# copyright 2003-2010 LOGILAB S.A. (Paris, FRANCE), all rights reserved.
# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr
#
# This file is part of CubicWeb.
#
# CubicWeb is free software: you can redistribute it and/or modify it under the
# terms of the GNU Lesser General Public License as published by the Free
# Software Foundation, either version 2.1 of the License, or (at your option)
# any later version.
#
# CubicWeb is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
# details.
#
# You should have received a copy of the GNU Lesser General Public License along
# with CubicWeb. If not, see <http://www.gnu.org/licenses/>.
"""utilities for instances migration
"""
__docformat__ = "restructuredtext en"
import sys
import os
import logging
import tempfile
from os.path import exists, join, basename, splitext
from logilab.common.decorators import cached
from logilab.common.configuration import REQUIRED, read_old_config
from logilab.common.shellutils import ASK
from logilab.common.changelog import Version
from cubicweb import ConfigurationError
def filter_scripts(config, directory, fromversion, toversion, quiet=True):
"""return a list of paths of migration files to consider to upgrade
from a version to a greater one
"""
from logilab.common.changelog import Version # doesn't work with appengine
assert fromversion
assert toversion
assert isinstance(fromversion, tuple), fromversion.__class__
assert isinstance(toversion, tuple), toversion.__class__
assert fromversion <= toversion, (fromversion, toversion)
if not exists(directory):
if not quiet:
print directory, "doesn't exists, no migration path"
return []
if fromversion == toversion:
return []
result = []
for fname in os.listdir(directory):
if fname.endswith('.pyc') or fname.endswith('.pyo') \
or fname.endswith('~'):
continue
fpath = join(directory, fname)
try:
tver, mode = fname.split('_', 1)
except ValueError:
continue
mode = mode.split('.', 1)[0]
if not config.accept_mode(mode):
continue
try:
tver = Version(tver)
except ValueError:
continue
if tver <= fromversion:
continue
if tver > toversion:
continue
result.append((tver, fpath))
# be sure scripts are executed in order
return sorted(result)
IGNORED_EXTENSIONS = ('.swp', '~')
def execscript_confirm(scriptpath):
"""asks for confirmation before executing a script and provides the
ability to show the script's content
"""
while True:
answer = ASK.ask('Execute %r ?' % scriptpath,
('Y','n','show','abort'), 'Y')
if answer == 'abort':
raise SystemExit(1)
elif answer == 'n':
return False
elif answer == 'show':
stream = open(scriptpath)
scriptcontent = stream.read()
stream.close()
print
print scriptcontent
print
else:
return True
def yes(*args, **kwargs):
return True
class MigrationHelper(object):
"""class holding CubicWeb Migration Actions used by migration scripts"""
def __init__(self, config, interactive=True, verbosity=1):
self.config = config
if config:
# no config on shell to a remote instance
self.config.init_log(logthreshold=logging.ERROR, debug=True)
# 0: no confirmation, 1: only main commands confirmed, 2 ask for everything
self.verbosity = verbosity
self.need_wrap = True
if not interactive or not verbosity:
self.confirm = yes
self.execscript_confirm = yes
else:
self.execscript_confirm = execscript_confirm
self._option_changes = []
self.__context = {'confirm': self.confirm,
'config': self.config,
'interactive_mode': interactive,
}
def __getattribute__(self, name):
try:
return object.__getattribute__(self, name)
except AttributeError:
cmd = 'cmd_%s' % name
if hasattr(self, cmd):
meth = getattr(self, cmd)
return lambda *args, **kwargs: self.interact(args, kwargs,
meth=meth)
raise
raise AttributeError(name)
def repo_connect(self):
return self.config.repository()
def migrate(self, vcconf, toupgrade, options):
"""upgrade the given set of cubes
`cubes` is an ordered list of 3-uple:
(cube, fromversion, toversion)
"""
if options.fs_only:
# monkey path configuration.accept_mode so database mode (e.g. Any)
# won't be accepted
orig_accept_mode = self.config.accept_mode
def accept_mode(mode):
if mode == 'Any':
return False
return orig_accept_mode(mode)
self.config.accept_mode = accept_mode
# may be an iterator
toupgrade = tuple(toupgrade)
vmap = dict( (cube, (fromver, tover)) for cube, fromver, tover in toupgrade)
ctx = self.__context
ctx['versions_map'] = vmap
if self.config.accept_mode('Any') and 'cubicweb' in vmap:
migrdir = self.config.migration_scripts_dir()
