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 escapeName(name):
  26         """
  27                 automatically escape names passed to the db to make sensible-filenames without
  28                 exposing this to users.
  29         """
  30         return name.replace("/", "_")
  31
  32 def cachedRecently(name, length=int(config.cachetime), type=None):
  33         """
  34                 return true or false based on whether the modified time of the cached
  35                 file is within 'length' minutes.
  36         """
  37         name = name.replace("/", "_")
  38         if hasattr(config, 'cachecalls') and not config.cachecalls:
  39                 # don't use cached calls if cachecalls is false
  40                 return False
  41
  42         try:
  43                 t = lastModified(name, type)
  44         except:
  45                 # file doesn't exist or we can't access it.
  46                 return False
  47
  48         current_time = time.time()
  49         if current_time > t + length*60:
  50                 return False
  51         else:
  52                 return True
  53
  54 def dbLoad(name, type=None):
  55         name = escapeName(name)
  56         return SPickle().load(name, type)
  57
  58 def dbExists(name, type=None):
  59         name = escapeName(name)
  60         return SPickle().exists(name, type)
  61
  62 def dbDump(name, obj=None, type=None):
  63         name = escapeName(name)
  64         # depth of the dump is 2 now, since we're redirecting to '.dump'
  65         return SPickle().dump(name, obj, type, 2)
  66
  67 def if_cached_else_refresh(cond, refresh, name, function, type=None):
  68         s = SPickle()
  69         if refresh:
  70                 if not config.debug and s.exists("production.%s" % name, type):
  71                         s.remove("production.%s" % name, type)
  72                 if config.debug and s.exists("debug.%s" % name, type):
  73                         s.remove("debug.%s" % name, type)
  74
  75         return if_cached_else(cond, name, function, type)
  76
  77 def if_cached_else(cond, name, function, type=None):
  78         s = SPickle()
  79         if (cond and s.exists("production.%s" % name, type)) or \
  80            (cond and config.debug and s.exists("debug.%s" % name, type)):
  81                 o = s.load(name, type)
  82         else:
  83                 o = function()
  84                 if cond:
  85                         s.dump(name, o, type)   # cache the object using 'name'
  86                         o = s.load(name, type)
  87                 # TODO: what if 'o' hasn't been converted...
  88         return o
  89
  90 class SPickle:
  91         def __init__(self, path=PICKLE_PATH):
  92                 self.path = path
  93
  94         def if_cached_else(self, cond, name, function, type=None):
  95                 if cond and self.exists("production.%s" % name, type):
  96                         o = self.load(name, type)
  97                 else:
  98                         o = function()
  99                         if cond:
 100                                 self.dump(name, o, type)        # cache the object using 'name'
 101                 return o
 102
 103         def __file(self, name, type=None):
 104                 if type == None:
 105                         return "%s/%s.pkl" % (self.path, name)
 106                 else:
 107                         if noserial:
 108                                 raise Exception("No PHPSerializer module available")
 109
 110                         return "%s/%s.phpserial" % (self.path, name)
 111
 112         def mtime(self, name, type=None):
 113                 f = os.stat(self.__file(name, type))
 114                 return f[-2]
 115
 116         def exists(self, name, type=None):
 117                 return os.path.exists(self.__file(name, type))
 118
 119         def remove(self, name, type=None):
 120                 return os.remove(self.__file(name, type))
 121
 122         def load(self, name, type=None):
 123                 """
 124                 In debug mode, we should fail if neither file exists.
 125                         if the debug file exists, reset name
 126                         elif the original file exists, make a copy, reset name
 127                         else neither exist, raise an error
 128                 Otherwise, it's normal mode, if the file doesn't exist, raise error
 129                 Load the file
 130                 """
 131                 #print "loading %s" % name
 132
 133                 if config.debug:
 134                         if self.exists("debug.%s" % name, type):
 135                                 name = "debug.%s" % name
 136                         elif self.exists("production.%s" % name, type):
 137                                 debugname = "debug.%s" % name
 138                                 if not self.exists(debugname, type):
 139                                         name = "production.%s" % name
 140                                         shutil.copyfile(self.__file(name, type), self.__file(debugname, type))
 141                                 name = debugname
 142                         else:   # neither exist
 143                                 raise Exception, "No such pickle based on %s" % self.__file("debug.%s" % name, type)
 144                 else:
 145                         if   self.exists("production.%s" % name, type):
 146                                 name = "production.%s" % name
 147                         elif self.exists(name, type):
 148                                 name = name
 149                         else:
 150                                 raise Exception, "No such file %s" % name
 151
 152
 153                 #import traceback
 154                 #print traceback.print_stack()
 155                 #print "loading %s" % self.__file(name, type)
 156                 #sys.stderr.write("-----------------------------\n")
 157                 f = open(self.__file(name, type), 'r')
 158                 if type == None:
 159                         o = pickle.load(f)
 160                 else:
 161                         if noserial:
 162                                 raise Exception("No PHPSerializer module available")
 163                         s = PHPUnserialize()
 164                         o = s.unserialize(f.read())
 165                 f.close()
 166                 return o
 167
 168
 169         # use the environment to extract the data associated with the local
 170         # variable 'name'
 171         def dump(self, name, obj=None, type=None, depth=1):
 172                 if obj == None:
 173                         o = inspect.getouterframes(inspect.currentframe())
 174                         up1 = o[depth][0] # get the frame one prior to (up from) this frame
 175                         argvals = inspect.getargvalues(up1)
 176                         # TODO: check that 'name' is a local variable; otherwise this would fail.
 177                         obj = argvals[3][name] # extract the local variable name 'name'
 178                 if not os.path.isdir("%s/" % self.path):
 179                         os.mkdir("%s" % self.path)
 180                 if config.debug:
 181                         name = "debug.%s" % name
 182                 else:
 183                         name = "production.%s" % name
 184                 f = open(self.__file(name, type), 'w')
 185                 if type == None:
 186                         pickle.dump(obj, f)
 187                 else:
 188                         if noserial:
 189                                 raise Exception("No PHPSerializer module available")
 190                         s = PHPSerialize()
 191                         f.write(s.serialize(obj))
 192                 f.close()
 193                 return