monitor/database/dbpickle.py

   1 import os
   2 import sys
   3 import pickle
   4 import inspect
   5 import shutil
   6 import time
   7 from monitor import config
   8
   9 noserial=False
  10 try:
  11         from util.PHPSerialize import *
  12         from util.PHPUnserialize import *
  13 except:
  14         #print >>sys.stderr, "PHPSerial db type not allowed."
  15         noserial=True
  16
  17 DEBUG= 0
  18 PICKLE_PATH=config.MONITOR_DATA_ROOT
  19
  20 def lastModified(name, type=None):
  21         # TODO: fix for 'debug' mode also.
  22         t = SPickle().mtime("production.%s" % name, type)
  23         return t
  24
  25 def cachedRecently(name, length=int(config.cachetime), type=None):
  26         """
  27                 return true or false based on whether the modified time of the cached
  28                 file is within 'length' minutes.
  29         """
  30         if hasattr(config, 'cachecalls') and not config.cachecalls:
  31                 # don't use cached calls if cachecalls is false
  32                 return False
  33
  34         try:
  35                 t = lastModified(name, type)
  36         except:
  37                 # file doesn't exist or we can't access it.
  38                 return False
  39
  40         current_time = time.time()
  41         if current_time > t + length*60:
  42                 return False
  43         else:
  44                 return True
  45
  46 def dbLoad(name, type=None):
  47         return SPickle().load(name, type)
  48
  49 def dbExists(name, type=None):
  50         #if self.config.debug:
  51         #       name = "debug.%s" % name
  52         return SPickle().exists(name, type)
  53
  54 def dbDump(name, obj=None, type=None):
  55         # depth of the dump is 2 now, since we're redirecting to '.dump'
  56         return SPickle().dump(name, obj, type, 2)
  57
  58 def if_cached_else_refresh(cond, refresh, name, function, type=None):
  59         s = SPickle()
  60         if refresh:
  61                 if not config.debug and s.exists("production.%s" % name, type):
  62                         s.remove("production.%s" % name, type)
  63                 if config.debug and s.exists("debug.%s" % name, type):
  64                         s.remove("debug.%s" % name, type)
  65
  66         return if_cached_else(cond, name, function, type)
  67
  68 def if_cached_else(cond, name, function, type=None):
  69         s = SPickle()
  70         if (cond and s.exists("production.%s" % name, type)) or \
  71            (cond and config.debug and s.exists("debug.%s" % name, type)):
  72                 o = s.load(name, type)
  73         else:
  74                 o = function()
  75                 if cond:
  76                         s.dump(name, o, type)   # cache the object using 'name'
  77                         o = s.load(name, type)
  78                 # TODO: what if 'o' hasn't been converted...
  79         return o
  80
  81 class SPickle:
  82         def __init__(self, path=PICKLE_PATH):
  83                 self.path = path
  84
  85         def if_cached_else(self, cond, name, function, type=None):
  86                 if cond and self.exists("production.%s" % name, type):
  87                         o = self.load(name, type)
  88                 else:
  89                         o = function()
  90                         if cond:
  91                                 self.dump(name, o, type)        # cache the object using 'name'
  92                 return o
  93
  94         def __file(self, name, type=None):
  95                 if type == None:
  96                         return "%s/%s.pkl" % (self.path, name)
  97                 else:
  98                         if noserial:
  99                                 raise Exception("No PHPSerializer module available")
 100
 101                         return "%s/%s.phpserial" % (self.path, name)
 102
 103         def mtime(self, name, type=None):
 104                 f = os.stat(self.__file(name, type))
 105                 return f[-2]
 106
 107         def exists(self, name, type=None):
 108                 return os.path.exists(self.__file(name, type))
 109
 110         def remove(self, name, type=None):
 111                 return os.remove(self.__file(name, type))
 112
 113         def load(self, name, type=None):
 114                 """
 115                 In debug mode, we should fail if neither file exists.
 116                         if the debug file exists, reset name
 117                         elif the original file exists, make a copy, reset name
 118                         else neither exist, raise an error
 119                 Otherwise, it's normal mode, if the file doesn't exist, raise error
 120                 Load the file
 121                 """
 122                 #print "loading %s" % name
 123
 124                 if config.debug:
 125                         if self.exists("debug.%s" % name, type):
 126                                 name = "debug.%s" % name
 127                         elif self.exists("production.%s" % name, type):
 128                                 debugname = "debug.%s" % name
 129                                 if not self.exists(debugname, type):
 130                                         name = "production.%s" % name
 131                                         shutil.copyfile(self.__file(name, type), self.__file(debugname, type))
 132                                 name = debugname
 133                         else:   # neither exist
 134                                 raise Exception, "No such pickle based on %s" % self.__file("debug.%s" % name, type)
 135                 else:
 136                         if   self.exists("production.%s" % name, type):
 137                                 name = "production.%s" % name
 138                         elif self.exists(name, type):
 139                                 name = name
 140                         else:
 141                                 raise Exception, "No such file %s" % name
 142
 143
 144                 #import traceback
 145                 #print traceback.print_stack()
 146                 #print "loading %s" % self.__file(name, type)
 147                 #sys.stderr.write("-----------------------------\n")
 148                 f = open(self.__file(name, type), 'r')
 149                 if type == None:
 150                         o = pickle.load(f)
 151                 else:
 152                         if noserial:
 153                                 raise Exception("No PHPSerializer module available")
 154                         s = PHPUnserialize()
 155                         o = s.unserialize(f.read())
 156                 f.close()
 157                 return o
 158
 159
 160         # use the environment to extract the data associated with the local
 161         # variable 'name'
 162         def dump(self, name, obj=None, type=None, depth=1):
 163                 if obj == None:
 164                         o = inspect.getouterframes(inspect.currentframe())
 165                         up1 = o[depth][0] # get the frame one prior to (up from) this frame
 166                         argvals = inspect.getargvalues(up1)
 167                         # TODO: check that 'name' is a local variable; otherwise this would fail.
 168                         obj = argvals[3][name] # extract the local variable name 'name'
 169                 if not os.path.isdir("%s/" % self.path):
 170                         os.mkdir("%s" % self.path)
 171                 if config.debug:
 172                         name = "debug.%s" % name
 173                 else:
 174                         name = "production.%s" % name
 175                 f = open(self.__file(name, type), 'w')
 176                 if type == None:
 177                         pickle.dump(obj, f)
 178                 else:
 179                         if noserial:
 180                                 raise Exception("No PHPSerializer module available")
 181                         s = PHPSerialize()
 182                         f.write(s.serialize(obj))
 183                 f.close()
 184                 return