pykickstart/version.py

   1 #
   2 # Chris Lumens <clumens@redhat.com>
   3 #
   4 # Copyright 2006, 2007 Red Hat, Inc.
   5 #
   6 # This software may be freely redistributed under the terms of the GNU
   7 # general public license.
   8 #
   9 # You should have received a copy of the GNU General Public License
  10 # along with this program; if not, write to the Free Software
  11 # Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  12 #
  13 """
  14 Methods for working with kickstart versions.
  15
  16 This module defines several symbolic constants that specify kickstart syntax
  17 versions.  Each version corresponds roughly to one release of Red Hat Linux,
  18 Red Hat Enterprise Linux, or Fedora Core as these are where most syntax
  19 changes take place.
  20
  21 This module also exports several functions:
  22
  23     makeVersion - Given a version number, return an instance of the
  24                   matching handler class.
  25
  26     returnClassForVersion - Given a version number, return the matching
  27                             handler class.  This does not return an
  28                             instance of that class, however.
  29
  30     stringToVersion - Convert a string representation of a version number
  31                       into the symbolic constant.
  32
  33     versionToString - Perform the reverse mapping.
  34 """
  35 import re
  36
  37 from rhpl.translate import _
  38 from pykickstart.errors import KickstartVersionError
  39
  40 # Symbolic names for internal version numbers.
  41 RHEL3 = 900
  42 FC3 = 1000
  43 RHEL4 = 1100
  44 FC4 = 2000
  45 FC5 = 3000
  46 FC6 = 4000
  47 RHEL5 = 4100
  48 F7  = 5000
  49 F8 = 6000
  50
  51 # This always points at the latest version and is the default.
  52 DEVEL = F8
  53
  54 """A one-to-one mapping from string representations to version numbers."""
  55 versionMap = {
  56         "DEVEL": DEVEL,
  57         "FC3": FC3, "FC4": FC4, "FC5": FC5, "FC6": FC6, "F7": F7, "F8": F8,
  58         "RHEL3": RHEL3, "RHEL4": RHEL4, "RHEL5": RHEL5
  59 }
  60
  61 def stringToVersion(string):
  62     """Convert string into one of the provided version constants.  Raises
  63        KickstartVersionError if string does not match anything.
  64     """
  65     # First try these short forms.
  66     try:
  67         return versionMap[string.upper()]
  68     except KeyError:
  69         pass
  70
  71     # Now try the Fedora versions.
  72     m = re.match("^fedora.* (\d)+$", string, re.I)
  73
  74     if m and m.group(1):
  75         if versionMap.has_key("FC" + m.group(1)):
  76             return versionMap["FC" + m.group(1)]
  77         elif versionMap.has_key("F" + m.group(1)):
  78             return versionMap["F" + m.group(1)]
  79         else:
  80             raise KickstartVersionError(_("Unsupported version specified: %s") % string)
  81
  82     # Now try the RHEL versions.
  83     m = re.match("^red hat enterprise linux.* (\d)+$", string, re.I)
  84
  85     if m and m.group(1):
  86         if versionMap.has_key("RHEL" + m.group(1)):
  87             return versionMap["RHEL" + m.group(1)]
  88         else:
  89             raise KickstartVersionError(_("Unsupported version specified: %s") % string)
  90
  91     # If nothing else worked, we're out of options.
  92     raise KickstartVersionError(_("Unsupported version specified: %s") % string)
  93
  94 def versionToString(version):
  95     """Convert version into a string representation of the version number.
  96        This is the reverse operation of stringToVersion.  Raises
  97        KickstartVersionError if version does not match anything.
  98     """
  99     for (key, val) in versionMap.iteritems():
 100         if val == version:
 101             return key
 102
 103     raise KickstartVersionError(_("Unsupported version specified: %s") % version)
 104
 105 def returnClassForVersion(version=DEVEL):
 106     """Return the class of the syntax handler for version.  version can be
 107        either a string or the matching constant.  Raises KickstartValueError
 108        if version does not match anything.
 109     """
 110     try:
 111         version = int(version)
 112     except ValueError:
 113         version = stringToVersion(version)
 114
 115     if version == FC3:
 116         from pykickstart.handlers.fc3 import FC3Handler
 117         return FC3Handler
 118     elif version == FC4:
 119         from pykickstart.handlers.fc4 import FC4Handler
 120         return FC4Handler
 121     elif version == FC5:
 122         from pykickstart.handlers.fc5 import FC5Handler
 123         return FC5Handler
 124     elif version == FC6:
 125         from pykickstart.handlers.fc6 import FC6Handler
 126         return FC6Handler
 127     elif version == F7:
 128         from pykickstart.handlers.f7 import F7Handler
 129         return F7Handler
 130     elif version == F8:
 131         from pykickstart.handlers.f8 import F8Handler
 132         return F8Handler
 133     elif version == RHEL3:
 134         from pykickstart.handlers.rhel3 import RHEL3Handler
 135         return RHEL3Handler
 136     elif version == RHEL4:
 137         from pykickstart.handlers.rhel4 import RHEL4Handler
 138         return RHEL4Handler
 139     elif version == RHEL5:
 140         from pykickstart.handlers.rhel5 import RHEL5Handler
 141         return RHEL5Handler
 142     else:
 143         raise KickstartVersionError(_("Unsupported version specified: %s") % version)
 144
 145 def makeVersion(version=DEVEL):
 146     """Return a new instance of the syntax handler for version.  version can be
 147        either a string or the matching constant.  This function is useful for
 148        standalone programs which just need to handle a specific version of
 149        kickstart syntax (as provided by a command line argument, for example)
 150        and need to instantiate the correct object.
 151     """
 152     cl = returnClassForVersion(version)
 153     return cl()