openmedialibrary_platform/Linux_i686/lib/python2.7/site-packages/alembic/util.py
2014-05-17 18:11:40 +00:00

348 lines
10 KiB
Python

import sys
import os
import textwrap
import warnings
import re
import inspect
import uuid
from mako.template import Template
from sqlalchemy.engine import url
from sqlalchemy import __version__
from .compat import callable, exec_, load_module_py, load_module_pyc, binary_type
class CommandError(Exception):
pass
def _safe_int(value):
try:
return int(value)
except:
return value
_vers = tuple([_safe_int(x) for x in re.findall(r'(\d+|[abc]\d)', __version__)])
sqla_07 = _vers > (0, 7, 2)
sqla_08 = _vers >= (0, 8, 0, 'b2')
sqla_09 = _vers >= (0, 9, 0)
sqla_092 = _vers >= (0, 9, 2)
sqla_094 = _vers >= (0, 9, 4)
if not sqla_07:
raise CommandError(
"SQLAlchemy 0.7.3 or greater is required. ")
from sqlalchemy.util import format_argspec_plus, update_wrapper
from sqlalchemy.util.compat import inspect_getfullargspec
try:
import fcntl
import termios
import struct
ioctl = fcntl.ioctl(0, termios.TIOCGWINSZ,
struct.pack('HHHH', 0, 0, 0, 0))
_h, TERMWIDTH, _hp, _wp = struct.unpack('HHHH', ioctl)
if TERMWIDTH <= 0: # can occur if running in emacs pseudo-tty
TERMWIDTH = None
except (ImportError, IOError):
TERMWIDTH = None
def template_to_file(template_file, dest, **kw):
with open(dest, 'w') as f:
f.write(
Template(filename=template_file).render(**kw)
)
def create_module_class_proxy(cls, globals_, locals_):
"""Create module level proxy functions for the
methods on a given class.
The functions will have a compatible signature
as the methods. A proxy is established
using the ``_install_proxy(obj)`` function,
and removed using ``_remove_proxy()``, both
installed by calling this function.
"""
attr_names = set()
def _install_proxy(obj):
globals_['_proxy'] = obj
for name in attr_names:
globals_[name] = getattr(obj, name)
def _remove_proxy():
globals_['_proxy'] = None
for name in attr_names:
del globals_[name]
globals_['_install_proxy'] = _install_proxy
globals_['_remove_proxy'] = _remove_proxy
def _create_op_proxy(name):
fn = getattr(cls, name)
spec = inspect.getargspec(fn)
if spec[0] and spec[0][0] == 'self':
spec[0].pop(0)
args = inspect.formatargspec(*spec)
num_defaults = 0
if spec[3]:
num_defaults += len(spec[3])
name_args = spec[0]
if num_defaults:
defaulted_vals = name_args[0 - num_defaults:]
else:
defaulted_vals = ()
apply_kw = inspect.formatargspec(
name_args, spec[1], spec[2],
defaulted_vals,
formatvalue=lambda x: '=' + x)
def _name_error(name):
raise NameError(
"Can't invoke function '%s', as the proxy object has "\
"not yet been "
"established for the Alembic '%s' class. "
"Try placing this code inside a callable." % (
name, cls.__name__
))
globals_['_name_error'] = _name_error
func_text = textwrap.dedent("""\
def %(name)s(%(args)s):
%(doc)r
try:
p = _proxy
except NameError:
_name_error('%(name)s')
return _proxy.%(name)s(%(apply_kw)s)
e
""" % {
'name': name,
'args': args[1:-1],
'apply_kw': apply_kw[1:-1],
'doc': fn.__doc__,
})
lcl = {}
exec_(func_text, globals_, lcl)
return lcl[name]
for methname in dir(cls):
if not methname.startswith('_'):
if callable(getattr(cls, methname)):
locals_[methname] = _create_op_proxy(methname)
else:
attr_names.add(methname)
def write_outstream(stream, *text):
encoding = getattr(stream, 'encoding', 'ascii') or 'ascii'
for t in text:
if not isinstance(t, binary_type):
t = t.encode(encoding, 'replace')
t = t.decode(encoding)
try:
stream.write(t)
except IOError:
# suppress "broken pipe" errors.
# no known way to handle this on Python 3 however
# as the exception is "ignored" (noisily) in TextIOWrapper.
break
def coerce_resource_to_filename(fname):
"""Interpret a filename as either a filesystem location or as a package resource.
Names that are non absolute paths and contain a colon
are interpreted as resources and coerced to a file location.
