[chef] Re: New Custom Resources

[Lamont Granquist < >]

yeah, you want 1:1 mapping of resources and providers, and then wire 
them up with provides.  look at how the package resources use 
yum_package resource+provider, apt_package resource+provider and then 
wire themselves up to package on the DSL.  the Chef::Resource::Package 
resource is now an abstract base class that isn't wired up to 'package' 
any more (its just used for code sharing).  the objects that you can 
really make are Chef::Resource::YumPackage and 
Chef::Resource::AptPackage, and those always wrap 
Chef::Provider::Package::Yum and Chef::Provider::Package::Apt.

the multiple-provider abstraction is really kind of deprecated (but not 
really) because its a leaky abstraction.  once you wind up sprouting 
different validations that you want to do on the two different 
providers, then you want to wrap them with 1:1 specific resources that 
do the validation for the specific provider.  the way that Chef 11 
worked where you could get a vanilla Chef::Resource::Package that wraps 
a Chef::Provider::Package::Yum but you couldn't pass any of the 
yum-specific options through that was mostly confusing -- there's 
possibly a bit of utility there in being able to validate that the 
package options you were using were valid across all platforms, but i 
don't think anyone used it that way, and only the people who really 
deeply thought about the classes you were instantiating.

and if you look at the service resources with the multiple providers 
behind it, it is just a disaster.  don't ever go down the road of 
replicating those patterns.  that source code should come with a big 
warning that its an example of a chef antipattern.

On 10/09/2015 07:42 AM, Cassiano Leal wrote:
> Hi list,
>
> I’m having a look into the newly released Chef Client 12.5 and I really like 
> the new streamlined custom resources.
>
> I couldn’t find information on how to deal with multiple providers in this 
> new model though. What’s the thought around that? Create different custom 
> resources for what used to be different providers?
>
> Cheers!
> Cassiano Leal