Re: Is this quirky for a simple copy, editfiles operation?

[Mark Burgess]

On Thu, 2005-05-12 at 14:29 -0500, Brendan Strejcek wrote:
> Mark Burgess wrote:
> 
> > On Thu, 2005-05-12 at 14:06 -0500, Brendan Strejcek wrote:
> > > Roy MARANTZ wrote:
> > > 
> > > > If the action list is eliminated, IMHO, there needs to be some
> > > > mechanism to specify the ordering of actions. i.e. I need to
> > > > run shellcommands (and others) twice in order to make sure that
> > > > perconditions for certain actions are met. To be concrete, I need to
> > > > blow up a tar ball before I can override some file in it.
> > > 
> > > Wouldn't it be cool if you could just do:
> > > 
> > >     shellcommands:
> > >         did_some_command::
> > >             "/command/that/must/come/after some/command"
> > >         any::
> > >             "/some/command"
> > >                 define=did_some_command
> > > 
> > > and have cfagent figure out the rest? There is no complexity or
> > > ambiguity for the admin to sort out, and no imperative illusion.
> > 
> > 
> > You already can do this, if you observe AddInstallable.
> 
> But not for more complex dependency/ordering relationships, right?
> 
> It seems to me like there are cases where this breaks down, as I tried
> to outline in my previous long message.
> 
> In fact, here is a simple case where the current method breaks down,
> even with no cross-action dependencies.
> 
> Here is a one level case where it works:
> 
>     $ cat test_one_level
>     #!/usr/sbin/cfagent -qKf
>     
>     control:
>         AddInstallable = ( did_first )
>         actionsequence = ( shellcommands )
>     
>     shellcommands:
>         did_first::
>             "/bin/echo second"
>         any::
>             "/bin/echo first"
>                 define=did_first
> 
>     $ ./test_one_level
>     cfengine::/bin/echo first: first
>     cfengine::/bin/echo secon: second
> 
> But it breaks with two levels:
> 
>     $ cat test_two_level
>     #!/usr/sbin/cfagent -qKf
>     
>     control:
>         AddInstallable = ( did_first did_second )
>         actionsequence = ( shellcommands )
>     
>     shellcommands:
>         did_second::
>             "/bin/echo third"
>         did_first::
>             "/bin/echo second"
>                 define=did_second
>         any::
>             "/bin/echo first"
>                 define=did_first
> 
>     $ ./test_two_level
>     cfengine::/bin/echo first: first
>     cfengine::/bin/echo secon: second
>     $


You're right, it will not handle long chain dependencies, but then you
should not make such things! :-) In version 3 I hope that all of this
will be handled more elegantly. Now, if only I could find that time...


Mark