Customizing the templates of a community cookbook?

Chef Infra (archive)
1

What’s the “right” way to handle this? I’m looking to migrate over to using
Berkshelf and something that I’m coming across is that I’ve got a package
or two where I’ve customized the templates generated by a community
cookbook for my specific use (either via OS or host directories).

Is it better to create a wrapper cookbook, or is there some other way to
handle this that I’m missing? I found a previous thread on this here:
http://lists.opscode.com/sympa/arc/chef/2012-07/msg00038.html, but it looks
like whatever scenario they were referencing is no longer in the
documentation. (Not sure if it didn’t last from the wiki -> doc conversion,
or if it had been removed from the wiki prior to that.)

Thanks!

–
~~ StormeRider ~~

“Every world needs its heroes […] They inspire us to be better than we
are. And they protect from the darkness that’s just around the corner.”

(from Smallville Season 6x1: “Zod”)

On why I hate the phrase “that’s so lame”… http://bit.ly/Ps3uSS

2

On Sun, May 26, 2013 at 1:24 PM, Morgan Blackthorne
stormerider@gmail.comwrote:

What's the "right" way to handle this? I'm looking to migrate over to
using Berkshelf and something that I'm coming across is that I've got a
package or two where I've customized the templates generated by a community
cookbook for my specific use (either via OS or host directories).

Is it better to create a wrapper cookbook, or is there some other way to
handle this that I'm missing? I found a previous thread on this here:
chef - [chef] Re: How to override the source erb template from another custom cookbook?, but it
looks like whatever scenario they were referencing is no longer in the
documentation. (Not sure if it didn't last from the wiki -> doc conversion,
or if it had been removed from the wiki prior to that.)

I was able to load the old page using the wayback machine (
Templates - Chef - Opscode Open Source Wiki),
but it isn't too helpful in this case.

You'll need a wrapper cookbook which contains your local template, with a
recipe that re-opens the resource in the original cookbook and changes its
"cookbook" parameter to point to your wrapper cookbook. Joshua Timberman
has a blog post describing this, though his example is changing service
resources:

http://jtimberman.housepub.org/blog/2012/11/19/chef-repository-berkshelf-conversion/

If you'd prefer a little sugar, the chef-rewind gem offers your exact use
case as an example: GitHub - bryanwb/chef-rewind: monkeypatch chef to edit existing resources in place

Hope that helps,

Zac

3

Actually, that's exactly what I was looking for-- thanks! His OpenVPN
example is dead-on for what I need to do for nagios::server.

adds Joshua's blog to their Feedly list, after the Nth time of finding
something useful on it :slight_smile:

--
~~ StormeRider ~~

"Every world needs its heroes [...] They inspire us to be better than we
are. And they protect from the darkness that's just around the corner."

(from Smallville Season 6x1: "Zod")

On why I hate the phrase "that's so lame"... http://bit.ly/Ps3uSS

On Sun, May 26, 2013 at 5:40 AM, Zac Stevens zts@cryptocracy.com wrote:

On Sun, May 26, 2013 at 1:24 PM, Morgan Blackthorne <stormerider@gmail.com

wrote:

What's the "right" way to handle this? I'm looking to migrate over to
using Berkshelf and something that I'm coming across is that I've got a
package or two where I've customized the templates generated by a community
cookbook for my specific use (either via OS or host directories).

Is it better to create a wrapper cookbook, or is there some other way to
handle this that I'm missing? I found a previous thread on this here:
chef - [chef] Re: How to override the source erb template from another custom cookbook?, but it
looks like whatever scenario they were referencing is no longer in the
documentation. (Not sure if it didn't last from the wiki -> doc conversion,
or if it had been removed from the wiki prior to that.)

I was able to load the old page using the wayback machine (
Templates - Chef - Opscode Open Source Wiki), but it isn't too helpful in this case.