self.cmd_process_script(join(migrdir, 'bootstrapmigration_repository.py'))
for cube, fromversion, toversion in toupgrade:
if cube == 'cubicweb':
migrdir = self.config.migration_scripts_dir()
else:
migrdir = self.config.cube_migration_scripts_dir(cube)
scripts = filter_scripts(self.config, migrdir, fromversion, toversion)
if scripts:
prevversion = None
for version, script in scripts:
# take care to X.Y.Z_Any.py / X.Y.Z_common.py: we've to call
# cube_upgraded once all script of X.Y.Z have been executed
if prevversion is not None and version != prevversion:
self.cube_upgraded(cube, prevversion)
prevversion = version
self.cmd_process_script(script)
self.cube_upgraded(cube, toversion)
else:
self.cube_upgraded(cube, toversion)
def cube_upgraded(self, cube, version):
pass
def shutdown(self):
pass
def interact(self, args, kwargs, meth):
"""execute the given method according to user's confirmation"""
msg = 'Execute command: %s(%s) ?' % (
meth.__name__[4:],
', '.join([repr(arg) for arg in args] +
['%s=%r' % (n,v) for n,v in kwargs.items()]))
if 'ask_confirm' in kwargs:
ask_confirm = kwargs.pop('ask_confirm')
else:
ask_confirm = True
if not ask_confirm or self.confirm(msg):
return meth(*args, **kwargs)
def confirm(self, question, shell=True, abort=True, retry=False, default='y'):
"""ask for confirmation and return true on positive answer
if `retry` is true the r[etry] answer may return 2
"""
possibleanswers = ['y', 'n']
if abort:
possibleanswers.append('abort')
if shell:
possibleanswers.append('shell')
if retry:
possibleanswers.append('retry')
try:
answer = ASK.ask(question, possibleanswers, default)
except (EOFError, KeyboardInterrupt):
answer = 'abort'
if answer == 'n':
return False
if answer == 'retry':
return 2
if answer == 'abort':
raise SystemExit(1)
if shell and answer == 'shell':
self.interactive_shell()
return self.confirm(question)
return True
def interactive_shell(self):
self.confirm = yes
self.need_wrap = False
# avoid '_' to be added to builtins by sys.display_hook
def do_not_add___to_builtins(obj):
if obj is not None:
print repr(obj)
sys.displayhook = do_not_add___to_builtins
local_ctx = self._create_context()
try:
import readline
from rlcompleter import Completer
except ImportError:
# readline not available
pass
else:
readline.set_completer(Completer(local_ctx).complete)
readline.parse_and_bind('tab: complete')
home_key = 'HOME'
if sys.platform == 'win32':
home_key = 'USERPROFILE'
histfile = os.path.join(os.environ[home_key], ".eshellhist")
try:
readline.read_history_file(histfile)
except IOError:
pass
from code import interact
banner = """entering the migration python shell
just type migration commands or arbitrary python code and type ENTER to execute it
type "exit" or Ctrl-D to quit the shell and resume operation"""
# give custom readfunc to avoid http://bugs.python.org/issue1288615
def unicode_raw_input(prompt):
return unicode(raw_input(prompt), sys.stdin.encoding)
interact(banner, readfunc=unicode_raw_input, local=local_ctx)
readline.write_history_file(histfile)
# delete instance's confirm attribute to avoid questions
del self.confirm
self.need_wrap = True
@cached
def _create_context(self):
"""return a dictionary to use as migration script execution context"""
context = self.__context
for attr in dir(self):
if attr.startswith('cmd_'):
if self.need_wrap:
context[attr[4:]] = getattr(self, attr[4:])
else:
context[attr[4:]] = getattr(self, attr)
return context
def cmd_process_script(self, migrscript, funcname=None, *args, **kwargs):
"""execute a migration script
in interactive mode, display the migration script path, ask for
confirmation and execute it if confirmed
"""
migrscript = os.path.normpath(migrscript)
if migrscript.endswith('.py'):
script_mode = 'python'
elif migrscript.endswith('.txt') or migrscript.endswith('.rst'):
script_mode = 'doctest'
else:
raise Exception('This is not a valid cubicweb shell input')
if not self.execscript_confirm(migrscript):
return
scriptlocals = self._create_context().copy()
if script_mode == 'python':
if funcname is None:
pyname = '__main__'
else:
pyname = splitext(basename(migrscript))[0]
scriptlocals.update({'__file__': migrscript, '__name__': pyname})
execfile(migrscript, scriptlocals)
if funcname is not None:
try:
func = scriptlocals[funcname]
self.info('found %s in locals', funcname)
assert callable(func), '%s (%s) is not callable' % (func, funcname)
except KeyError:
self.critical('no %s in script %s', funcname, migrscript)
return None
return func(*args, **kwargs)
