monitor/database/dbpickle.py

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