You'll need a wrapper cookbook which contains your local template, with a
recipe that re-opens the resource in the original cookbook and changes its
"cookbook" parameter to point to your wrapper cookbook. Joshua Timberman
has a blog post describing this, though his example is changing service
resources:

http://jtimberman.housepub.org/blog/2012/11/19/chef-repository-berkshelf-conversion/

If you'd prefer a little sugar, the chef-rewind gem offers your exact use
case as an example: GitHub - bryanwb/chef-rewind: monkeypatch chef to edit existing resources in place

Hope that helps,

Zac

4

Hi,

I used to use chef-rewind until I got the tip form Joshua to just access
the resource collection via resources().

So, I'd be interested in what's the benefit of the chef-rewind gem?

Thanks for explaining
Steffen

On 5/26/13 2:40 PM, Zac Stevens wrote:

On Sun, May 26, 2013 at 1:24 PM, Morgan Blackthorne
stormerider@gmail.comwrote:

What's the "right" way to handle this? I'm looking to migrate over to
using Berkshelf and something that I'm coming across is that I've got a
package or two where I've customized the templates generated by a community
cookbook for my specific use (either via OS or host directories).

Is it better to create a wrapper cookbook, or is there some other way to
handle this that I'm missing? I found a previous thread on this here:
chef - [chef] Re: How to override the source erb template from another custom cookbook?, but it
looks like whatever scenario they were referencing is no longer in the
documentation. (Not sure if it didn't last from the wiki -> doc conversion,
or if it had been removed from the wiki prior to that.)

I was able to load the old page using the wayback machine (
Templates - Chef - Opscode Open Source Wiki),
but it isn't too helpful in this case.

You'll need a wrapper cookbook which contains your local template, with a
recipe that re-opens the resource in the original cookbook and changes its
"cookbook" parameter to point to your wrapper cookbook. Joshua Timberman
has a blog post describing this, though his example is changing service
resources:

http://jtimberman.housepub.org/blog/2012/11/19/chef-repository-berkshelf-conversion/

If you'd prefer a little sugar, the chef-rewind gem offers your exact use
case as an example: GitHub - bryanwb/chef-rewind: monkeypatch chef to edit existing resources in place

Hope that helps,

Zac

5

This should also serve as a call to folks to make the templates used an
attribute where possible/where it makes sense:

https://github.com/lusis/chef-logstash/blob/master/attributes/kibana.rb#L3

On Sun, May 26, 2013 at 8:40 AM, Zac Stevens zts@cryptocracy.com wrote:

On Sun, May 26, 2013 at 1:24 PM, Morgan Blackthorne <stormerider@gmail.com

wrote:

What's the "right" way to handle this? I'm looking to migrate over to
using Berkshelf and something that I'm coming across is that I've got a
package or two where I've customized the templates generated by a community
cookbook for my specific use (either via OS or host directories).

Is it better to create a wrapper cookbook, or is there some other way to
handle this that I'm missing? I found a previous thread on this here:
chef - [chef] Re: How to override the source erb template from another custom cookbook?, but it
looks like whatever scenario they were referencing is no longer in the
documentation. (Not sure if it didn't last from the wiki -> doc conversion,
or if it had been removed from the wiki prior to that.)

I was able to load the old page using the wayback machine (
Templates - Chef - Opscode Open Source Wiki), but it isn't too helpful in this case.

You'll need a wrapper cookbook which contains your local template, with a
recipe that re-opens the resource in the original cookbook and changes its
"cookbook" parameter to point to your wrapper cookbook. Joshua Timberman
has a blog post describing this, though his example is changing service
resources:

http://jtimberman.housepub.org/blog/2012/11/19/chef-repository-berkshelf-conversion/

If you'd prefer a little sugar, the chef-rewind gem offers your exact use
case as an example: GitHub - bryanwb/chef-rewind: monkeypatch chef to edit existing resources in place

Hope that helps,

Zac

6

Hi Steffen,

On Sun, May 26, 2013 at 3:47 PM, Steffen Gebert st+gmane@st-g.de wrote:

I used to use chef-rewind until I got the tip form Joshua to just access
the resource collection via resources().

