plugins/omf_resctl.py

   1 #
   2 # NodeManager plugin - first step of handling omf_controlled slices
   3 #
   4
   5 """
   6 Overwrites the 'resctl' tag of slivers controlled by OMF so slivermanager.py does the right thing
   7 """
   8
   9 import os, os.path
  10 import glob
  11 import subprocess
  12
  13 import tools
  14 import logger
  15
  16 priority = 50
  17
  18 def start():
  19     pass
  20
  21 ### the new template for v6
  22 # hard-wire this for now
  23 # once the variables are expanded, this is expected to go into
  24 config_ple_template="""---
  25 # Example:
  26 # _slicename_ = nicta_ruby
  27 # _hostname_ = planetlab1.research.nicta.com.au
  28 # _xmpp_server_ = xmpp.planet-lab.eu
  29
  30 :uid: _slicename_@_hostname_
  31 :uri: xmpp://_slicename_-_hostname_-<%= "#{Process.pid}" %>:_slicename_-_hostname_-<%= "#{Process.pid}" %>@_xmpp_server_
  32 :environment: production
  33 :debug: false
  34
  35 :auth:
  36   :root_cert_dir: /home/_slicename_/root_certs
  37   :entity_cert: /home/_slicename_/entity.crt
  38   :entity_key: /home/_slicename_/.ssh/id_rsa
  39 """
  40
  41 # the path where the config is expected from within the sliver
  42 yaml_slice_path="/etc/omf_rc/config.yml"
  43 # the path for the script that we call when a change occurs
  44 omf_rc_trigger_script="plc_trigger_omf_rc"
  45
  46 def GetSlivers(data, conf = None, plc = None):
  47     logger.log("omf_resctl.GetSlivers")
  48     if 'accounts' not in data:
  49         logger.log_missing_data("omf_resctl.GetSlivers",'accounts')
  50         return
  51
  52     try:
  53         xmpp_server=data['xmpp']['server']
  54         if not xmpp_server:
  55             # we have the key but no value, just as bad
  56             raise Exception
  57     except:
  58         # disabled feature - bailing out
  59         logger.log("omf_resctl: PLC_OMF config unsufficient (not enabled, or no server set), -- plugin exiting")
  60         return
  61
  62     hostname = data['hostname']
  63
  64     def is_omf_friendly (sliver):
  65         for chunk in sliver['attributes']:
  66             if chunk['tagname']=='omf_control': return True
  67
  68     for sliver in data['slivers']:
  69         # skip non OMF-friendly slices
  70         if not is_omf_friendly (sliver): continue
  71         slicename=sliver['name']
  72         yaml_template = config_ple_template
  73         yaml_contents = yaml_template\
  74             .replace('_xmpp_server_',xmpp_server)\
  75             .replace('_slicename_',slicename)\
  76             .replace('_hostname_',hostname)
  77         yaml_full_path="/vservers/%s/%s"%(slicename,yaml_slice_path)
  78         yaml_full_dir=os.path.dirname(yaml_full_path)
  79         if not os.path.isdir(yaml_full_dir):
  80             try: os.makedirs(yaml_full_dir)
  81             except OSError: pass
  82
  83         config_changes=tools.replace_file_with_string(yaml_full_path,yaml_contents)
  84         logger.log("yaml_contents length=%d, config_changes=%r"%(len(yaml_contents),config_changes))
  85         # would make sense to also check for changes to authorized_keys
  86         # would require saving a copy of that some place for comparison
  87         # xxx todo
  88         keys_changes = False
  89         if config_changes or keys_changes:
  90             # instead of restarting the service we call a companion script
  91             try:
  92                 # the trigger script actually needs to be run in the slice context of course
  93                 # xxx we might need to use
  94                 # slice_command=['bash','-l','-c',omf_rc_trigger_script]
  95                 slice_command = [omf_rc_trigger_script]
  96                 to_run = tools.command_in_slice (slicename, slice_command)
  97                 sp=subprocess.Popen(to_run, stdout=subprocess.PIPE,stderr=subprocess.STDOUT)
  98                 (out,err)=sp.communicate()
  99                 retcod=sp.returncode
 100                 # we don't wait for that, try to display a retcod for info purpose only
 101                 # might be None if that config script lasts or hangs whatever
 102                 logger.log("omf_resctl: %s: called OMF rc control script (imm. retcod=%r)"%(slicename,retcod))
 103                 logger.log("omf_resctl: got stdout\n%s"%out)
 104                 logger.log("omf_resctl: got stderr\n%s"%err)
 105             except:
 106                 import traceback
 107                 traceback.print_exc()
 108                 logger.log_exc("omf_resctl: WARNING: Could not call trigger script %s"%\
 109                                    omf_rc_trigger_script, name=slicename)
 110         else:
 111             logger.log("omf_resctl: %s: omf_control'ed sliver has no change" % slicename)