wxWidgets/wxPython/wxversion/wxversion.py
2004-10-24 00:58:11 +00:00

321 lines
10 KiB
Python

#----------------------------------------------------------------------
# Name: wxversion
# Purpose: Allows a wxPython program to search for alternate
# installations of the wxPython packages and modify sys.path
# so they will be found when "import wx" is done.
#
# Author: Robin Dunn
#
# Created: 24-Sept-2004
# RCS-ID: $Id$
# Copyright: (c) 2004 by Total Control Software
# Licence: wxWindows license
#----------------------------------------------------------------------
"""
If you have more than one version of wxPython installed this module
allows your application to choose which version of wxPython will be
imported when it does 'import wx'. You use it like this::
import wxversion
wxversion.select('2.4')
import wx
Or additional build options can also be selected, like this::
import wxversion
wxversion.select('2.5.3-unicode')
import wx
Of course the default wxPython version can also be controlled by
setting PYTHONPATH or by editing the wx.pth path configuration file,
but using wxversion will allow an application to manage the version
selection itself rather than depend on the user to setup the
environment correctly.
It works by searching the sys.path for directories matching wx-* and
then comparing them to what was passed to the require function. If a
match is found then that path is inserted into sys.path.
NOTE: If you are making a 'bundle' of your application with a tool
like py2exe then you should *not* use the wxversion module since it
looks at filesystem for the directories on sys.path, it will fail in a
bundled environment. Instead you should simply ensure that the
version of wxPython that you want is found by default on the sys.path
when making the bundled version by setting PYTHONPATH. Then that
version will be included in your bundle and your app will work as
expected. Py2exe and the others usually have a way to tell at runtime
if they are running from a bundle or running raw, so you can check
that and only use wxversion if needed. For example, for py2exe::
if not hasattr(sys, 'frozen'):
import wxversion
wxversion.select('2.5')
import wx
"""
import sys, os, glob, fnmatch
_selected = None
class VersionError(Exception):
pass
#----------------------------------------------------------------------
def select(versions):
"""
Search for a wxPython installation that matches version. If one
is found then sys.path is modified so that version will be
imported with a 'import wx', otherwise a VersionError exception is
raised. This funciton should only be caled once at the begining
of the application before wxPython is imported.
:param version: Specifies the version to look for, it can
either be a string or a list of strings. Each
string is compared to the installed wxPythons
and the best match is inserted into the
sys.path, allowing an 'import wx' to find that
version.
The version string is composed of the dotted
version number (at least 2 of the 4 components)
optionally followed by hyphen ('-') separated
options (wx port, unicode/ansi, flavour, etc.) A
match is determined by how much of the installed
version matches what is given in the version
parameter. If the version number components don't
match then the score is zero, otherwise the score
is increased for every specified optional component
that is specified and that matches.
"""
if type(versions) == str:
versions = [versions]
global _selected
if _selected is not None:
# A version was previously selected, ensure that it matches
# this new request
for ver in versions:
if _selected.Score(_wxPackageInfo(ver)) > 0:
return
# otherwise, raise an exception
raise VersionError("A previously selected wx version does not match the new request.")
# If we get here then this is the first time wxversion is used.
# Ensure that wxPython hasn't been imported yet.
if sys.modules.has_key('wx') or sys.modules.has_key('wxPython'):
raise VersionError("wxversion.require() must be called before wxPython is imported")
# Look for a matching version and manipulate the sys.path as
# needed to allow it to be imported.
packages = _find_installed(True)
bestMatch = _get_best_match(packages, versions)
if bestMatch is None:
raise VersionError("Requested version of wxPython not found")
sys.path.insert(0, bestMatch.pathname)
_selected = bestMatch
#----------------------------------------------------------------------
def checkInstalled(versions):
"""
Check if there is a version of wxPython installed that matches one
of the versions given. Returns True if so, False if not. This
can be used to determine if calling `select` will succeed or not.
:param version: Same as in `select`, either a string or a list
of strings specifying the version(s) to check
for.
