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