pcucontrol/util/command.py

   1 import os
   2 from select import select
   3 import subprocess
   4 import signal
   5 import time
   6 import traceback
   7 import fcntl
   8
   9 DEBUG= 0
  10
  11 class ExceptionTimeout(Exception): pass
  12 class ExceptionReadTimeout(Exception): pass
  13 COMMAND_TIMEOUT = 60
  14 ssh_options = { 'StrictHostKeyChecking':'no',
  15                                 'BatchMode':'yes',
  16                                 'PasswordAuthentication':'no',
  17                                 'ConnectTimeout':'%s' % COMMAND_TIMEOUT}
  18
  19 class Sopen(subprocess.Popen):
  20         def kill(self, sig = signal.SIGTERM):
  21                 try:
  22                         # NOTE: this also kills parent... so doesn't work like I want.
  23                         # NOTE: adding 'exec' before the cmd removes the extra sh, and
  24                         #               partially addresses this problem.
  25                         #os.killpg(os.getpgid(self.pid), signal.SIGKILL)
  26                         os.kill(self.pid, sig)
  27                 except OSError:
  28                         # no such process, due to it already exiting...
  29                         pass
  30
  31
  32 def read_t(stream, count=1, timeout=COMMAND_TIMEOUT*2):
  33         if count == 1:
  34                 retstr = ""
  35
  36                 while True:
  37                         lin, lout, lerr = select([stream], [], [], timeout)
  38                         if len(lin) == 0:
  39                                 #print "timeout!"
  40                                 raise ExceptionReadTimeout("TIMEOUT while reading from command")
  41
  42                         try:
  43                                 outbytes = stream.read(count)
  44                         except IOError, err:
  45                                 print 'no content yet.'
  46                                 # due to no content.
  47                                 # the select timeout should catch this.
  48                                 continue
  49
  50                         if not outbytes:
  51                                 break
  52                         retstr += outbytes
  53
  54                 return retstr
  55         else:
  56                 lin, lout, lerr = select([stream], [], [], timeout)
  57                 if len(lin) == 0:
  58                         raise ExceptionReadTimeout("TIMEOUT while reading from command")
  59
  60                 return stream.read(count)
  61
  62 class CMD:
  63         def __init__(self):
  64                 pass
  65
  66         def run_noexcept(self, cmd, timeout=COMMAND_TIMEOUT*2):
  67
  68                 try:
  69                         return CMD.run(self,cmd,timeout)
  70                 except ExceptionTimeout:
  71                         #print traceback.print_exc()
  72                         return ("", "ScriptTimeout")
  73                 except ExceptionReadTimeout:
  74                         #print traceback.print_exc()
  75                         return ("", "RunningScriptTimeout")
  76                 except KeyboardInterrupt:
  77                         print "Interrupted, exiting..."
  78                         sys.exit(1)
  79                 except Exception, err:
  80                         #from monitor.common import email_exception
  81                         #email_exception()
  82                         return ("", str(err))
  83
  84         def system(self, cmd, timeout=COMMAND_TIMEOUT*2):
  85                 (o,e) = self.run(cmd, timeout)
  86                 self.output = o
  87                 self.error = e
  88                 if self.s.returncode is None:
  89                         self.s.wait()
  90                 return self.s.returncode
  91
  92         def run(self, cmd, timeout=COMMAND_TIMEOUT*2):
  93
  94                 s = Sopen(cmd, shell=True,
  95                     stdin=subprocess.PIPE,
  96                     stdout=subprocess.PIPE,
  97                     stderr=subprocess.PIPE,
  98                     close_fds=True)
  99                 self.s = s
 100                 (f_in, f_out, f_err) = (s.stdin, s.stdout, s.stderr)
 101                 lout, lin, lerr = select([f_out], [], [f_err], timeout)
 102                 if len(lin) == 0 and len(lout) == 0 and len(lerr) == 0:
 103                         # Reached a timeout!  Nuke process so it does not hang.
 104                         #print "TIMEOUT!!!!!!!!!!!!!!!!!!!"
 105                         s.kill(signal.SIGKILL)
 106                         raise ExceptionTimeout("TIMEOUT Running: %s" % cmd)
 107                 else:
 108                         #print "RETURNING"
 109                         #print len(lin), len(lout), len(lerr)
 110                         pass
 111
 112                 o_value = ""
 113                 e_value = ""
 114
 115                 #o_value = f_out.read()
 116                 flags = fcntl.fcntl(f_out, fcntl.F_GETFL)
 117                 fcntl.fcntl(f_out, fcntl.F_SETFL, flags | os.O_NONBLOCK)
 118
 119                 try:
 120                         o_value = read_t(f_out,1,30)
 121                 except ExceptionReadTimeout:
 122                         s.kill(signal.SIGKILL)
 123                         raise ExceptionReadTimeout("TIMEOUT: failed to read from cmd: %s" % cmd)
 124
 125                 e_value = f_err.read()
 126
 127                 o_value = o_value.strip()
 128                 e_value = e_value.strip()
 129
 130                 f_out.close()
 131                 f_in.close()
 132                 f_err.close()
 133                 s.poll()
 134                 s.kill(signal.SIGKILL)
 135
 136                 return (o_value, e_value)
 137
 138         def runargs(self, args, timeout=COMMAND_TIMEOUT*2):
 139
 140                 #print "CMD.run(%s)" % " ".join(args)
 141                 s = Sopen(args, shell=True, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, close_fds=True)
 142                 self.s = s
 143                 (f_in, f_out, f_err) = (s.stdin, s.stdout, s.stderr)
 144                 lout, lin, lerr = select([f_out], [], [f_err], timeout)
 145                 if len(lin) == 0 and len(lout) == 0 and len(lerr) == 0:
 146                         # Reached a timeout!  Nuke process so it does not hang.
