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