import re
import sys
import types
class GlueError(Exception):
pass
class RecursionError(GlueError):
pass
class NoSuchAttributeError(GlueError):
pass
def ispackage(m):
""" Determine if a module is a package - that means, sub-modules can be imported
Currently uses that it has a file name that matches '.*__init__.py[co]?$'
xxx is this portable/future-safe?
"""
try:
name = m.__file__
except AttributeError:
return 0
return re.match('.*__init__.py[co]?$', name)
def dotname(first, last):
if first and last:
return '%s.%s' % (first, last)
else:
return first + last
class Interface(object):
def __init__(self, share, owner, name):
self.__dict__['_share'] = share
self.__dict__['_owner'] = owner
self.__dict__['_name'] = name
for name in share.preload:
getattr(self, name)
def _import(self, *names):
return ','.join(names) + '=' + ','.join(['self._root.%s' % name for name in names])
def __getattr__(self, name):
return self._share.getattr(self, name)
def __setattr__(self, name, value):
return self._share.setattr(self, name, value)
class Owner:
def __init__(self, name):
self.name = name
self.galog = {}
self.salog = {}
self.inters = {}
def log_getattr(self, cache, name):
name = dotname(cache['_name'], name)
self.galog[name] = 1
def log_setattr(self, name):
self.salog[name] = 1
def makeInterface(self, cache, share, name):
name = dotname(cache['_name'], name)
if share not in self.inters:
Clamp = share.Clamp
if Clamp is not None and issubclass(Clamp, Interface):
NewInterface = Clamp
else:
NewInterface = Interface
self.inters[share] = NewInterface(share, self, name)
return self.inters[share]
def pp(self, out=None, short=0):
if out is None:
out = sys.stdout
if not short:
print('Attributes used by %s:' % self.name, file=out)
print(self.name[:self.name.rindex('.')+1], file=out)
complete = []
for a in self.galog:
for b in self.galog:
if a != b and b.startswith(a):
break
else:
complete.append(a)
complete.sort()
for a in complete:
print(' ', a)
class Share:
__slots__ = ('module', 'parent', 'name', 'Clamp', 'setable', 'chgable',
'importedfrom', 'nowrap', 'wrapattr', 'wrapping', 'data',
'owners', 'ispackage', 'recursion', 'preload')
has_getattr_logging_enabled = False
def __init__(self, module, parent, name, Clamp):
if parent is None:
parent = self
root = self
else:
root = parent.data['_root']
self.module = module
self.parent = parent
self.name = name
self.Clamp = Clamp
self.setable = getattr(Clamp, '_setable_', ())
if not isinstance(self.setable, tuple):
raise TypeError(self.message(
'the _setable_ attribute must be a tuple'))
self.chgable = getattr(Clamp, '_chgable_', ())
if not isinstance(self.chgable, tuple):
raise TypeError(self.message(
'the _chgable_ attribute must be a tuple'))
if Clamp is not None:
for attr in Clamp.__dict__:
if attr.startswith('_set_'):
attr = attr[len('_set_'):]
if attr not in self.setable and attr not in self.chgable:
raise TypeError(self.message(
'%s must be in either _setable_ or _chgable_ '
'for _set_%s to work' % (attr, attr)))
imports = getattr(Clamp, '_imports_', ())
if not isinstance(imports, tuple):
raise TypeError(self.message(
'the _imports_ attribute must be a tuple'))
self.importedfrom = {}
pres = {}
parent_inter = root_inter = None
for fi in imports:
presuf = fi.split(':')
if len(presuf) != 2:
if len(presuf) > 2:
s = "Too many"
else:
s = "No"
raise SyntaxError("%s ':' in import directive %r." % (s, fi))
pre, suf = presuf
pre = pre.strip()
prepa = pres.get(pre)
if prepa is None:
hdta = pre.split('.', 1)
hd = hdta[0]
if hd == '_parent':
if parent_inter is None:
parent_inter = Owner('').makeInterface(
{'_name': ''}, parent, '')
hdo = parent_inter
elif hd == '_root':
if root_inter is None:
root_inter = Owner('').makeInterface(
{'_name': ''}, root, '')
hdo = root_inter
else:
raise SyntaxError(
"Module must begin with _parent or _root")
if len(hdta) == 2:
prepa = [hdo, hdta[1], None]
else:
prepa = [hdo, '', hdo]
pres[pre] = prepa
sufs = suf.split(',')
for su in sufs:
su = su.strip()
im = getattr(Clamp, '_get_%s' % su, None)
if im is not None:
raise ValueError(
'Cant have both name (=%r) in boht importfrom and _get' % su)
self.importedfrom[su] = prepa
self.nowrap = getattr(Clamp, '_nowrap_', ())
if not isinstance(self.nowrap, tuple):
raise TypeError(self.message(
'the _nowrap_ attribute must be a tuple'))
wrapattr = getattr(Clamp, '_wrapattr_', None)
if not isinstance(wrapattr, types.FunctionType) and wrapattr is not None:
raise TypeError(self.message(
'the _wrapattr_ attribute must be a method'))
self.wrapattr = wrapattr
self.wrapping = 0
self.data = {}
self.owners = {}
self.ispackage = module is None or ispackage(module)
self.data['_parent'] = parent
self.data['_root'] = root
self.data['_module'] = module
self.recursion = 0
preload = getattr(Clamp, '_preload_', ())
if preload:
self.preload = ()
inter = Owner('').makeInterface({'_name': ''}, self, '')
for name in preload:
getattr(inter, name)
for name in preload:
assert name in self.data
self.preload = preload
def message(self, msg):