"""
if type(versions) == str:
versions = [versions]
packages = _find_installed()
bestMatch = _get_best_match(packages, versions)
return bestMatch is not None
#----------------------------------------------------------------------
def getInstalled():
"""
Returns a list of strings representing the installed wxPython
versions that are found on the system.
"""
packages = _find_installed()
return [os.path.basename(p.pathname)[3:] for p in packages]
#----------------------------------------------------------------------
# private helpers...
def _get_best_match(packages, versions):
bestMatch = None
bestScore = 0
for pkg in packages:
for ver in versions:
score = pkg.Score(_wxPackageInfo(ver))
if score > bestScore:
bestMatch = pkg
bestScore = score
return bestMatch
_pattern = "wx-[0-9].*"
def _find_installed(removeExisting=False):
installed = []
toRemove = []
for pth in sys.path:
# empty means to look in the current dir
if not pth:
pth = '.'
# skip it if it's not a package dir
if not os.path.isdir(pth):
continue
base = os.path.basename(pth)
# if it's a wx path that's already in the sys.path then mark
# it for removal and then skip it
if fnmatch.fnmatchcase(base, _pattern):
toRemove.append(pth)
continue
# now look in the dir for matching subdirs
for name in glob.glob(os.path.join(pth, _pattern)):
# make sure it's a directory
if not os.path.isdir(name):
continue
# and has a wx subdir
if not os.path.exists(os.path.join(name, 'wx')):
continue
installed.append(_wxPackageInfo(name, True))
if removeExisting:
for rem in toRemove:
del sys.path[sys.path.index(rem)]
installed.sort()
installed.reverse()
return installed
class _wxPackageInfo(object):
def __init__(self, pathname, stripFirst=False):
self.pathname = pathname
base = os.path.basename(pathname)
segments = base.split('-')
if stripFirst:
segments = segments[1:]
self.version = tuple([int(x) for x in segments[0].split('.')])
self.options = segments[1:]
def Score(self, other):
score = 0
# whatever version components given in other must match exactly
minlen = min(len(self.version), len(other.version))
if self.version[:minlen] != other.version[:minlen]:
return 0
score += 1 # todo: should it be +=minlen to reward longer matches?
for opt in other.options:
if opt in self.options:
score += 1
return score
# TODO: factor self.options into the sort order?
def __lt__(self, other):
return self.version < other.version
def __gt__(self, other):
return self.version > other.version
def __eq__(self, other):
return self.version == other.version
#----------------------------------------------------------------------
if __name__ == '__main__':
import pprint
def test(version):
# setup
savepath = sys.path[:]
#test
select(version)
print "Asked for %s:\t got: %s" % (version, sys.path[0])
#pprint.pprint(sys.path)
#print
# reset
sys.path = savepath[:]
global _selected
_selected = None
# make some test dirs
names = ['wx-2.4',
'wx-2.5.2',
'wx-2.5.2.9-gtk2-unicode',
'wx-2.5.2.9-gtk-ansi',
'wx-2.5.1',
'wx-2.5.2.8-gtk2-unicode',
'wx-2.5.3']
for name in names:
d = os.path.join('/tmp', name)
os.mkdir(d)
os.mkdir(os.path.join(d, 'wx'))
# setup sys.path to see those dirs
sys.path.append('/tmp')
# now run some tests
pprint.pprint( getInstalled())
print checkInstalled("2.4")
print checkInstalled("2.5-unicode")
print checkInstalled("2.99-bogus")
test("2.4")
test("2.5")
test("2.5-gtk2")
test("2.5.2")
test("2.5-ansi")
test("2.5-unicode")
# There isn't a unicode match for this one, but it will give the best
# available 2.4. Should it give an error instead? I don't think so...
test("2.4-unicode")
# Try asking for multiple versions
test(["2.6", "2.5.3", "2.5.2-gtk2"])
try:
# expecting an error on this one
test("2.6")
except VersionError, e:
print "Asked for 2.6:\t got Exception:", e
# check for exception when incompatible versions are requested
try:
select("2.4")
select("2.5")
except VersionError, e:
print "Asked for incompatible versions, got Exception:", e
# cleanup
for name in names:
d = os.path.join('/tmp', name)
os.rmdir(os.path.join(d, 'wx'))
os.rmdir(d)