On Sunday, July 16, 2017 at 6:04:04 AM UTC-7, bert hajee wrote:
>
> Trevor, Reid,
>
> Thanks for taking the time to look at this.
>
> Exists should be checking the @property_hash object which is populated by
>> the instances method.
>> Something like:
>> def exists?
>> @property_hash[:ensure] == :present
>> end
>
>
>
> The real type does implement the exists? method by looking at the property
> hash. But when using the transition type, the property hash is not yet
> filled correctly, because the instances and prefetched methods are not
> (yet) called.
>
>
> On Friday, 14 July 2017 22:57:54 UTC+2, Reid Vandewiele wrote:
>>
>> I haven't dived into the code recently but depending on when prefetching
>> happens, it might be possible the Transition type is causing an "early"
>> invocation of #exists?. This is because Transition invokes a check of the
>> resource it is "prior to", thusly:
>> https://github.com/puppetlabs/puppetlabs-transition/blob/0.1.1/lib/puppet/provider/transition/ruby.rb#L68
>>
>> If it's the case that prefetch isn't called until the first instance of a
>> given type is evaluated, that might be something that's happening *after*
>> the Transition resource does its thing. Which could help explain why your
>> exists?() method, which uses prefetched data, isn't working.
>>
>>
> This seems to b what is happening.
>
> But what is the best way forward to solve this?
>
This could be seen as a problem with Transition, which would be best to see
fixed in the Transition module. The basic idea would be to make sure a
provider has done any prefetching it needs to before calling safe_insync?()
on a resource. That module is effectively opensource though so it depends
on someone being aware of the problem and having spare time to fix it.
Since that may not happen quickly, a workaround might be to ensure that at
least one instance of the type in question is evaluated prior to the
transition resource being evaluated. E.g.
file { 'prefetch':
path => '/dev/null',
ensure => present,
}
transition { 'transition a file resource':
require => File['prefetch'],
resource => File['/path/to/real/file'],
attributes => { ensure => absent },
prior_to => Service['example'],
}
This is just a mock example. The only thing it's really showing is that a
file "resource" called prefetch exists, doesn't really do anything, but is
guaranteed to be evaluated before a transition involving a different, real
file.
--
You received this message because you are subscribed to the Google Groups
"Puppet Developers" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
To view this discussion on the web visit
https://groups.google.com/d/msgid/puppet-dev/4e6e2c67-dd82-4f6b-9d34-e5e8775df04a%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