return '%s: in %r: %s' % (self.__class__, self.name, msg)
def getattr(self, inter, name):
owner = inter._owner
cache = inter.__dict__
d = self.getattr2(inter, cache, owner, name)
if name not in self.chgable:
cache[name] = d
return d
def getattr2(self, inter, cache, owner, name):
if self.has_getattr_logging_enabled:
owner.log_getattr(cache, name)
if name not in self.data:
try:
self.recursion += 1
try:
if self.ispackage:
try:
x = self.getattr3(inter, name)
except NoSuchAttributeError:
x = self.getattr_package(inter, name)
else:
x = self.getattr3(inter, name)
except NoSuchAttributeError:
if name == '__repr__':
return lambda: str(inter)
elif name == '__str__':
return lambda: '<%s interface at %s>' % (inter._name,
hex(id(self)))
else:
x = self.getattr_module(inter, name)
wrapattr = self.wrapattr
if wrapattr is not None and name not in self.nowrap:
assert not self.wrapping
try:
self.wrapping = 1
x = wrapattr(inter, x, name)
finally:
self.wrapping = 0
self.data[name] = x
finally:
self.recursion -= 1
x = self.data[name]
if isinstance(x, Share):
x = owner.makeInterface(cache, x, name)
return x
def getattr_module(self, inter, name):
try:
return getattr(self.module, name)
except AttributeError:
raise AttributeError('Module %r or its _GLUECLAMP_ has no attribute %r' % (
self.module.__name__, name))
def getattr_package(self, inter, name):
try:
x = __import__(self.makeName(name))
except ImportError as exc:
if (exc.args[0] != 'No module named \'%s\'' % self.makeName(name) or
(not self.module and name not in ('__repr__', '__str__'))):
raise
x = self.getattr3(inter, name)
# raise AttributeError, name
else:
if self.module:
x = self.getattr_module(inter, name)
if isinstance(x, types.ModuleType):
x = self.makeModule(x, name)
return x
def getattr3(self, inter, name):
if self.recursion >= 10:
raise RecursionError(name)
Clamp = self.Clamp
if Clamp is None:
raise NoSuchAttributeError(name)
try:
x = getattr(Clamp, name)
except AttributeError:
pass
else:
if isinstance(x, types.FunctionType):
x = types.MethodType(x, inter)
return x
try:
im = getattr(Clamp, '_get_%s' % name)
except AttributeError:
pass
else:
owner = self.makeOwner(name)
inter = Interface(self, owner, '')
f = types.MethodType(im, inter)
x = f()
if isinstance(x, Interface):
x = x.__dict__['_share']
return x
if name in self.importedfrom:
prepa = self.importedfrom[name]
hdo, ta, pa = prepa
if pa is None:
pa = hdo
tas = ta.split('.')
for at in tas:
pa = getattr(pa, at)
prepa[2] = pa
x = getattr(pa, name)
return x
gp = getattr(Clamp, '_GLUEPATH_', None)
if gp is None:
raise NoSuchAttributeError(name)
if hasattr(gp, 'split'):
gp = gp.split(',')
for a in gp:
a = a.strip()
bs = a.split('.')
ii = inter
for b in bs:
b = b.strip()
ii = getattr(ii, b)
try:
x = getattr(ii, name)
except AttributeError:
continue
else:
return x
raise NoSuchAttributeError(name)
def makeModule(self, module, name):
Clamp = getattr(module, '_GLUECLAMP_', None)
return Share(module, self, module.__name__, Clamp)
def makeName(self, name):
if self.name:
name = '%s.%s' % (self.name, name)
return name
def makeOwner(self, name):
owner_name = self.makeName(name)
owner = Owner(owner_name)
self.owners[owner_name] = owner
return owner
def pp(self, out=sys.stdout):
if not self.owners:
return
print('Dependencies found for %s' % self.name, file=out)
print('-----------------------'+'-'*len(self.name), file=out)
keys = list(self.owners.keys())
keys.sort()
for key in keys:
lastname = key[key.rindex('.')+1:]
print(lastname, file=out)
self.owners[key].pp(short=1)
print(file=out)
def rpp(self, out=sys.stdout):
self.pp(out)
for k, d in list(self.data.items()):
if k not in ('_root', '_parent'):
if isinstance(d, Share):
d.rpp()
def setattr(self, inter, name, value):
Clamp = self.Clamp
if Clamp is None:
raise ValueError(
'Can not change attribute %r because no _GLUECLAMP_ defined.' % name)
setable = self.setable
chgable = self.chgable
if (name not in setable and name not in chgable and
(not (name in self.data and self.data[name] is value))):
raise ValueError("""Can not change attribute %r,
because it is not in _setable_ or _chgable_.""" % name)
if name in self.data and self.data[name] is not value and name not in chgable:
raise ValueError("""Can not change attribute %r,
because it is already set and not in _chgable_.""" % name)
im = getattr(Clamp, '_set_%s' % name, None)
if im is not None:
im(inter, value)
self.data[name] = value
if name not in chgable: # This is a pain, I suppose. Should we track interfaces?
inter.__dict__[name] = value
class Test:
def __init__(self, root):
self.root = root
class _GLUECLAMP_:
pass
def Root():
"""\
Create a new guppy Root object.
All functionality in the system may be accessed from this object.
Modules are imported on demand when accessed. Other objects may be
created or imported on demand using Guppy Glue+ directives.
"""
share = Share(None, None, '', None)
r = Owner('').makeInterface({'_name': ''}, share, '')
return r
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