[chef] Re: application cookbook "annoyances"

[Joshua Timberman < >]

On Feb 5, 2013, at 10:54 PM, Torben Knerr 
<
 >
 wrote:

> The nagios cookbook allows to set role to search for in the search query 
> (default is "monitoring"), but it doesn't set the role of the node, does it?
> 
> If so, I wouldn't have to keep around marker roles as .rb files but would 
> set the node's role in the application cookbook instead.

No, it only sets what the query is going to use. Essentially:

    search(:node, "role:monitoring")

Or replace with whatever the attribute gets set, e.g.:

    node.set['nagios']['server_role'] = 'nagios_thing'

Results in this query:

    search(:node, "role:nagios_thing")

> > An argument could be made that the search should be for a node with the
> > appropriate recipe applied, but only recipes in the expanded run list (not
> > those from 'include_recipe' in another recipe)...
> >
> 
> Agree, but this having the problems described in 2) below...
> 
> I believe that there are valid use cases for both searches, so we'd ideally 
> find a way to handle both.
> 
> > They do not get appended to the "recipes" attribute. That has also been
> > discussed in the past:
> >
> > * http://tickets.opscode.com/browse/CHEF-1977
> 
> That's currently the dealbreaker for me. I added a comment and upvoted the 
> ticket.
> 
> In the meantime, is there any viable workaround other than patching the 
> cookbooks that use search 'recipe:...'?
> 
> E.g. would it be possible to set the "recipes" attribute from within the 
> application cookbook and would that be indexed for search then?

What about using an attribute on the server set via its appropriate recipe 
that indicates that it is the "server" component for clients to search?

We use this in our rsyslog cookbook.

Default value:

https://github.com/opscode-cookbooks/rsyslog/blob/master/attributes/default.rb#L21

Server recipe sets the attribute:

https://github.com/opscode-cookbooks/rsyslog/blob/master/recipes/server.rb#L22

Client searches for a node with the attribute:

https://github.com/opscode-cookbooks/rsyslog/blob/master/recipes/client.rb#L25-L26

This may not require any modification of the upstream cookbook on your part 
either. In your "application" cookbook, have a "server" recipe that sets the 
attribute. In the same cookbook, have a "client" recipe that performs the 
search. Using the Nagios example, the "server_role" is used for the nrpe.cfg 
file, so you could re-open the template and set mon_host appropriately.

# recipe[my-nagios::server]
node.set['nagios']['server'] = true

# recipe[my-nagios::client]
mon_host = search(:node, "nagios_server:true")
nrpecfg = 
resources("template[#{node['nagios']['nrpe']['conf_dir']}/nrpe.cfg]")
nrpecfg.variables(:mon_host => mon_host)

Cheers,
Joshua