planetstack/observer/event_loop.py

   1 import os
   2 import imp
   3 import inspect
   4 import time
   5 import traceback
   6 import commands
   7 import threading
   8 import json
   9
  10 from datetime import datetime
  11 from collections import defaultdict
  12 from core.models import *
  13 from django.db.models import F, Q
  14 #from openstack.manager import OpenStackManager
  15 from openstack.driver import OpenStackDriver
  16 from util.logger import Logger, logging, logger
  17 #from timeout import timeout
  18 from planetstack.config import Config
  19 from observer.steps import *
  20 from syncstep import SyncStep
  21 from toposort import toposort
  22
  23 debug_mode = False
  24
  25 logger = Logger(level=logging.INFO)
  26
  27 class StepNotReady(Exception):
  28         pass
  29
  30 class NoOpDriver:
  31         def __init__(self):
  32                  self.enabled = True
  33
  34 class PlanetStackObserver:
  35         #sync_steps = [SyncNetworks,SyncNetworkSlivers,SyncSites,SyncSitePrivileges,SyncSlices,SyncSliceMemberships,SyncSlivers,SyncSliverIps,SyncExternalRoutes,SyncUsers,SyncRoles,SyncNodes,SyncImages,GarbageCollector]
  36         sync_steps = []
  37
  38         def __init__(self):
  39                 # The Condition object that gets signalled by Feefie events
  40                 self.step_lookup = {}
  41                 self.load_sync_step_modules()
  42                 self.load_sync_steps()
  43                 self.event_cond = threading.Condition()
  44
  45
  46                 self.driver_kind = getattr(Config(), "observer_driver", "openstack")
  47                 if self.driver_kind=="openstack":
  48                         self.driver = OpenStackDriver()
  49                 else:
  50                         self.driver = NoOpDriver()
  51
  52         def wait_for_event(self, timeout):
  53                 self.event_cond.acquire()
  54                 self.event_cond.wait(timeout)
  55                 self.event_cond.release()
  56
  57         def wake_up(self):
  58                 logger.info('Wake up routine called. Event cond %r'%self.event_cond)
  59                 self.event_cond.acquire()
  60                 self.event_cond.notify()
  61                 self.event_cond.release()
  62
  63         def load_sync_step_modules(self, step_dir=None):
  64                 if step_dir is None:
  65                         if hasattr(Config(), "observer_steps_dir"):
  66                                 step_dir = Config().observer_steps_dir
  67                         else:
  68                                 step_dir = "/opt/planetstack/observer/steps"
  69
  70                 for fn in os.listdir(step_dir):
  71                         pathname = os.path.join(step_dir,fn)
  72                         if os.path.isfile(pathname) and fn.endswith(".py") and (fn!="__init__.py"):
  73                                 module = imp.load_source(fn[:-3],pathname)
  74                                 for classname in dir(module):
  75                                         c = getattr(module, classname, None)
  76
  77                                         # make sure 'c' is a descendent of SyncStep and has a
  78                                         # provides field (this eliminates the abstract base classes
  79                                         # since they don't have a provides)
  80
  81                                         if inspect.isclass(c) and issubclass(c, SyncStep) and hasattr(c,"provides") and (c not in self.sync_steps):
  82                                                 self.sync_steps.append(c)
  83                 logger.info('loaded sync steps: %s' % ",".join([x.__name__ for x in self.sync_steps]))
  84                 # print 'loaded sync steps: %s' % ",".join([x.__name__ for x in self.sync_steps])
  85
  86         def load_sync_steps(self):
  87                 dep_path = Config().observer_dependency_graph
  88                 logger.info('Loading model dependency graph from %s' % dep_path)
  89                 try:
  90                         # This contains dependencies between records, not sync steps
  91                         self.model_dependency_graph = json.loads(open(dep_path).read())
  92                 except Exception,e:
  93                         raise e
  94
  95                 try:
  96                         backend_path = Config().observer_pl_dependency_graph
  97                         logger.info('Loading backend dependency graph from %s' % backend_path)
  98                         # This contains dependencies between backend records
  99                         self.backend_dependency_graph = json.loads(open(backend_path).read())
 100                 except Exception,e:
 101                         logger.info('Backend dependency graph not loaded')
 102                         # We can work without a backend graph
 103                         self.backend_dependency_graph = {}
 104
 105                 provides_dict = {}
 106                 for s in self.sync_steps:
 107                         self.step_lookup[s.__name__] = s
 108                         for m in s.provides:
 109                                 try:
 110                                         provides_dict[m.__name__].append(s.__name__)
 111                                 except KeyError:
 112                                         provides_dict[m.__name__]=[s.__name__]
 113
 114
 115                 step_graph = {}
 116                 for k,v in self.model_dependency_graph.iteritems():
 117                         try:
 118                                 for source in provides_dict[k]:
 119                                         for m in v:
 120                                                 try:
 121                                                         for dest in provides_dict[m]:
 122                                                                 # no deps, pass
 123                                                                 try:
 124                                                                         if (dest not in step_graph[source]):
 125                                                                                 step_graph[source].append(dest)
 126                                                                 except:
 127                                                                         step_graph[source]=[dest]
 128                                                 except KeyError:
 129                                                         pass
 130
 131                         except KeyError:
 132                                 pass
 133                                 # no dependencies, pass
 134
 135                 #import pdb
 136                 #pdb.set_trace()
 137                 if (self.backend_dependency_graph):
 138                         backend_dict = {}
 139                         for s in self.sync_steps:
 140                                 for m in s.serves:
 141                                         backend_dict[m]=s.__name__
 142
 143                         for k,v in backend_dependency_graph.iteritems():
 144                                 try:
 145                                         source = backend_dict[k]
 146                                         for m in v:
 147                                                 try:
 148                                                         dest = backend_dict[m]
 149                                                 except KeyError:
 150                                                         # no deps, pass
