monitor/database/pickle.py

   1 import os
   2 import sys
   3 import pickle
   4 noserial=False
   5 try:
   6         from util.PHPSerialize import *
   7         from util.PHPUnserialize import *
   8 except:
   9         #print >>sys.stderr, "PHPSerial db type not allowed."
  10         noserial=True
  11
  12 import inspect
  13 import shutil
  14 import config
  15 import config as monitorconfig
  16
  17 DEBUG= 0
  18 PICKLE_PATH=config.MONITOR_DATA_ROOT
  19
  20
  21 def dbLoad(name, type=None):
  22         return SPickle().load(name, type)
  23
  24 def dbExists(name, type=None):
  25         #if self.config.debug:
  26         #       name = "debug.%s" % name
  27         return SPickle().exists(name, type)
  28
  29 def dbDump(name, obj=None, type=None):
  30         # depth of the dump is 2 now, since we're redirecting to '.dump'
  31         return SPickle().dump(name, obj, type, 2)
  32
  33 def if_cached_else_refresh(cond, refresh, name, function, type=None):
  34         s = SPickle()
  35         if refresh:
  36                 if not config.debug and s.exists("production.%s" % name, type):
  37                         s.remove("production.%s" % name, type)
  38                 if config.debug and s.exists("debug.%s" % name, type):
  39                         s.remove("debug.%s" % name, type)
  40
  41         return if_cached_else(cond, name, function, type)
  42
  43 def if_cached_else(cond, name, function, type=None):
  44         s = SPickle()
  45         if (cond and s.exists("production.%s" % name, type)) or \
  46            (cond and config.debug and s.exists("debug.%s" % name, type)):
  47                 o = s.load(name, type)
  48         else:
  49                 o = function()
  50                 if cond:
  51                         s.dump(name, o, type)   # cache the object using 'name'
  52                         o = s.load(name, type)
  53                 # TODO: what if 'o' hasn't been converted...
  54         return o
  55
  56 class SPickle:
  57         def __init__(self, path=PICKLE_PATH):
  58                 self.path = path
  59
  60         def if_cached_else(self, cond, name, function, type=None):
  61                 if cond and self.exists("production.%s" % name, type):
  62                         o = self.load(name, type)
  63                 else:
  64                         o = function()
  65                         if cond:
  66                                 self.dump(name, o, type)        # cache the object using 'name'
  67                 return o
  68
  69         def __file(self, name, type=None):
  70                 if type == None:
  71                         return "%s/%s.pkl" % (self.path, name)
  72                 else:
  73                         if noserial:
  74                                 raise Exception("No PHPSerializer module available")
  75
  76                         return "%s/%s.phpserial" % (self.path, name)
  77
  78         def exists(self, name, type=None):
  79                 return os.path.exists(self.__file(name, type))
  80
  81         def remove(self, name, type=None):
  82                 return os.remove(self.__file(name, type))
  83
  84         def load(self, name, type=None):
  85                 """
  86                 In debug mode, we should fail if neither file exists.
  87                         if the debug file exists, reset name
  88                         elif the original file exists, make a copy, reset name
  89                         else neither exist, raise an error
  90                 Otherwise, it's normal mode, if the file doesn't exist, raise error
  91                 Load the file
  92                 """
  93                 print "loading %s" % name
  94
  95                 if config.debug:
  96                         if self.exists("debug.%s" % name, type):
  97                                 name = "debug.%s" % name
  98                         elif self.exists("production.%s" % name, type):
  99                                 debugname = "debug.%s" % name
 100                                 if not self.exists(debugname, type):
 101                                         name = "production.%s" % name
 102                                         shutil.copyfile(self.__file(name, type), self.__file(debugname, type))
 103                                 name = debugname
 104                         else:   # neither exist
 105                                 raise Exception, "No such pickle based on %s" % self.__file("debug.%s" % name, type)
 106                 else:
 107                         if   self.exists("production.%s" % name, type):
 108                                 name = "production.%s" % name
 109                         elif self.exists(name, type):
 110                                 name = name
 111                         else:
 112                                 raise Exception, "No such file %s" % name
 113
 114
 115                 #import traceback
 116                 #print traceback.print_stack()
 117                 #print "loading %s" % self.__file(name, type)
 118                 #sys.stderr.write("-----------------------------\n")
 119                 f = open(self.__file(name, type), 'r')
 120                 if type == None:
 121                         o = pickle.load(f)
 122                 else:
 123                         if noserial:
 124                                 raise Exception("No PHPSerializer module available")
 125                         s = PHPUnserialize()
 126                         o = s.unserialize(f.read())
 127                 f.close()
 128                 return o
 129
 130
 131         # use the environment to extract the data associated with the local
 132         # variable 'name'
 133         def dump(self, name, obj=None, type=None, depth=1):
 134                 if obj == None:
 135                         o = inspect.getouterframes(inspect.currentframe())
 136                         up1 = o[depth][0] # get the frame one prior to (up from) this frame
 137                         argvals = inspect.getargvalues(up1)
 138                         # TODO: check that 'name' is a local variable; otherwise this would fail.
 139                         obj = argvals[3][name] # extract the local variable name 'name'
 140                 if not os.path.isdir("%s/" % self.path):
 141                         os.mkdir("%s" % self.path)
 142                 if config.debug:
 143                         name = "debug.%s" % name
 144                 else:
 145                         name = "production.%s" % name
 146                 f = open(self.__file(name, type), 'w')
 147                 if type == None:
 148                         pickle.dump(obj, f)
 149                 else:
 150                         if noserial:
 151                                 raise Exception("No PHPSerializer module available")
 152                         s = PHPSerialize()
 153                         f.write(s.serialize(obj))
 154                 f.close()
 155                 return