Robots/bkmk_rforking.py

   1 """Forking robot
   2
   3 This file is a part of Bookmarks database and Internet robot.
   4 """
   5
   6 __version__ = "$Revision$"[11:-2]
   7 __revision__ = "$Id$"[5:-2]
   8 __date__ = "$Date$"[7:-2]
   9 __author__ = "Oleg Broytman <phd@phdru.name>"
  10 __copyright__ = "Copyright (C) 2000-2011 PhiloSoft Design"
  11 __license__ = "GNU GPL"
  12
  13 __all__ = ['robot_forking']
  14
  15
  16 import sys, os
  17
  18 try:
  19    import cPickle as pickle
  20 except ImportError:
  21    import pickle
  22
  23 from subproc import Subprocess, RecordFile
  24 from bkmk_objects import Robot
  25
  26
  27 # This is to catch 'close failed: [Errno 9] Bad file descriptor' message
  28 # from os.close() in Subprocess.die() and errors from from the subprocess.
  29 sys.stderr = open("err.log", 'a')
  30
  31 check_subp = None
  32 subp_pipe = None
  33
  34 def stop_subp(log):
  35    global check_subp, subp_pipe
  36    if check_subp:
  37       if log: log("   restarting hanging subprocess")
  38       del check_subp
  39    del subp_pipe
  40
  41 def restart_subp(log):
  42    global check_subp, subp_pipe
  43    stop_subp(log)
  44
  45    check_subp = Subprocess("%s/Robots/bkmk_rforking_sub.py" % os.path.dirname(sys.argv[0]),
  46       control_stderr=True)
  47    subp_pipe = RecordFile(check_subp)
  48
  49
  50 class robot_forking(Robot):
  51    def check_url(self, bookmark):
  52       if not check_subp:
  53          restart_subp(self.log) # Not restart, just start afresh
  54
  55       try:
  56          save_parent = bookmark.parent
  57          bookmark.parent = None
  58          subp_pipe.write_record(pickle.dumps(bookmark))
  59
  60          if check_subp.waitForPendingChar(60): # wait a minute
  61             new_b = pickle.loads(subp_pipe.read_record())
  62             for attr in ("error", "no_error",
  63                   "moved", "size", "md5", "real_title",
  64                   "last_tested", "last_modified", "test_time",
  65                   "icon", "icon_href"):
  66                if hasattr(new_b, attr):
  67                   setattr(bookmark, attr, getattr(new_b, attr))
  68          else:
  69             bookmark.error = "Subprocess connection timed out"
  70             restart_subp(self.log)
  71
  72          bookmark.parent = save_parent
  73
  74          while True:
  75             error = check_subp.readPendingErrLine()
  76             if not error:
  77                break
  78             sys.stderr.write("(subp) " + error)
  79          sys.stderr.flush()
  80
  81       except KeyboardInterrupt:
  82          return 0
  83
  84       # Tested
  85       return 1
  86
  87    def stop(self):
  88       stop_subp(None) # Stop subprocess; do not log restarting