test_ok1/py/impl/_com.py

126 lines
3.8 KiB
Python

"""
py lib plugins and plugin call management
"""
import py
import inspect
__all__ = ['Registry', 'MultiCall', 'comregistry', 'HookRelay']
class MultiCall:
""" execute a call into multiple python functions/methods. """
def __init__(self, methods, kwargs, firstresult=False):
self.methods = methods[:]
self.kwargs = kwargs.copy()
self.kwargs['__multicall__'] = self
self.results = []
self.firstresult = firstresult
def __repr__(self):
status = "%d results, %d meths" % (len(self.results), len(self.methods))
return "<MultiCall %s, kwargs=%r>" %(status, self.kwargs)
def execute(self):
while self.methods:
method = self.methods.pop()
kwargs = self.getkwargs(method)
res = method(**kwargs)
if res is not None:
self.results.append(res)
if self.firstresult:
return res
if not self.firstresult:
return self.results
def getkwargs(self, method):
kwargs = {}
for argname in varnames(method):
try:
kwargs[argname] = self.kwargs[argname]
except KeyError:
pass # might be optional param
return kwargs
def varnames(func):
ismethod = inspect.ismethod(func)
rawcode = py.code.getrawcode(func)
try:
return rawcode.co_varnames[ismethod:]
except AttributeError:
return ()
class Registry:
"""
Manage Plugins: register/unregister call calls to plugins.
"""
def __init__(self, plugins=None):
if plugins is None:
plugins = []
self._plugins = plugins
def register(self, plugin):
assert not isinstance(plugin, str)
assert not plugin in self._plugins
self._plugins.append(plugin)
def unregister(self, plugin):
self._plugins.remove(plugin)
def isregistered(self, plugin):
return plugin in self._plugins
def __iter__(self):
return iter(self._plugins)
def listattr(self, attrname, plugins=None, extra=(), reverse=False):
l = []
if plugins is None:
plugins = self._plugins
candidates = list(plugins) + list(extra)
for plugin in candidates:
try:
l.append(getattr(plugin, attrname))
except AttributeError:
continue
if reverse:
l.reverse()
return l
class HookRelay:
def __init__(self, hookspecs, registry):
self._hookspecs = hookspecs
self._registry = registry
for name, method in vars(hookspecs).items():
if name[:1] != "_":
setattr(self, name, self._makecall(name))
def _makecall(self, name, extralookup=None):
hookspecmethod = getattr(self._hookspecs, name)
firstresult = getattr(hookspecmethod, 'firstresult', False)
return HookCaller(self, name, firstresult=firstresult,
extralookup=extralookup)
def _getmethods(self, name, extralookup=()):
return self._registry.listattr(name, extra=extralookup)
def _performcall(self, name, multicall):
return multicall.execute()
class HookCaller:
def __init__(self, hookrelay, name, firstresult, extralookup=None):
self.hookrelay = hookrelay
self.name = name
self.firstresult = firstresult
self.extralookup = extralookup and [extralookup] or ()
def __repr__(self):
return "<HookCaller %r>" %(self.name,)
def __call__(self, **kwargs):
methods = self.hookrelay._getmethods(self.name, self.extralookup)
mc = MultiCall(methods, kwargs, firstresult=self.firstresult)
return self.hookrelay._performcall(self.name, mc)
comregistry = Registry([])