> > [17]https://gitweb.gentoo.org/repo/proj/prefix.git/ If there is no way,
> >>> > aside of the goal of this email, I'd propose to have a mirror in
> >>> > GitHub.
>
> >>> Yes, that's a good to have for me, but not in high priority.
>
> >>> > *If you are curious, Stage 1 takes 8min~, Stage 2 takes 29min~, Stage
> >>> > 3 takes 2h30min~, emerge system takes 2h35min~ on Azure Pipelines,
> >>> > approximately.
>
> >>> Thank you so much for all your work!  That's extremely helpful to keep
> >>> the quality of Prefix codebase.
>
> >>> > [1] [18]https://github.com/awesomebytes/gentoo_prefix_ci
> >>> > [2] [19]https://github.com/awesomebytes/gentoo_prefix_ci_32b
>
> >>> Yours,
> >>> Benda
>
> >> --
>
> >> Sammy Pfeiffer
> >> PhD Candidate at The Magic Lab within UTS.
>
> > --
>
> > Sammy Pfeiffer
> > PhD Candidate at The Magic Lab within UTS.
>
>
>
>  References:
>    1. mailto:sammypfeiffer@×××××.com
>    2. https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L3033
>    3. https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L3082
>    4. https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2200-L2247
>    5. https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2273-L2433
>    6. https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2443-L2501
>    7. https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2503-L2576
>    8. https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2578-L2608
>    9. https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2610-L2681
>   10. https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L2724-L2726
>   11. https://gist.github.com/awesomebytes/ba4df9c6ef3ab5742cb9aceed7998c3d#file-bootstrap-prefix-sh-L1355
>   12. mailto:sammypfeiffer@×××××.com
>   13. mailto:heroxbd@g.o
>   14. mailto:sammypfeiffer@×××××.com
>   15. https://gist.github.com/awesomebytes/3468477c6c90fe3d985372d50aabba9f
>   16. https://wiki.gentoo.org/wiki/Project:Prefix/Manual_Bootstrap#Stage_1
>   17. https://gitweb.gentoo.org/repo/proj/prefix.git/
>   18. https://github.com/awesomebytes/gentoo_prefix_ci
>   19. https://github.com/awesomebytes/gentoo_prefix_ci_32b
>
> read_char: errno==EILSEQ; invalid byte sequence for UTF-8:
-- 
Fabian Groffen
Gentoo on a different level