Chef recipe to run gunicorn application and gearman workers. Posted for discussion about notification problems. This is probably not a good example to follow. :)

default.rb

#
# Cookbook Name:: imgmuck
# Recipe:: default
#
# Copyright 2012, Scaled Recognition, all rights reserved
#

include_recipe "git"
include_recipe "python"
include_recipe "application"
include_recipe "supervisor" 

directory "/srv/imgmuck/shared" do
    mode '0755'
    owner "nobody"
    group "nogroup"
    recursive true
end


supervisor_service "srapiworker" do
    action :enable
    autostart true
    user "nobody"
    process_name "srapiworker%(process_num)s"

    directory "/srv/imgmuck/current"
    command "python sr/pipeline/worker.py"
    numprocs node['apiserver']['numworkers']
    environment ({
        "PYTHONPATH" => "/srv/imgmuck/current"
    })
end


supervisor_service "imgmuck" do
    # Create a stub service so I can notify it.
    action :nothing
end


template "/srv/imgmuck/shared/local_serverconfig.py" do
    #TODO: Get address_list from a chef server search instead of data bag.
    address_list = data_bag_item('server_locations','gearmand_address')[node.chef_environment]
    if !address_list 
       raise NameError, "No gearmand address list found in environment #{node.chef_environment} in data bag #{data_bag_item('server_locations','gearmand_address')}."
    end
    source "local_serverconfig.py.erb"
    mode 0644
    owner "nobody"
    group "nogroup"
    variables({ 
        :gearmand_address => address_list
    })

    # Notify the running jobs that they need to restart with new config
    notifies :restart, "supervisor_service[srapiworker]", :immediate
    notifies :restart, "supervisor_service[imgmuck]", :immediate
end


application "imgmuck" do
    repository node['apiserver']['gitrepos']['imgmuck']
    revision node['apiserver']['gitbranches']['imgmuck']
    deploy_key data_bag_item('deploykeys','imgmuck')['deploy_key']

    path "/srv/imgmuck"
    owner "nobody"
    group "nogroup"

    gunicorn do
        app_module node['apiserver']['gunicorn']['app_module']
        port node['apiserver']['gunicorn']['port']
        workers node['apiserver']['gunicorn']['workers']
        timeout node['apiserver']['gunicorn']['timeout']
    end

    symlinks ({
        "local_serverconfig.py" => "local_serverconfig.py"
    })

    # Below are several unsuccessful attempts to notify the worker jobs to restart
    # on code pushes.  None of them seem to do anything.  Go figure.
    #
    #notifies :restart, "supervisor_service[srapiworker]" 
    #
    #before_restart do
    #    notifies :restart, "supervisor_service[srapiworker]"
    #end
    #    
    #after_restart do
    #    notifies :restart, "supervisor_service[srapiworker]"
    #end
end


supervisor_service "srapiworker" do
    action :nothing
    subscribes :restart, "deploy_revision[imgmuck]", :immediate
    # Note the :immediate is needed or else the action just gets swallowed.  Bizarre.
end