pykickstart/version.py

   1 #
   2 # Chris Lumens <clumens@redhat.com>
   3 #
   4 # Copyright 2006-2014 Red Hat, Inc.
   5 #
   6 # This copyrighted material is made available to anyone wishing to use, modify,
   7 # copy, or redistribute it subject to the terms and conditions of the GNU
   8 # General Public License v.2.  This program is distributed in the hope that it
   9 # will be useful, but WITHOUT ANY WARRANTY expressed or implied, including the
  10 # implied warranties of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  11 # See the GNU General Public License for more details.
  12 #
  13 # You should have received a copy of the GNU General Public License along with
  14 # this program; if not, write to the Free Software Foundation, Inc., 51
  15 # Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  Any Red Hat
  16 # trademarks that are incorporated in the source code or documentation are not
  17 # subject to the GNU General Public License and may only be used or replicated
  18 # with the express permission of Red Hat, Inc.
  19 #
  20 """
  21 Methods for working with kickstart versions.
  22
  23 This module defines several symbolic constants that specify kickstart syntax
  24 versions.  Each version corresponds roughly to one release of Red Hat Linux,
  25 Red Hat Enterprise Linux, or Fedora Core as these are where most syntax
  26 changes take place.
  27
  28 This module also exports several functions:
  29
  30     makeVersion - Given a version number, return an instance of the
  31                   matching handler class.
  32
  33     returnClassForVersion - Given a version number, return the matching
  34                             handler class.  This does not return an
  35                             instance of that class, however.
  36
  37     stringToVersion - Convert a string representation of a version number
  38                       into the symbolic constant.
  39
  40     versionToString - Perform the reverse mapping.
  41
  42     versionFromFile - Read a kickstart file and determine the version of
  43                       syntax it uses.  This requires the kickstart file to
  44                       have a version= comment in it.
  45 """
  46 import imputil, re, sys
  47 from urlgrabber import urlopen
  48
  49 import gettext
  50 _ = lambda x: gettext.ldgettext("pykickstart", x)
  51
  52 from pykickstart.errors import KickstartVersionError
  53
  54 # Symbolic names for internal version numbers.
  55 RHEL3 = 900
  56 FC3 = 1000
  57 RHEL4 = 1100
  58 FC4 = 2000
  59 FC5 = 3000
  60 FC6 = 4000
  61 RHEL5 = 4100
  62 F7  = 5000
  63 F8 = 6000
  64 F9 = 7000
  65 F10 = 8000
  66 F11 = 9000
  67 F12 = 10000
  68 F13 = 11000
  69 RHEL6 = 11100
  70 F14 = 12000
  71 F15 = 13000
  72 F16 = 14000
  73 F17 = 15000
  74 F18 = 16000
  75 F19 = 17000
  76 RHEL7 = 17100
  77 F20 = 18000
  78 F21 = 19000
  79 F22 = 20000
  80
  81 # This always points at the latest version and is the default.
  82 DEVEL = F22
  83
  84 # A one-to-one mapping from string representations to version numbers.
  85 versionMap = {
  86         "DEVEL": DEVEL,
  87         "FC3": FC3, "FC4": FC4, "FC5": FC5, "FC6": FC6, "F7": F7, "F8": F8,
  88         "F9": F9, "F10": F10, "F11": F11, "F12": F12, "F13": F13,
  89         "F14": F14, "F15": F15, "F16": F16, "F17": F17, "F18": F18,
  90         "F19": F19, "F20": F20, "F21": F21, "F22": F22,
  91         "RHEL3": RHEL3, "RHEL4": RHEL4, "RHEL5": RHEL5, "RHEL6": RHEL6,
  92         "RHEL7": RHEL7
  93 }
  94
  95 def stringToVersion(s):
  96     """Convert string into one of the provided version constants.  Raises
  97        KickstartVersionError if string does not match anything.
  98     """
  99     # First try these short forms.
 100     try:
 101         return versionMap[s.upper()]
 102     except KeyError:
 103         pass
 104
 105     # Now try the Fedora versions.
 106     m = re.match(r"^fedora.* (\d+)$", s, re.I)
 107
 108     if m and m.group(1):
 109         if "FC" + m.group(1) in versionMap:
 110             return versionMap["FC" + m.group(1)]
 111         elif "F" + m.group(1) in versionMap:
 112             return versionMap["F" + m.group(1)]
 113         else:
 114             raise KickstartVersionError(_("Unsupported version specified: %s") % s)
 115
 116     # Now try the RHEL versions.
 117     m = re.match(r"^red hat enterprise linux.* (\d+)([\.\d]*)$", s, re.I)
 118
 119     if m and m.group(1):
 120         if "RHEL" + m.group(1) in versionMap:
 121             return versionMap["RHEL" + m.group(1)]
 122         else:
 123             raise KickstartVersionError(_("Unsupported version specified: %s") % s)
 124
 125     # If nothing else worked, we're out of options.
 126     raise KickstartVersionError(_("Unsupported version specified: %s") % s)
 127
 128 def versionToString(version, skipDevel=False):
 129     """Convert version into a string representation of the version number.
 130        This is the reverse operation of stringToVersion.  Raises
 131        KickstartVersionError if version does not match anything.
 132     """
 133     if not skipDevel and version == versionMap["DEVEL"]:
 134         return "DEVEL"
 135
 136     for (key, val) in list(versionMap.items()):
 137         if key == "DEVEL":
 138             continue
 139         elif val == version:
 140             return key
 141
 142     raise KickstartVersionError(_("Unsupported version specified: %s") % version)
 143
 144 def versionFromFile(f):
 145     """Given a file or URL, look for a line starting with #version= and
 146        return the version number.  If no version is found, return DEVEL.
 147     """
 148     v = DEVEL
 149
 150     fh = urlopen(f)
 151
 152     while True:
 153         try:
 154             l = fh.readline()
 155         except StopIteration:
 156             break
 157
 158         # At the end of the file?
 159         if l == "":
 160             break
 161
 162         if l.isspace() or l.strip() == "":
 163             continue
 164
 165         if l[:9] == "#version=":
 166             v = stringToVersion(l[9:].rstrip())
 167             break
 168
 169     fh.close()
 170     return v
 171
 172 def returnClassForVersion(version=DEVEL):
 173     """Return the class of the syntax handler for version.  version can be
 174        either a string or the matching constant.  Raises KickstartValueError
 175        if version does not match anything.
 176     """
 177     try:
 178         version = int(version)
 179         module = "%s" % versionToString(version, skipDevel=True)
 180     except ValueError:
 181         module = "%s" % version
 182         version = stringToVersion(version)
 183
 184     module = module.lower()
 185
 186     try:
 187         import pykickstart.handlers
 188         sys.path.extend(pykickstart.handlers.__path__)
 189         found = imputil.imp.find_module(module)
 190         loaded = imputil.imp.load_module(module, found[0], found[1], found[2])
 191
 192         for (k, v) in list(loaded.__dict__.items()):
 193             if k.lower().endswith("%shandler" % module):
 194                 return v
 195     except:
 196         raise KickstartVersionError(_("Unsupported version specified: %s") % version)
 197
 198 def makeVersion(version=DEVEL):
 199     """Return a new instance of the syntax handler for version.  version can be
 200        either a string or the matching constant.  This function is useful for
 201        standalone programs which just need to handle a specific version of
 202        kickstart syntax (as provided by a command line argument, for example)
 203        and need to instantiate the correct object.
 204     """
 205     cl = returnClassForVersion(version)
 206     return cl()