import os import base64 from datetime import datetime from planetstack.config import Config from util.logger import Logger, logging from observer.steps import * 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 deleted): 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.pk==failed.pk): raise FailedDependency 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) 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)