[chef] Re: render partial template only if the node['fqdn']-partial exists

[Noah Kantrowitz < >]

I don't think this is currently possible without a lot of extra work. The 
complex way would be to look at the cookbook metadata in the cookbook 
collection to see what template files exist. This is definitely not how 
templates are intended to be used at present though.

--Noah

On May 12, 2014, at 12:13 PM, 

 
 wrote:

> 
> Hiya,
> 
> How can I render a base template *plus* a partial template only if the 
> partial
> exists for node['fqdn']? Is there a way to do this? The way I see it now, 
> the
> only way I can do this is to create a per-fqdn erb files in my cookbook for
> every host, even if only a few of them actually need to render the partial. 
> I'll
> bet there's a better way to do this, I just don't see it yet.
> 
> Let's say I have a bunch of mysql database hosts, and most of them can 
> render
> their my.cnf following one standard. And let's say sometimes I have a need 
> to
> extend the standard by appending extra config lines for only some of the db
> hosts.
> 
> Here are examples of the rendered my.cnf I want, the first is for a db host 
> that
> has no special config lines, the second for a db host that needs a lil 
> extra:
> 
>  [mysqld]
>  server-id = 14050101
>  report-host = db14b.dev.example.com
>  !include /etc/mysql/_my.cnf_m3.large
>  !include /etc/mysql/_my.cnf.global_5.5
> 
> 
>  [mysqld]
>  server-id = 14050701
>  report-host = db26b.dev.example.com
>  !include /etc/mysql/_my.cnf_m3.large
>  !include /etc/mysql/_my.cnf.global_5.5
>  #
>  # special stuff for this host is below, brought to you by chef partial 
> template:
>  [mysqld]
>  expire_logs_days=5
>  replicate-wild-ignore-table = foo_bar.KBToyAndHobby%
> 
> 
> The template resource in the recipe:
> 
>  template "/etc/mysql/my.cnf" do
>    source "my.cnf.erb"
>    owner "root"
>    group "root"
>    mode 00644
>    variables :server_id     => node['tokopf-bar']['mysql']['server_id'],
>              :mysql_version => node['tokopf-bar']['mysql']['mysql_version']
>  end
> 
> 
> The main template, my.cnf.erb:
>  [mysqld]
>  server-id = <%= @server_id %>
>  report-host = <%= node['fqdn'] %>
>  !include /etc/mysql/_my.cnf_<%= node['ec2']['instance_type'] %>
>  !include /etc/mysql/_my.cnf.global_<%= @mysql_version %>
>  <%= render @node['fqdn'] + ".mycnf-partial.erb" -%>
> 
> 
> cookbooks/tokopf-bar/templates/default/db14b.dev.example.com.mycnf-partial.erb
>  is empty...
> 
> cookbooks/tokopf-bar/templates/default/db26b.dev.example.com.mycnf-partial.erb:
>  #
>  # special stuff for this host is below, brought to you by chef partial 
> template:
>  [mysqld]
>  expire_logs_days=5
>  replicate-wild-ignore-table = foo_bar.KBToyAndHobby%
> 
> 
> Thanks!
> kallen
>

Attachment: signature.asc
Description: Message signed with OpenPGP using GPGMail