 151                                                         pass
 152                                                 step_graph[source]=dest
 153
 154                                 except KeyError:
 155                                         pass
 156                                         # no dependencies, pass
 157
 158                 dependency_graph = step_graph
 159
 160                 self.ordered_steps = toposort(dependency_graph, map(lambda s:s.__name__,self.sync_steps))
 161                 print "Order of steps=",self.ordered_steps
 162                 self.load_run_times()
 163
 164
 165         def check_duration(self, step, duration):
 166                 try:
 167                         if (duration > step.deadline):
 168                                 logger.info('Sync step %s missed deadline, took %.2f seconds'%(step.name,duration))
 169                 except AttributeError:
 170                         # S doesn't have a deadline
 171                         pass
 172
 173         def update_run_time(self, step):
 174                 self.last_run_times[step.__name__]=time.time()
 175
 176         def check_schedule(self, step):
 177                 time_since_last_run = time.time() - self.last_run_times.get(step.__name__, 0)
 178                 try:
 179                         if (time_since_last_run < step.requested_interval):
 180                                 raise StepNotReady
 181                 except AttributeError:
 182                         logger.info('Step %s does not have requested_interval set'%step.__name__)
 183                         raise StepNotReady
 184
 185         def load_run_times(self):
 186                 try:
 187                         jrun_times = open('/tmp/observer_run_times').read()
 188                         self.last_run_times = json.loads(jrun_times)
 189                 except:
 190                         self.last_run_times={}
 191                         for e in self.ordered_steps:
 192                                 self.last_run_times[e]=0
 193
 194
 195         def save_run_times(self):
 196                 run_times = json.dumps(self.last_run_times)
 197                 open('/tmp/observer_run_times','w').write(run_times)
 198
 199         def check_class_dependency(self, step, failed_steps):
 200                 step.dependenices = []
 201                 for obj in step.provides:
 202                         step.dependenices.extend(self.model_dependency_graph.get(obj.__name__, []))
 203                 for failed_step in failed_steps:
 204                         if (failed_step in step.dependencies):
 205                                 raise StepNotReady
 206
 207         def run(self):
 208                 if not self.driver.enabled:
 209                         return
 210                 if (self.driver_kind=="openstack") and (not self.driver.has_openstack):
 211                         return
 212
 213                 while True:
 214                         try:
 215                                 logger.info('Waiting for event')
 216                                 tBeforeWait = time.time()
 217                                 self.wait_for_event(timeout=30)
 218                                 logger.info('Observer woke up')
 219
 220                                 # Set of whole steps that failed
 221                                 failed_steps = []
 222
 223                                 # Set of individual objects within steps that failed
 224                                 failed_step_objects = set()
 225
 226                                 for S in self.ordered_steps:
 227                                         step = self.step_lookup[S]
 228                                         start_time=time.time()
 229
 230                                         sync_step = step(driver=self.driver)
 231                                         sync_step.__name__ = step.__name__
 232                                         sync_step.dependencies = []
 233                                         try:
 234                                                 mlist = sync_step.provides
 235
 236                                                 for m in mlist:
 237                                                         sync_step.dependencies.extend(self.model_dependency_graph[m.__name__])
 238                                         except KeyError:
 239                                                 pass
 240                                         sync_step.debug_mode = debug_mode
 241
 242                                         should_run = False
 243                                         try:
 244                                                 # Various checks that decide whether
 245                                                 # this step runs or not
 246                                                 self.check_class_dependency(sync_step, failed_steps) # dont run Slices if Sites failed
 247                                                 self.check_schedule(sync_step) # dont run sync_network_routes if time since last run < 1 hour
 248                                                 should_run = True
 249                                         except StepNotReady:
 250                                                 logging.info('Step not ready: %s'%sync_step.__name__)
 251                                                 failed_steps.append(sync_step)
 252                                         except Exception,e:
 253                                                 logging.error('%r',e)
 254                                                 logger.log_exc("sync step failed: %r!"%sync_step)
 255                                                 failed_steps.append(sync_step)
 256
 257                                         if (should_run):
 258                                                 try:
 259                                                         duration=time.time() - start_time
 260
 261                                                         logger.info('Executing step %s' % sync_step.__name__)
 262
 263                                                         # ********* This is the actual sync step
 264                                                         #import pdb
 265                                                         #pdb.set_trace()
 266                                                         failed_objects = sync_step(failed=list(failed_step_objects))
 267
 268
 269                                                         self.check_duration(sync_step, duration)
 270                                                         if failed_objects:
 271                                                                 failed_step_objects.update(failed_objects)
 272                                                         self.update_run_time(sync_step)
 273                                                 except Exception,e:
 274                                                         logging.error('Model step failed. This seems like a misconfiguration or bug: %r',e)
 275                                                         logger.log_exc(e)
 276                                                         failed_steps.append(S)
 277                                 self.save_run_times()
 278                         except Exception, e:
 279                                 logging.error('Core error. This seems like a misconfiguration or bug: %r',e)
 280                                 logger.log_exc("Exception in observer run loop")
 281                                 traceback.print_exc()