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 OMF 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 # given that we're now responsible for fetching this one, I have to
  45 # decide on an actual path - not jsut a name to search for in PATH
  46 omf_rc_trigger_script="/usr/bin/plc_trigger_omf_rc"
  47
  48 # hopefully temporary: when trigger script is missing, fetch it at the url here
  49 omf_rc_trigger_url="http://git.mytestbed.net/?p=omf.git;a=blob_plain;f=omf_rc/bin/plc_trigger_omf_rc;hb=HEAD"
  50 def fetch_trigger_script_if_missing (slicename):
  51     full_path="/vservers/%s/%s"%(slicename,omf_rc_trigger_script)
  52     if not os.path.isfile (full_path):
  53         retcod=subprocess.call (['curl','--silent','-o',full_path,omf_rc_trigger_url])
  54         if retcod!=0:
  55             logger.log("Could not fetch %s"%omf_rc_trigger_url)
  56         else:
  57             subprocess.call(['chmod','+x',full_path])
  58             logger.log("omf_resctl: fetched %s"%(full_path))
  59             logger.log("omf_resctl: from %s"%(omf_rc_trigger_url))
  60
  61 def GetSlivers(data, conf = None, plc = None):
  62     logger.log("omf_resctl.GetSlivers")
  63     if 'accounts' not in data:
  64         logger.log_missing_data("omf_resctl.GetSlivers",'accounts')
  65         return
  66
  67     try:
  68         xmpp_server=data['xmpp']['server']
  69         if not xmpp_server:
  70             # we have the key but no value, just as bad
  71             raise Exception
  72     except:
  73         # disabled feature - bailing out
  74         logger.log("omf_resctl: PLC_OMF config unsufficient (not enabled, or no server set), -- plugin exiting")
  75         return
  76
  77     hostname = data['hostname']
  78
  79     def is_omf_friendly (sliver):
  80         for chunk in sliver['attributes']:
  81             if chunk['tagname']=='omf_control': return True
  82
  83     for sliver in data['slivers']:
  84         # skip non OMF-friendly slices
  85         if not is_omf_friendly (sliver): continue
  86         slicename=sliver['name']
  87         yaml_template = config_ple_template
  88         yaml_contents = yaml_template\
  89             .replace('_xmpp_server_',xmpp_server)\
  90             .replace('_slicename_',slicename)\
  91             .replace('_hostname_',hostname)
  92         yaml_full_path="/vservers/%s/%s"%(slicename,yaml_slice_path)
  93         yaml_full_dir=os.path.dirname(yaml_full_path)
  94         if not os.path.isdir(yaml_full_dir):
  95             try: os.makedirs(yaml_full_dir)
  96             except OSError: pass
  97
  98         config_changes=tools.replace_file_with_string(yaml_full_path,yaml_contents)
  99         logger.log("yaml_contents length=%d, config_changes=%r"%(len(yaml_contents),config_changes))
 100         # would make sense to also check for changes to authorized_keys
 101         # would require saving a copy of that some place for comparison
 102         # xxx todo
 103         keys_changes = False
 104         if config_changes or keys_changes:
 105             # instead of restarting the service we call a companion script
 106             try:
 107                 fetch_trigger_script_if_missing (slicename)
 108                 # the trigger script actually needs to be run in the slice context of course
 109                 slice_command = [ "sudo", "-i",  omf_rc_trigger_script ]
 110                 to_run = tools.command_in_slice (slicename, slice_command)
 111                 logger.log("command_in_slice: %s"%to_run)
 112                 sp=subprocess.Popen(to_run, stdout=subprocess.PIPE,stderr=subprocess.STDOUT)
 113                 (out,err)=sp.communicate()
 114                 retcod=sp.returncode
 115                 # we don't wait for that, try to display a retcod for info purpose only
 116                 # might be None if that config script lasts or hangs whatever
 117                 logger.log("omf_resctl: %s: called OMF rc control script (imm. retcod=%r)"%(slicename,retcod))
 118                 logger.log("omf_resctl: got stdout\n%s"%out)
 119                 logger.log("omf_resctl: got stderr\n%s"%err)
 120             except:
 121                 import traceback
 122                 traceback.print_exc()
 123                 logger.log_exc("omf_resctl: WARNING: Could not call trigger script %s"%\
 124                                    omf_rc_trigger_script, name=slicename)
 125         else:
 126             logger.log("omf_resctl: %s: omf_control'ed sliver has no change" % slicename)