else: # script_mode == 'doctest'
import doctest
doctest.testfile(migrscript, module_relative=False,
optionflags=doctest.ELLIPSIS, globs=scriptlocals)
def cmd_option_renamed(self, oldname, newname):
"""a configuration option has been renamed"""
self._option_changes.append(('renamed', oldname, newname))
def cmd_option_group_changed(self, option, oldgroup, newgroup):
"""a configuration option has been moved in another group"""
self._option_changes.append(('moved', option, oldgroup, newgroup))
def cmd_option_added(self, optname):
"""a configuration option has been added"""
self._option_changes.append(('added', optname))
def cmd_option_removed(self, optname):
"""a configuration option has been removed"""
# can safely be ignored
#self._option_changes.append(('removed', optname))
def cmd_option_type_changed(self, optname, oldtype, newvalue):
"""a configuration option's type has changed"""
self._option_changes.append(('typechanged', optname, oldtype, newvalue))
def cmd_add_cubes(self, cubes):
"""modify the list of used cubes in the in-memory config
returns newly inserted cubes, including dependencies
"""
if isinstance(cubes, basestring):
cubes = (cubes,)
origcubes = self.config.cubes()
newcubes = [p for p in self.config.expand_cubes(cubes)
if not p in origcubes]
if newcubes:
for cube in cubes:
assert cube in newcubes
self.config.add_cubes(newcubes)
return newcubes
def cmd_remove_cube(self, cube, removedeps=False):
if removedeps:
toremove = self.config.expand_cubes([cube])
else:
toremove = (cube,)
origcubes = self.config._cubes
basecubes = [c for c in origcubes if not c in toremove]
self.config._cubes = tuple(self.config.expand_cubes(basecubes))
removed = [p for p in origcubes if not p in self.config._cubes]
if not cube in removed:
raise ConfigurationError("can't remove cube %s, "
"used as a dependency" % cube)
return removed
def rewrite_configuration(self):
# import locally, show_diffs unavailable in gae environment
from cubicweb.toolsutils import show_diffs
configfile = self.config.main_config_file()
if self._option_changes:
read_old_config(self.config, self._option_changes, configfile)
fd, newconfig = tempfile.mkstemp()
for optdescr in self._option_changes:
if optdescr[0] == 'added':
optdict = self.config.get_option_def(optdescr[1])
if optdict.get('default') is REQUIRED:
self.config.input_option(optdescr[1], optdict)
self.config.generate_config(open(newconfig, 'w'))
show_diffs(configfile, newconfig, askconfirm=self.confirm is not yes)
os.close(fd)
if exists(newconfig):
os.unlink(newconfig)
from logging import getLogger
from cubicweb import set_log_methods
set_log_methods(MigrationHelper, getLogger('cubicweb.migration'))
def version_strictly_lower(a, b):
if a:
a = Version(a)
if b:
b = Version(b)
return a < b
def max_version(a, b):
return str(max(Version(a), Version(b)))
class ConfigurationProblem(object):
"""Each cube has its own list of dependencies on other cubes/versions.
The ConfigurationProblem is used to record the loaded cubes, then to detect
inconsistencies in their dependencies.
See configuration management on wikipedia for litterature.
"""
def __init__(self, config):
self.cubes = {}
self.config = config
def add_cube(self, name, version):
self.cubes[name] = version
def solve(self):
self.warnings = []
self.errors = []
self.read_constraints()
for cube, versions in sorted(self.constraints.items()):
oper, version = None, None
# simplify constraints
if versions:
for constraint in versions:
op, ver = constraint
if oper is None:
oper = op
version = ver
elif op == '>=' and oper == '>=':
version = max_version(ver, version)
else:
print 'unable to handle this case', oper, version, op, ver
# "solve" constraint satisfaction problem
if cube not in self.cubes:
self.errors.append( ('add', cube, version) )
elif versions:
lower_strict = version_strictly_lower(self.cubes[cube], version)
if oper in ('>=','='):
if lower_strict:
self.errors.append( ('update', cube, version) )
else:
print 'unknown operator', oper
def read_constraints(self):
self.constraints = {}
self.reverse_constraints = {}
for cube in self.cubes:
use = self.config.cube_dependencies(cube)
for name, constraint in use.iteritems():
self.constraints.setdefault(name,set())
if constraint:
try:
oper, version = constraint.split()
self.constraints[name].add( (oper, version) )
except:
self.warnings.append(
'cube %s depends on %s but constraint badly '
'formatted: %s' % (cube, name, constraint))
self.reverse_constraints.setdefault(name, set()).add(cube)