[chef] Re: Re: Re: Re: Re: Re: How to override node attribute with lazy value?

[Lamont Granquist < >]

How it should be written, i'll look at submitting a PR...

On Fri Oct  3 15:05:03 2014, Greg Barker wrote:
> Thanks for the additional responses. Unfortunately I still wasn't able
> to get it working.
>
> I put the following in my attributes/default.rb:
>
> default["chef-server"]["configuration"]["nginx"]["ssl_certificate"] =
> "/etc/pki/tls/certs/%{fqdn}.pem"
> default["chef-server"]["configuration"]["nginx"]["ssl_certificate_key"] =
> "/etc/pki/tls/private/%{fqdn}.key"
>
> Then in my recipe I have:
>
> node["chef-server"]["configuration"]["nginx"]["ssl_certificate"] % {
> fqdn: node[:fqdn] }
> node["chef-server"]["configuration"]["nginx"]["ssl_certificate_key"] %
> { fqdn: node[:fqdn] }
>
> include_recipe "chef-server::default"
>
> This resulted in a /var/opt/chef-server/nginx/etc/chef_https_lb.conf with:
>
> ssl_certificate /etc/pki/tls/certs/%{fqdn}.pem;
> ssl_certificate_key /etc/pki/tls/private/%{fqdn}.key;
>
> Which of course nginx did not like:
>
> 2014-10-03_21:59:37.09937 nginx: [emerg] directive "ssl_certificate"
> is not terminated by ";"
>
> I also tried setting those attributes in my role instead of the
> attributes/default.rb file:
>
> "configuration": {
>   "nginx": {
>     "ssl_certificate": "/etc/pki/tls/certs/%{fqdn}.pem",
>     "ssl_certificate_key": "/etc/pki/tls/private/%{fqdn}.key"
>    }
>  }
>
> This resulted in the same error.
>
> Lamont - I'm not sure I understand your response. Does that actually
> set the node["chef-server"]["configuration"]["nginx"][
> "ssl_certificate"] attribute that the chef-server cookbook is
> expecting? Or is that how the chef-server cookbook should have been
> written?
>
> Thanks,
> Greg
>
> On Fri, Oct 3, 2014 at 8:02 AM, Lamont Granquist 
> <
>  
> <mailto:
>  >>
>  wrote:
>
>
>     Just move that into a computation in recipe code that is stored in
>     a variable and not in a node attribute:
>
>     in default.rb:
>
>     ssl_certificate = node["chef-server"]["__configuration"]["nginx"][
>     "ssl_certificate"] ||=
>       "/etc/pki/tls/certs/%{node["__fqdn"]}.pem"
>
>     then don't set that attribute in the attribute file, leave it only
>     as a hook for someone to override the computation with.
>
>     See https://github.com/lamont-__granquist/erlang_one
>     <https://github.com/lamont-granquist/erlang_one> for an example
>     cookbook I wrote last night, with tests showing that you can wrap
>     the cookbook the way that people want to.  Works without computed
>     attributes directly in the attributes file, it exposes the kind of
>     behavior so that what the recipe does is computed from the input
>     attributes.  Since it uses a ruby variable instead of setting node
>     attributes in recipe code there's no attribute precedence issues.
>
>     On Fri Oct 3 07:21:32 2014, Christine Draper wrote:
>
>
>         Greg,
>
>         Using Noah's approach, you'd have something like this in your
>         attribute file, to establish the pattern for the derived
>         attribute:
>
>         node["chef-server"]["__configuration"]["nginx"][
>         "ssl_certificate"] =
>         "/etc/pki/tls/certs/%{fqdn}.__pem" }
>
>         And then this in your recipe where actually wanted to realize
>         the value:
>
>         node["chef-server"]["__configuration"]["nginx"][
>         "ssl_certificate"] % {
>         fqdn : node[:fqdn] }
>
>         Hope this helps.
>         Christine
>
>
>
>         "/etc/pki/tls/certs/#{node[:__fqdn]}.pem" }
>
>
>         On Thu, Oct 2, 2014 at 11:18 AM, Greg Barker
>         
> <
>  
>  
> <mailto:
>  >
>         
> <mailto:
>  
>         
> <mailto:
>  >>__>
>  wrote:
>
>         Thanks Noah. I tried it out but I don't think I'm doing it right.
>
>         node["chef-server"]["__configuration"]["nginx"] % {
>         ssl_certificate:
>         "/etc/pki/tls/certs/#{node[:__fqdn]}.pem" }
>
>         This resulted in:
>
>         NoMethodError - undefined method `%' for nil:NilClass
>
>         So before that line I added:
>
>         node.default["chef-server"]["__configuration"]["nginx"] = {}
>
>         But now I get the error:
>
>         NoMethodError - Undefined node attribute or method `%' on `node'
>
>         Any ideas?
>
>         On Thu, Oct 2, 2014 at 7:55 AM, Noah Kantrowitz
>         
> <
>  
>  
> <mailto:
>  >
>         
> <mailto:
>  
>  
> <mailto:
>  >>>
>  wrote:
>
>
>         On Oct 2, 2014, at 3:13 AM, Greg Barker 
> <
>  
>         
> <mailto:
>  >
>         
> <mailto:
>  
>         
> <mailto:
>  >>__>
>  wrote:
>
>         > The chef-server readme shows how to override nginx
>         attributes. However, it doesn't seem to work like I want it to
>         when I do:
>         >
>         >
>         
> node.override["chef-server"]["__configuration"]["nginx"]["ssl___certificate"]
>         = "/etc/pki/tls/certs/#{node[:__fqdn]}.pem"
>         >
>         > node[:fqdn] is being updated during my chef run using the
>         hostname cookbook, and so using the above results in an error
>         because chef-server ends up looking for
>         /etc/pki/tls/certs/localhost.__pem (the old hostname), when it
>         should instead be using
>         /etc/pki/tls/certs/mynode.__mycompany.com.pem.
>         >
>         > So I think I want something like the following, but this
>         doesn't work. What's the right way to do it?
>         >
>         >
>         
> node.override["chef-server"]["__configuration"]["nginx"]["ssl___certificate"]
>         = lazy { "/etc/pki/tls/certs/#{node[:__fqdn]}.pem" }
>
>         lazy{} is a feature of resources, not of node attributes. See
>         https://coderanger.net/__derived-attributes/
>         <https://coderanger.net/derived-attributes/> for more
>         information about how to handle delayed interpolation in node
>         attributes.
>
>         --Noah