output.py

   1 #!/usr/bin/env python
   2
   3 import os
   4 import shutil
   5 import sys
   6 import time
   7
   8 from conf import config
   9
  10
  11 class Logger:
  12
  13         def __init__(self):
  14                 self.dirty = False
  15                 self.pending = None
  16                 self.muted = False
  17
  18         # output: => Requesting ip...
  19         def await(self, msg):
  20                 if self.pending:
  21                         raise Exception,\
  22                         "Attempted to display new pending message without closing previous"
  23
  24                 msg = "=> %s..." % msg
  25                 self.pending = msg
  26                 self.dirty = False
  27                 print msg,
  28                 sys.stdout.flush()
  29                 self.log(msg)
  30
  31         # output: (=> Requesting ip...) done
  32         def result(self, msg):
  33                 if not self.pending:
  34                         raise Exception,\
  35                         "Attempted to display result of action without pending message"
  36
  37                 if not self.dirty:
  38                         print msg
  39                         self.log("%s %s" % (self.pending, msg))
  40                 else:
  41                         msg = "%s %s" % (self.pending, msg)
  42                         print "\r%s" % msg  # workaround for space at the start of the line
  43                         self.log(msg)
  44                 self.pending = None
  45
  46         def display(self, msg):
  47                 if self.pending and not self.dirty:
  48                         self.dirty = True
  49                         msg = "\n%s" % msg
  50                 print msg
  51                 self.log(msg)
  52
  53         def err(self, msg, log=True):
  54                 msg = "Erratum: %s" % msg
  55                 if self.pending:
  56                         self.dirty = True
  57                         print >>sys.stderr, "\n%s" % msg
  58                 else: print >>sys.stderr, msg
  59                 if log: self.log(msg)
  60
  61         def log(self, msg):
  62                 if self.muted: return
  63                 try:
  64                         # truncate logfile
  65                         if os.path.isfile(config.logfile) and \
  66                                 os.path.getsize(config.logfile) > config.logfile_size:
  67                                 shutil.move(config.logfile, "%s.0" % config.logfile)
  68
  69                         t = time.strftime("%d.%m.%y %H:%M:%S", time.gmtime())
  70
  71                         f = open(config.logfile, 'a')
  72                         if msg[-1:] != '\n': msg += '\n'
  73                         f.write("[%s] %s" % (t, msg))
  74                         f.close()
  75                 except IOError:
  76                         self.err("Could not write to logfile %s" % config.logfile, log=False)
  77
  78         def mute(self, quiet=False):
  79                 if self.muted: return
  80                 if not quiet:
  81                         self.display("*** Halting output until we need to obtain ip again")
  82                 sys.stdin  = open("/dev/null", 'r')
  83                 sys.stdout = open("/dev/null", 'w')
  84                 sys.stderr = open("/dev/null", 'w')
  85                 self.muted = True
  86
  87         def unmute(self, quiet=False):
  88                 if not self.muted: return
  89                 sys.stdin  = sys.__stdin__
  90                 sys.stdout = sys.__stdout__
  91                 sys.stderr = sys.__stderr__
  92                 if not quiet: self.display("*** Resuming output")
  93                 self.muted = False
  94
  95
  96 logger = Logger()