 147                         s.kill(signal.SIGKILL)
 148                         raise ExceptionTimeout("TIMEOUT Running: %s" % cmd)
 149                 o_value = f_out.read()
 150                 e_value = ""
 151                 if o_value == "":       # An error has occured
 152                         e_value = f_err.read()
 153
 154                 o_value = o_value.strip()
 155                 e_value = e_value.strip()
 156
 157                 f_out.close()
 158                 f_in.close()
 159                 f_err.close()
 160                 s.kill(signal.SIGKILL)
 161
 162                 return (o_value, e_value)
 163
 164
 165 class SSH(CMD):
 166         def __init__(self, user, host, port=22, options = ssh_options):
 167                 self.options = options
 168                 self.user = user
 169                 self.host = host
 170                 self.port = port
 171                 return
 172
 173         def __options_to_str(self):
 174                 options = ""
 175                 for o,v in self.options.iteritems():
 176                         options = options + "-o %s=%s " % (o,v)
 177                 return options
 178
 179         def run(self, cmd, timeout=COMMAND_TIMEOUT*2):
 180                 cmd = "ssh -p %s %s %s@%s '%s'" % (self.port, self.__options_to_str(),
 181                                                                         self.user, self.host, cmd)
 182                 #print "SSH.run(%s)" % cmd
 183                 return CMD.run(self, cmd, timeout)
 184
 185         def get_file(self, rmt_filename, local_filename=None):
 186                 if local_filename == None:
 187                         local_filename = "./"
 188                 cmd = "scp -P %s -B %s %s@%s:%s %s" % (self.port, self.__options_to_str(),
 189                                                                         self.user, self.host,
 190                                                                         rmt_filename, local_filename)
 191                 # output :
 192                 #       errors will be on stderr,
 193                 #   success will have a blank stderr...
 194                 return CMD.run_noexcept(self, cmd)
 195
 196         def run_noexcept(self, cmd):
 197                 cmd = "ssh -p %s %s %s@%s '%s'" % (self.port, self.__options_to_str(),
 198                                                                         self.user, self.host, cmd)
 199                 #print "SSH.run_noexcept(%s)" % cmd
 200                 return CMD.run_noexcept(self, cmd)
 201
 202         def run_noexcept2(self, cmd, timeout=COMMAND_TIMEOUT*2):
 203                 cmd = "exec ssh -p %s %s %s@%s %s" % (self.port, self.__options_to_str(),
 204                                                                         self.user, self.host, cmd)
 205                 #print cmd
 206                 r = CMD.run_noexcept(self, cmd, timeout)
 207                 self.ret = -1
 208
 209                 return r
 210
 211         def system2(self, cmd, timeout=COMMAND_TIMEOUT*2):
 212                 cmd = "ssh -p %s %s %s@%s %s" % (self.port, self.__options_to_str(),
 213                                                                         self.user, self.host, cmd)
 214                 #print "SSH.system2(%s)" % cmd
 215                 return CMD.system(self, cmd, timeout)
 216
 217         def runE(self, cmd):
 218                 cmd = "ssh -p %s %s %s@%s '%s'" % (self.port, self.__options_to_str(),
 219                                                                         self.user, self.host, cmd)
 220                 if ( DEBUG == 1 ):
 221                         print cmd,
 222                 (f_in, f_out, f_err) = os.popen3(cmd)
 223
 224                 value = f_out.read()
 225                 if value == "": # An error has occured
 226                         value = f_err.read()
 227                         value = value.strip()
 228
 229                 if ( DEBUG == 1 ):
 230                         print " == %s" % value
 231                 f_out.close()
 232                 f_in.close()
 233                 f_err.close()
 234                 return value.strip()
 235
 236 class MyTimer:
 237         def __init__(self):
 238                 self.start = time.time()
 239
 240         def end(self):
 241                 self.end = time.time()
 242                 t = self.end-self.start
 243                 return t
 244
 245         def diff(self):
 246                 self.end = time.time()
 247                 t = self.end-self.start
 248                 self.start = self.end
 249                 return t