So, I'd be interested in what's the benefit of the chef-rewind gem?

Functionally, there's no benefit/difference - it's just a little "syntactic
sugar". Some people may prefer chef-rewind's syntax, even when they know
how to do it directly. Similarly, ruby-averse Chef users may find it a
little easier to use; a shallower learning curve makes a big difference in
some teams.

Zac

7

So after some more research, it looks like my particular case is a little
more complicated than I thought. While the nagios::server recipe ends up
using templates in the end, these are done via the nagios_conf definition:

define :nagios_conf, :variables => {}, :config_subdir => true do

conf_dir = params[:config_subdir] ? node['nagios']['config_dir'] :
node['nagios']['conf_dir']

template "#{conf_dir}/#{params[:name]}.cfg" do
owner node['nagios']['user']
group node['nagios']['group']
source "#{params[:name]}.cfg.erb"
mode 00644
variables params[:variables]
notifies :reload, "service[nagios]"
backup 0
end
end

I'm not sure how to override a definition.

--
~~ StormeRider ~~

"Every world needs its heroes [...] They inspire us to be better than we
are. And they protect from the darkness that's just around the corner."

(from Smallville Season 6x1: "Zod")

On why I hate the phrase "that's so lame"... http://bit.ly/Ps3uSS

On Sun, May 26, 2013 at 1:45 PM, Zac Stevens zts@cryptocracy.com wrote:

Hi Steffen,

On Sun, May 26, 2013 at 3:47 PM, Steffen Gebert st+gmane@st-g.de wrote:

I used to use chef-rewind until I got the tip form Joshua to just access
the resource collection via resources().

So, I'd be interested in what's the benefit of the chef-rewind gem?

Functionally, there's no benefit/difference - it's just a little
"syntactic sugar". Some people may prefer chef-rewind's syntax, even when
they know how to do it directly. Similarly, ruby-averse Chef users may
find it a little easier to use; a shallower learning curve makes a big
difference in some teams.

Zac

8

You have to override template[#{conf_dir}/#{params[:name]}.cfg]

On 5/27/13 4:25 PM, Morgan Blackthorne wrote:

So after some more research, it looks like my particular case is a little
more complicated than I thought. While the nagios::server recipe ends up
using templates in the end, these are done via the nagios_conf definition:

define :nagios_conf, :variables => {}, :config_subdir => true do

conf_dir = params[:config_subdir] ? node['nagios']['config_dir'] :
node['nagios']['conf_dir']

template "#{conf_dir}/#{params[:name]}.cfg" do
owner node['nagios']['user']
group node['nagios']['group']
source "#{params[:name]}.cfg.erb"
mode 00644
variables params[:variables]
notifies :reload, "service[nagios]"
backup 0
end
end

I'm not sure how to override a definition.

--
~~ StormeRider ~~

"Every world needs its heroes [...] They inspire us to be better than we
are. And they protect from the darkness that's just around the corner."

(from Smallville Season 6x1: "Zod")

On why I hate the phrase "that's so lame"... http://bit.ly/Ps3uSS

On Sun, May 26, 2013 at 1:45 PM, Zac Stevens zts@cryptocracy.com wrote:

Hi Steffen,

On Sun, May 26, 2013 at 3:47 PM, Steffen Gebert st+gmane@st-g.de wrote:

I used to use chef-rewind until I got the tip form Joshua to just access
the resource collection via resources().

So, I'd be interested in what's the benefit of the chef-rewind gem?

Functionally, there's no benefit/difference - it's just a little
"syntactic sugar". Some people may prefer chef-rewind's syntax, even when
they know how to do it directly. Similarly, ruby-averse Chef users may
find it a little easier to use; a shallower learning curve makes a big
difference in some teams.

Zac