[chef] Re: Re: Passing values from resource to resource

[Noah Kantrowitz < >]

This is incorrect and is just a side effect of chef-shell being a bit odd. 
String interpolation is a Ruby feature and will happen at compile time as 
normal. If you want to delay runtime of something you need to wrap it in a 
ruby_block or LWRP. You can either use node attars to communicate between 
resources, or node.run_state which is a hash that is reset for each run.

--Noah

On Dec 13, 2012, at 4:38 PM, Peter Norton wrote:

> I asked a somewhat related question in IRC yesterday, so I'll take a stab 
> at answering you here.
> 
> You can delay the evaluation of the value by enclosing the node in quotes:
> 
> log "#{node["network_storage"]["attached_devices"]}"
> 
> This way instead of being dereferenced during the compile phase (what's 
> happening now), it'll be evaluated during convergence.
> 
> See http://pastie.org/5522742 for a test of this.
> 
> -Peter
> 
> 
> 
> 
> On Thu, Dec 13, 2012 at 7:13 PM, Cary Penniman 
> <
 >
>  wrote:
> Is there a best practice to pass values from generated in one resource to 
> another?  
> 
> My example: 
> 
> I have a LWRP that attaches a cloudstack-kvm volume (think EBS volume), but 
> the device name the volume gets attached to cannot be specified in the 
> 'attach' api call, just discovered on the vm after the attach.  What is the 
> best way to pass that device_name value (discovered at converge time) to 
> another resource (e.g. mount or filesystem or lvm)?
> 
> The problem:
> 
> I assumed setting a node attribute would be the best way, but the attribute 
> value I want is set during the converge phase, and the resource attributes 
> are evaluated at compile time, so that alone doesn't work.  Here is an 
> cookbook snippet that distills my dilemma:
> 
> http://pastie.org/5522594
> 
> Looking at the pastie snippet, what is the best way to pass the value set 
> in the ruby_block to the log resource in the recipe? 
> 
> -Cary P
>