[chef] Re: PostgreSQL cookbook questions / issues

[Daniel DeLeo < >]

On Thursday, May 16, 2013 at 5:39 PM, Jeffrey Jones wrote:

Hello all,

I have been messing around with Chef this week with a view to using it to manage our Linux servers.

Generally things have been going well but I have run into a few problems which I would like to ask more experienced chef'ers (Is there a proper term for chef users?) about.

My goal is to install PostgreSQL 9.2 on CentOS 6.4. I wish to use the "Database" cookbook to manage parts of the database therefore I need to install the pg gem in chef. To this end I have the following .json file and "master" cookbook recipe: https://gist.github.com/rurounijones/5596193

After much trial and tribulation I have managed to get PostgreSQL installed BUT I have had to modify various recipes in the PostgreSQL cookbook which seems...strange since I cannot believe I am the first person who has tried the above.

Therefore I would like to ask if anyone can comment on the following and let me know if I am missing something:

1) PostgreSQL 9.2 on CentOS 6.4

As far as I can tell, using opscode's cookbook it is impossible to install anything other than PostgreSQL 8.4 on CentOS >= 6.0 without having t modify lots of things like package names, service names etc. I have submitted a pull request regarding this: https://github.com/opscode-cookbooks/postgresql/pull/59

Woot, thanks. Did you file a ticket on http://tickets.opscode.com/secure/Dashboard.jspa ? I know it feels redundant, but we use jira to keep track of what goes in each release and we got heavily invested in Jira before github had any features that met our needs. Creating a ticket on tickets.opscode.com and setting to "fix provided" with a link to your pull request will ensure your contribution comes up during code review meetings (these are held on G+ hangouts if you're interested in participating).

2) postgresql::ruby recipe

There appears to be a redundant chunk of code in the postgresql::ruby recipe at https://github.com/opscode-cookbooks/postgresql/blob/master/recipes/ruby.rb#L33 which was causing me problems. The line in question installs the client packages but in the line right before it it includes the postgresl::client recipe which... installs the client packages. I had various problems with this chunk of code as it appeared to be running before the postgresql::client code which resulted in it trying to install the packages before the pgdg repository had been enabled. Removing the package installation code from this file solved the issue.

The code there is forcing the packages to get installed during the cookbook compile phase so the C library deps of the pg gem are available when the gem gets installed, which is itself required to be available early for database resources to work. It may be possible to rework the cookbook to avoid this hackery, I'm not too familiar with it so I can't say.

 

3) No libpqxx-devel

On all CentOS systems I have ever set-up with ruby and the pg gem I have needed to install the libpqxx-devel library. However I can see no mention of this package in any of the PostgreSQL chef scripts, I am therefore puzzled how this has worked up until now, in my copy of the cookbook I added this to the client packages.

4) Installing the pg gem itself.

In relation to the above, on all CentOS systems I have ever used with the libpqxx-devel library I have had to include the pg bin into the PATH so that, during installation, the pg gem can find the pg_config binary.

The pg gem installation code in the https://github.com/opscode-cookbooks/postgresql/blob/master/recipes/ruby.rb is pretty complex, and do be honest, I am not entirely sure what it is doing. However, on a CentOS 6.4 install I was never able to get this working (I am afraid I did not save the error message, apologies). What I did instead was replace the chef_gem method (https://github.com/opscode-cookbooks/postgresql/blob/master/recipes/ruby.rb#L40) with
the following:

    bash 'install_chef_pg_gem' do
      code <<-EOH
        PATH=$PATH:/usr/pgsql-9.2/bin /opt/chef/embedded/bin/gem install pg
      EOH
    end

It may not be pretty but it works for me (caveat emptor).

IIRC, in some cases there have been conflicts between the OpenSSL included with the omnibus package (that is linked by the embedded ruby) and the one installed from packages. That code is a bunch of hackery to workaround the issue. Again, I'm not personally familiar with the constraints on the solution.

 

Now as I said before, with the above modifications, I have managed to install PostgreSQL, setup database management etc. so I am quite happy but I am shocked that I had to make the above changes, it rather implies that I am "doing it wrong" or misunderstanding something.

What I would like is for a Chef'er to have a look at my findings and tell me if I am doing things wrong. If it IS possible to install PostgreSQL 9.2 on CentOS 6.4 with the pg gem installed into chef without having to modify the postgresql cookbook as I have done, would it be possible for some nice person to put up a sample of how it would be done?

(If you have Vagrant then I am using the following box: http://developer.nrel.gov/downloads/vagrant-boxes/CentOS-6.4-x86_64-v20130309.box )

Cheers,

Jeff

Hope you find that a bit helpful.

-- 

Daniel DeLeo