wizard/util.py

   1 import os.path
   2 import os
   3 import subprocess
   4 import pwd
   5 import sys
   6
   7 import wizard
   8
   9 class ChangeDirectory(object):
  10     """Context for temporarily changing directory"""
  11     def __init__(self, dir):
  12         self.dir = dir
  13         self.olddir = None
  14     def __enter__(self):
  15         self.olddir = os.getcwd()
  16         os.chdir(self.dir)
  17     def __exit__(self, *args):
  18         os.chdir(self.olddir)
  19
  20 def get_exception_name(output):
  21     """Reads the stderr output of another Python command and grabs the
  22     fully qualified exception name"""
  23     lines = output.split("\n")
  24     for line in lines[1:]: # skip the "traceback" line
  25         line = line.rstrip()
  26         if line[0] == ' ': continue
  27         if line[-1] == ":":
  28             return line[:-1]
  29         else:
  30             return line
  31
  32 def get_dir_uid(dir):
  33     """Finds the uid of the person who owns this directory."""
  34     return os.stat(dir).st_uid
  35
  36 def get_dir_owner(dir = "."):
  37     """Finds the name of the locker this directory is in."""
  38     return pwd.getpwuid(get_dir_uid(dir)).pw_name
  39
  40 def get_revision():
  41     """Returns the commit ID of the current Wizard install."""
  42     wizard_git = os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))), ".git")
  43     return subprocess.Popen(["git", "--git-dir=" + wizard_git, "rev-parse", "HEAD"], stdout=subprocess.PIPE).communicate()[0].rstrip()
  44
  45 def get_operator_info():
  46     """Returns tuple of (realname, email) of person who is operating
  47     this script, as told to use by the Kerberos principal name.
  48     Useful for commit messages."""
  49     username = get_operator_name()
  50     hesinfo = subprocess.Popen(["hesinfo", username, "passwd"],stdout=subprocess.PIPE).communicate()[0]
  51     fields = hesinfo.partition(",")[0]
  52     realname = fields.rpartition(":")[2]
  53     return realname, username + "@mit.edu"
  54
  55 def get_operator_git():
  56     """Returns Real Name <username@mit.edu> suitable for use in
  57     Git Something-by: string."""
  58     return "%s <%s>" % get_operator_info()
  59
  60 def get_operator_name():
  61     """Returns username of the person operating this script."""
  62     principal = os.getenv("SSH_GSSAPI_NAME")
  63     if not principal: raise NoOperatorInfo()
  64     instance, _, _ = principal.partition("@")
  65     if instance.endswith("/root"):
  66         username, _, _ = principal.partition("/")
  67     else:
  68         username = instance
  69     return username
  70
  71 def set_operator_env():
  72     try:
  73         op_realname, op_email = get_operator_info()
  74         os.putenv("GIT_COMMITTER_NAME", op_realname)
  75         os.putenv("GIT_COMMITTER_EMAIL", op_email)
  76     except NoOperatorInfo:
  77         pass
  78
  79 def set_author_env():
  80     try:
  81         lockername = get_dir_owner()
  82         os.putenv("GIT_AUTHOR_NAME", "%s locker" % lockername)
  83         os.putenv("GIT_AUTHOR_EMAIL", "%s@scripts.mit.edu" % lockername)
  84     except KeyError:
  85         pass
  86
  87 def set_git_env():
  88     set_operator_env()
  89     set_author_env()
  90
  91 def get_git_footer():
  92     return "\n".join(["Wizard-revision: %s" % get_revision()
  93         ,"Wizard-args: %s" % " ".join(sys.argv)
  94         ])
  95
  96 class Error(wizard.Error):
  97     pass
  98
  99 class NoOperatorInfo(Error):
 100     pass
 101