blob: a539e163b5d549e8a3376c2b18298deae541dc18 [file] [log] [blame]
import os
import base64
from datetime import datetime
from planetstack.config import Config
from util.logger import Logger, logging
from observer.steps import *
from django.db.models import F, Q
logger = Logger(level=logging.INFO)
class FailedDependency(Exception):
pass
class SyncStep:
""" A PlanetStack Sync step.
Attributes:
psmodel Model name the step synchronizes
dependencies list of names of models that must be synchronized first if the current model depends on them
"""
slow=False
def get_prop(prop):
try:
sync_config_dir = Config().sync_config_dir
except:
sync_config_dir = '/etc/planetstack/sync'
prop_config_path = '/'.join(sync_config_dir,self.name,prop)
return open(prop_config_path).read().rstrip()
def __init__(self, **args):
"""Initialize a sync step
Keyword arguments:
name -- Name of the step
provides -- PlanetStack models sync'd by this step
"""
dependencies = []
self.driver = args.get('driver')
self.error_map = args.get('error_map')
try:
self.soft_deadline = int(self.get_prop('soft_deadline_seconds'))
except:
self.soft_deadline = 5 # 5 seconds
return
def fetch_pending(self, deletion=False):
# This is the most common implementation of fetch_pending
# Steps should override it if they have their own logic
# for figuring out what objects are outstanding.
main_obj = self.provides[0]
if (not deletion):
objs = main_obj.objects.filter(Q(enacted__lt=F('updated')) | Q(enacted=None))
else:
objs = main_obj.deleted_objects.all()
return objs
#return Sliver.objects.filter(ip=None)
def check_dependencies(self, obj, failed):
for dep in self.dependencies:
peer_name = dep[0].lower() + dep[1:] # django names are camelCased with the first letter lower
peer_object = getattr(obj, peer_name)
if (peer_object and peer_object.pk==failed.pk and type(peer_object)==type(failed)):
raise FailedDependency("Failed dependency for %s:%s peer %s:%s failed %s:%s" % (obj.__class__.__name__, str(obj.pk\
), peer_object.__class__.__name__, str(peer_object.pk), failed.__class__.__name__, str(failed.pk)))
def call(self, failed=[], deletion=False):
pending = self.fetch_pending(deletion)
for o in pending:
try:
for f in failed:
self.check_dependencies(o,f) # Raises exception if failed
if (deletion):
self.delete_record(o)
o.delete(purge=True)
else:
self.sync_record(o)
o.enacted = datetime.now() # Is this the same timezone? XXX
o.backend_status = "OK"
o.save(update_fields=['enacted'])
except Exception,e:
try:
o.backend_status = self.error_map.map(str(e))
except:
o.backend_status = str(e)
if (o.pk):
o.save(update_fields=['backend_status'])
logger.log_exc("sync step failed!")
failed.append(o)
return failed
def __call__(self, **args):
return self.call(**args)