"""
if not os.path.isabs(fname) and ":" in fname:
import pkg_resources
fname = pkg_resources.resource_filename(*fname.split(':'))
return fname
def status(_statmsg, fn, *arg, **kw):
msg(_statmsg + " ...", False)
try:
ret = fn(*arg, **kw)
write_outstream(sys.stdout, " done\n")
return ret
except:
write_outstream(sys.stdout, " FAILED\n")
raise
def err(message):
msg(message)
sys.exit(-1)
def obfuscate_url_pw(u):
u = url.make_url(u)
if u.password:
u.password = 'XXXXX'
return str(u)
def asbool(value):
return value is not None and \
value.lower() == 'true'
def warn(msg):
warnings.warn(msg)
def msg(msg, newline=True):
if TERMWIDTH is None:
write_outstream(sys.stdout, msg)
if newline:
write_outstream(sys.stdout, "\n")
else:
# left indent output lines
lines = textwrap.wrap(msg, TERMWIDTH)
if len(lines) > 1:
for line in lines[0:-1]:
write_outstream(sys.stdout, " ", line, "\n")
write_outstream(sys.stdout, " ", lines[-1], ("\n" if newline else ""))
def load_python_file(dir_, filename):
"""Load a file from the given path as a Python module."""
module_id = re.sub(r'\W', "_", filename)
path = os.path.join(dir_, filename)
_, ext = os.path.splitext(filename)
if ext == ".py":
if os.path.exists(path):
module = load_module_py(module_id, path)
elif os.path.exists(simple_pyc_file_from_path(path)):
# look for sourceless load
module = load_module_pyc(module_id, simple_pyc_file_from_path(path))
else:
raise ImportError("Can't find Python file %s" % path)
elif ext in (".pyc", ".pyo"):
module = load_module_pyc(module_id, path)
del sys.modules[module_id]
return module
def simple_pyc_file_from_path(path):
"""Given a python source path, return the so-called
"sourceless" .pyc or .pyo path.
This just a .pyc or .pyo file where the .py file would be.
Even with PEP-3147, which normally puts .pyc/.pyo files in __pycache__,
this use case remains supported as a so-called "sourceless module import".
"""
if sys.flags.optimize:
return path + "o" # e.g. .pyo
else:
return path + "c" # e.g. .pyc
def pyc_file_from_path(path):
"""Given a python source path, locate the .pyc.
See http://www.python.org/dev/peps/pep-3147/
#detecting-pep-3147-availability
http://www.python.org/dev/peps/pep-3147/#file-extension-checks
"""
import imp
has3147 = hasattr(imp, 'get_tag')
if has3147:
return imp.cache_from_source(path)
else:
return simple_pyc_file_from_path(path)
def rev_id():
val = int(uuid.uuid4()) % 100000000000000
return hex(val)[2:-1]
class memoized_property(object):
"""A read-only @property that is only evaluated once."""
def __init__(self, fget, doc=None):
self.fget = fget
self.__doc__ = doc or fget.__doc__
self.__name__ = fget.__name__
def __get__(self, obj, cls):
if obj is None:
return None
obj.__dict__[self.__name__] = result = self.fget(obj)
return result
class immutabledict(dict):
def _immutable(self, *arg, **kw):
raise TypeError("%s object is immutable" % self.__class__.__name__)
__delitem__ = __setitem__ = __setattr__ = \
clear = pop = popitem = setdefault = \
update = _immutable
def __new__(cls, *args):
new = dict.__new__(cls)
dict.__init__(new, *args)
return new
def __init__(self, *args):
pass
def __reduce__(self):
return immutabledict, (dict(self), )
def union(self, d):
if not self:
return immutabledict(d)
else:
d2 = immutabledict(self)
dict.update(d2, d)
return d2
def __repr__(self):
return "immutabledict(%s)" % dict.__repr__(self)
def _with_legacy_names(translations):
def decorate(fn):
spec = inspect_getfullargspec(fn)
metadata = dict(target='target', fn='fn')
metadata.update(format_argspec_plus(spec, grouped=False))
has_keywords = bool(spec[2])
if not has_keywords:
metadata['args'] += ", **kw"
metadata['apply_kw'] += ", **kw"
def go(*arg, **kw):
names = set(kw).difference(spec[0])
for oldname, newname in translations:
if oldname in kw:
kw[newname] = kw.pop(oldname)
names.discard(oldname)
warnings.warn(
"Argument '%s' is now named '%s' for function '%s'" %
(oldname, newname, fn.__name__))
if not has_keywords and names:
raise TypeError("Unknown arguments: %s" % ", ".join(names))
return fn(*arg, **kw)
code = 'lambda %(args)s: %(target)s(%(apply_kw)s)' % (
metadata)
decorated = eval(code, {"target": go})
decorated.__defaults__ = getattr(fn, '__func__', fn).__defaults__
update_wrapper(decorated, fn)
if hasattr(decorated, '__wrapped__'):
# update_wrapper in py3k applies __wrapped__, which causes
# inspect.getargspec() to ignore the extra arguments on our
# wrapper as of Python 3.4. We need this for the
# "module class proxy" thing though, so just del the __wrapped__
# for now. See #175 as well as bugs.python.org/issue17482
del decorated.__wrapped__
return decorated
return decorate