Cobler module for Chef

register_chef.py

"""
(C) 2010 Pragmatic Source
Farzad FARID <[email protected]>

register_chef.py: Register the server being installed on the Chef server
We assume that the 'knife' is installed locally on the Cobbler server.

Check https://fedorahosted.org/cobbler/wiki/CobblerTriggers for
documentation on Cobbler's triggers and API.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301  USA
"""

import utils
import sys
import os


# Configuration settings
# ----------------------

# * home:
#       The HOME environment variable is undefined in the cobblerd process, we
#       have to set it here for 'knife' to be able to find its configuration
#       file, '~/.chef/knife.rb'.
# * knife_config_path:
#       If the 'knife.rb' configuration file is in an unusual place, define the
#       full path here.
# * chef_roles:
#       List of compulsory Chef Roles to prepend to the management classes extracted
#       from the Cobbler configuration.
# Only the 'home' setting is compulsory.
CHEF_CONFIG = { 
    #'home': '/root',
    'knife_config_path': '/root/.chef/knife.rb',
    'chef_roles': [ 'Linux' ]
    }


def register():
    # this pure python trigger acts as if it were a legacy shell-trigger, but is much faster.
    # the return of this method indicates the trigger type
    return "/var/lib/cobbler/triggers/install/post/*"

def run(api, args, logger):
    objtype = args[0] # "system" or "profile"
    name    = args[1] # name of system or profile
    boot_ip = args[2] # ip or "?"

    # Handle only systems, not profiles
    if objtype != "system":
        return 0

    # Lookup the node in Cobbler's database
    node = api.find_system(name)

    # Find its fully qualified hostname and the management classes, to which we
    # add "Linux" unconditionnaly. We directly map cobbler's Management Classes to
    # Chef Roles' names.
    hostname = node.hostname
    roles = node.mgmt_classes
    roles = CHEF_CONFIG.get('chef_roles', []) + roles

    logger.info("Registering %s (%s) in Chef" % (name, hostname))

    # Create the node in Chef, deleting it first if necessary, and
    # add roles one by one.
    # Note: "knife node delete" does not destroy the node's RSA key. We don't
    # need to delete it as it will be recreated by chef-client on the first
    # run.
    if CHEF_CONFIG.has_key('home'):
        os.environ['HOME'] = CHEF_CONFIG['home']
    knife_opts = ''
    if CHEF_CONFIG.has_key('knife_config_path'):
        knife_opts = '--config ' + CHEF_CONFIG['knife_config_path']

    # Delete the node
    # Ignore stderr too, as usually this command should fail.
    rc = utils.subprocess_call(logger, 
            "knife node delete %(hostname)s --yes %(knife_opts)s >/dev/null 2>&1" % { 'hostname': hostname, 'knife_opts': knife_opts }, 
            shell=True)
    if rc != 0:
        logger.warning("Failed to delete node %s in Chef" % hostname)
    # Add the node
    rc = utils.subprocess_call(logger, "knife node create %(hostname)s --no-editor %(knife_opts)s >/dev/null" % 
            { 'hostname': hostname, 'knife_opts': knife_opts},
            shell=True)
    if rc != 0:
        logger.error("Failed to create node %s in Chef" % hostname)
    # Add roles to the node
    for role in roles:
        rc = utils.subprocess_call(logger, 
                "knife node run_list add %(hostname)s \"role[%(role)s]\" %(knife_opts)s >/dev/null" % { 'hostname': hostname, 'knife_opts': knife_opts, 'role': role },
                shell=True)
        if rc != 0:
            logger.error("Failed to add role %(role)s to node %(hostname)s in Chef" % { 'hostname': hostname, 'role': role })

    return 0