I desire the ability to access DSL class parameters from within a provider. Similar to the pattern that is frequently seen with DSL defined types and a controlling class within a module. AFAIK, the alternatives for sharing data are ugly. Including: forcing the user to declare facts via ENC or an external fact source, using a file resource for "local IPC" (or sysv shm...), or adding parameters to the type and using a DSL defined type as wrapper. The later is the least objectionable but feels like it should be unnecessary; the data is already in the catalog.

Accessing the catalog from within a provider instance isn't very difficult since the instantiated resource has an accessor for it. Eg. `resource.catalog` Where I've hit a roadblock is trying to access the catalog from a class method. I've spent several hours poking at classes looking for an instance I could pry into or a singleton I could access without much luck. There was a suggestion on #puppet that it might be possible to obtain it via the indirector. I don't understand the indirection facility but I don't believe it has knowledge beyond the name of the catalog class. Eg. `Puppet::Indirector::Indirection.instance(:catalog).instance_variable_get(:@indirected_class).class` Perhaps I'm in error? I also failed to identify a reference back to the current transaction.

My last resort was to try passing the catalog from the resource to the provider as class data. This is problematic in that I can't identify a place to "hook" in that runs after both `Puppet::Util::ClassGen.genclass` and the providers are associated with a type but before the provider's class instances method is called. I've been resisting the temptation to stuff something into the `Puppet::Type.provide` method's option hash and monkey patching my way to victory...

I did have some limited success in that I was able to get into the catalog from `::prefetch` by adding class accessors for `catalog` to the provider and dropping this snippet into an autorequire block.

  if provider.class.respond_to?(:catalog)
    provider.class.catalog = catalog
  end

Of course, where I want access to the catalog data is from `::instances`. Have I missed something obvious?

Cheers,

-Josh

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