Allow for the running after install and run arguments to be configured

Instead of only running the client when installed from gems, allow it
to be ran from other install modes as well (if configured) and allow the
arguments that are passed to the client when ran to be altered (if so
desired).

cloudinit/config/cc_chef.py

@@ -18,7 +18,6 @@
 #    You should have received a copy of the GNU General Public License
 #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from datetime import datetime
 import json
 import os
 
@@ -66,7 +65,7 @@ CHEF_RB_TPL_KEYS = frozenset(CHEF_RB_TPL_KEYS)
 CHEF_RB_PATH = '/etc/chef/client.rb'
 CHEF_FB_PATH = '/etc/chef/firstboot.json'
 CHEF_EXEC_PATH = '/usr/bin/chef-client'
-CHEF_EXEC_CMD = tuple([CHEF_EXEC_PATH, '-d', '-i', '1800', '-s', '20'])
+CHEF_EXEC_DEF_ARGS = tuple(['-d', '-i', '1800', '-s', '20'])
 
 
 def is_installed():
@@ -158,24 +157,42 @@ def handle(name, cfg, cloud, log, _args):
     force_install = util.get_cfg_option_bool(chef_cfg,
                                              'force_install', default=False)
     if not is_installed() or force_install:
-        run = install_chef(cloud, chef_cfg, log)
+        run_after = install_chef(cloud, chef_cfg, log)
-        if run:
+        if run_after:
             log.debug('Running chef-client')
-            util.subp(CHEF_EXEC_CMD, capture=False)
+            cmd = [CHEF_EXEC_PATH]
+            if 'exec_arguments' in chef_cfg:
+                cmd_args = chef_cfg['exec_arguments']
+                if isinstance(cmd_args, (list, tuple)):
+                    cmd.extend(cmd_args)
+                elif isinstance(cmd_args, (str, basestring)):
+                    cmd.append(cmd_args)
+                else:
+                    log.warn("Unknown type %s provided for chef"
+                             " 'exec_arguments' expected list, tuple,"
+                             " or string", type(cmd_args))
+                    cmd.extend(CHEF_EXEC_DEF_ARGS)
+            else:
+                cmd.extend(CHEF_EXEC_DEF_ARGS)
+            util.subp(cmd, capture=False)
 
 
 def install_chef(cloud, chef_cfg, log):
     # If chef is not installed, we install chef based on 'install_type'
     install_type = util.get_cfg_option_str(chef_cfg, 'install_type',
                                            'packages')
-    run_after = False
+    run_after = util.get_cfg_option_bool(chef_cfg, 'exec_after_install',
+                                         default=False)
     if install_type == "gems":
         # This will install and run the chef-client from gems
         chef_version = util.get_cfg_option_str(chef_cfg, 'version', None)
         ruby_version = util.get_cfg_option_str(chef_cfg, 'ruby_version',
                                                RUBY_VERSION_DEFAULT)
         install_chef_from_gems(cloud.distro, ruby_version, chef_version)
-        run_after = True
+        # Retain backwards compat, but preferring True instead of False
+        # when not provided/overriden...
+        run_after = util.get_cfg_option_bool(chef_cfg, 'exec_after_install',
+                                             default=True)
     elif install_type == 'packages':
         # This will install and run the chef-client from packages
         cloud.distro.install_packages(('chef',))
@@ -190,6 +207,7 @@ def install_chef(cloud, chef_cfg, log):
             util.subp([tmpf], capture=False)
     else:
         log.warn("Unknown chef install type '%s'", install_type)
+        run_after = False
     return run_after