How to use the python LWRP with Opsworks/Chef 11

Question

I am new to Chef/OpsWorks and am attempting a simple recipe to install Django 1.6 on an Ubuntu 12.04 instance:

python_pip "Django" do
    version "1.6"
    action :install
end

My providers/pip.rb and providers/virtualenv.rb seem to override what, ostensibly, was already loaded:

DEBUG: Loading cookbook python's providers from /opt/aws/opsworks/releases/20131107153140_213/site-cookbooks/python/providers/pip.rb

DEBUG: Loaded contents of /opt/aws/opsworks/releases/20131107153140_213/site-cookbooks/python/providers/pip.rb into a provider named python_pip defined in Chef::Provider::PythonPip

DEBUG: Loading cookbook python's providers from /opt/aws/opsworks/releases/20131107153140_213/site-cookbooks/python/providers/virtualenv.rb

DEBUG: Loaded contents of /opt/aws/opsworks/releases/20131107153140_213/site-cookbooks/python/providers/virtualenv.rb into a provider named python_virtualenv defined in Chef::Provider::PythonVirtualenv

DEBUG: Loading cookbook python's providers from /opt/aws/opsworks/releases/20131107153140_213/site-cookbooks/python/providers/pip.rb

INFO: PythonPip light-weight provider already initialized -- overriding!

DEBUG: Loaded contents of /opt/aws/opsworks/releases/20131107153140_213/site-cookbooks/python/providers/pip.rb into a provider named python_pip defined in Chef::Provider::PythonPip

DEBUG: Loading cookbook python's providers from /opt/aws/opsworks/releases/20131107153140_213/site-cookbooks/python/providers/virtualenv.rb

INFO: PythonVirtualenv light-weight provider already initialized -- overriding!

But when I try to use python_pip I receive an error:

ERROR: Caught exception while compiling OpsWorks custom run list: NameError - Cannot find a resource for python_pip on ubuntu version 12.04 

I've tried adding depends "python" in my metadata.rb, but this did not help. Any suggestions are appreciated.

My directory structure of my cookbook 'python':

.
├── python
│   ├── attributes
│   │   └── default.rb
│   ├── metadata.rb
│   ├── providers
│   │   ├── pip.rb
│   │   └── virtualenv.rb
│   ├── recipes
│   │   ├── default.rb
│   │   ├── django.rb
│   │   ├── package.rb
│   │   ├── pip.rb
│   │   ├── source.rb
│   │   └── virtualenv.rb
│   ├── specs
│   │   └── configure_spec.rb
│   └── templates
│       └── default
└── README.md

Answer 1

Don't try to modify the python cookbook unless it doesn't already do what you need. Your cookbooks directory should at minimum look like:

cookbooks/
    ├─python/ <clone of https://github.com/poise/python>
    |
    └─application_cookbook/
        ├─recipes/
        |   └─default.rb <containing the resource declaration you have in the question>
        └─metadata.rb <with a `depends "python"` statement in it>

That's it, no need to modify the python cookbook. Now just set your runlist to [ "python", "application_cookbook" ] and you're good to go.

Answer 2

Before you can use the python_pip LWRP, you need to either have python in your runlist or include_recipe "python" within your own recipe.

Here's an example that assumes you have a user named dj with a home directory already set up.

# Note that the recipe will install Python, setuptools and pip
include_recipe "python"


# Create a virtual environment
python_virtualenv '/home/dj/virtenv' do
   interpreter "python2.7"
   owner 'dj'
   group 'dj'
   action :create
end

# Install Django to a virtualenv
python_pip "django" do
   virtualenv '/home/dj/virtenv'
   user 'dj'
   group 'dj'
   action :install
end